Civil Engineering Objective Type Questions PDF

DOWNLOADED FROM www.CivilEnggForAll.com DOWNLOADED FROM www.CivilEnggForAll.com Civil Engineering Objective Type Questions S.S. Bhavikatti Emeritus Professor BVB College of Engineering and Technology Hubli, Karnataka Published by DOWNLOADED FROM www.CivilEnggForAll.com I.K. International Publishing House Pvt. Ltd. S-25, Green Park Extension Uphaar Cinema Market New Delhi–110 016 (India) E-mail: [email protected] Website: www.ikbooks.com ISBN: 978-93-84588-31-1 © 2015 I.K. International Publishing House Pvt. Ltd. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or any means: electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission from the publisher. Published by Krishan Makhijani for I.K. International Publishing House Pvt. Ltd., S-25, Green Park Extension, Uphaar Cinema Market, New Delhi–110 016 and Printed by Rekha Printers Pvt. Ltd., Okhla Industrial Area, Phase II, New Delhi–110 020 DOWNLOADED FROM www.CivilEnggForAll.com Preface Civil Engineering is a vast subject. After graduation a civil engineer must remember important points on every aspect of civil engineering. With this objective, competitive examinations are conducted to select candidates for admission to postgraduate courses, UPSE, BHEL, ONGC, NTPC and many more organizations. As it is difficult to go through all books on various subjects, this book has been prepared to enable the candidates to glance through all the subjects and prepare themselves for the competitive examinations. Each aspect with important formulae, equations, definitions, principles, etc., is first presented briefly and then an exhaustive set of objective type questions with keys at the end are presented. The author hopes all UG students, students preparing for competitive examinations and practising engineers will find this book useful. Although every care has been taken to ensure accuracy, yet some errors might have crept in, the author will be thankful, if they are pointed out along with suggestions to further improve the book. S.S. Bhavikatti DOWNLOADED FROM www.CivilEnggForAll.com Contents Preface 1. Materials of Construction 1.1 Stones 1.2 Characteristics of Good Building Stones 1.3 Timber 1.4 Bricks 1.5 Clay Products 1.6 Ferrous Metals 1.7 Non-Ferrous Metals 1.8 Alloys 1.9 Cement 1.10 Mortar 1.11 Cement Concrete 1.12 Concreting 1.13 Lime 1.14 Pozzolanas 1.15 Paints, Varnishes and Distempers 1.16 Miscellaneous Materials Multiple-Choice Questions 2. Building Construction 2.1 Introduction 2.2 Foundations 2.3 Roofs Multiple-Choice Questions 3. Surveying 3.1 Surveying 3.2 Errors in Surveying 3.3 Levelling 3.4 Permanent Adjustments of Dumpy level and Theodolite 3.5 Circular Curves 3.6 Precise Levelling Multiple-Choice Questions 4. Engineering Mechanics 4.1 Resultant and Equilibrium of System of Coplanar Concurrent Forces 4.2 Beams 4.3 Friction 4.4 Centre of Gravity and Mass Moment of Inertia 4.5 Work Energy MethodDOWNLOADED FROM www.CivilEnggForAll.com 4.6 Rotation of Rigid Bodies Multiple-Choice Questions 5. Strength of Materials 5.1 Introduction 5.2 Simple Stresses and Strains 5.3 Compound Stresses and Strains 5.4 Theories of Failure 5.5 Shear Force and Bending Moment Diagrams 5.6 Stresses in Beams 5.7 Torsion 5.8 Thin and Thick Cylinders and Spheres 5.9 Columns and Struts Multiple-Choice Questions 6. Structural Analysis 6.1 Introduction 6.2 Influence Lines 6.3 Cables and Suspension Bridges 6.4 Slope Deflection Method 6.5 Moment Distribution Method 6.6 Column Analogy Method 6.7 Influence Line Diagrams for Statically Indeterminate Beams 6.8 Analysis of Multistorey Buildings by Approximate Methods 6.9 Two Hinged Arches 6.10 Matrix Method of Structure Analysis 6.11 Plastic Analysis Multiple-Choice Questions 7. R.C.C. Design (As Per IS : 456-2000) 7.1 Methods of R.C.C. Design 7.2 Strength of Doubly Reinforced Sections 7.3 Limit State of Serviceability 7.4 Requirements of Reinforcements 7.5 Design of Circular and Odd Shaped Slabs 7.6 Yield Line Analysis of Slabs Multiple-Choice Questions 8. Steel Structures (As Per IS 800-2007) 8.1 Advantages and Disadvantages 8.2 Principle of Limit State Design 8.3 Bolted Connections 8.4 Welded Connections DOWNLOADED FROM www.CivilEnggForAll.com 8.5 Design of Tension Member 8.6 Design of Compression Members 8.7 Column Splice 8.8 Design of Beams Multiple-Choice Questions 9. Fluid Mechanics 9.1 Introduction 9.2 Kinematics of Fluid Motion 9.3 Dynamics of Fluids 9.4 Laws of Mechanics 9.5 Turbulent Flow in Pipes Multiple-Choice Questions 10. Hydraulic Machines 10.1 Turbine 10.2 Types of Hydraulic Turbines 10.3 Pumps Multiple-Choice Questions 11. Irrigation Engineering 11.1 Quality of Irrigation Water 11.2 Canal Irrigation System 11.3 Sedimentation Transport and Design of Channels 11.4 Cross Section of Canal 11.5 Waterlogging and Salinity of Soil 11.6 Diversion Head Works 11.7 Hydraulic Jump 11.8 Theories of Seepage 11.9 Canal Falls 11.10 Miscellaneous Canal Structures 11.11 Tank Irrigation Multiple-Choice Questions 12. Soil Mechanics and Foundation Engineering 12.1 Introduction 12.2 Properties of Soils 12.3 Permeability of Soil 12.4 Seepage 12.5 Compressibility and Consolidation 12.6 Shear Strength 12.7 Earth Pressure and Retaining Structure 12.8 Foundations 12.9 Soil Stabilization DOWNLOADED FROM www.CivilEnggForAll.com 12.10 Types of Foundations Multiple-Choice Questions 13. Environmental Engineering 13.1 Sources of Water 13.2 Sanitary Engineering Multiple-Choice Questions 14. Highway Engineering 14.1 Role of Transportation 14.2 Highway Construction 14.3 Traffic Engineering Multiple-Choice Questions 15. Railway Engineering 15.1 Introduction 15.2 Sleepers 15.3 Ballast 15.4 Geometric Design 15.5 Curves Multiple-Choice Questions 16. Tunnelling 16.1 Tunnel Drainage Multiple-Choice Questions 17. Docks and Harbour Engineering 17.1 Types of Harbours 17.2 Features of a Harbour Multiple-Choice Questions 18. Bridge Engineering 18.1 History of Bridges 18.2 Selection of Bridge Site Multiple-Choice Questions 19. Airport Engineering 19.1 Introduction 19.2 Terminal Area Multiple-Choice Questions DOWNLOADED FROM www.CivilEnggForAll.com 1 Materials of Construction 1.1 STONES Rocks from which stones are obtained may be classified in the following three ways: 1. Geological classification 2. Physical classification 3. Chemical classification. 1. Geological classification On the process of formation, rocks are classified as igneous rocks, sedimentary rocks and metamorphic rocks. (a) Igneous Rocks: These are the rocks formed by cooling of magma. These rocks are strong and durable. They are further classified as: Volcanic rocks: Cooling of magma at earth’s surface – extremely fine grained and glossy. Examples: Basalt and trap. Hypahyssal rocks: Cooling of magma at shallow depth – fine grained crystallized structure. Examples: Quartz, dolerite and gneiss. Plutonic rocks: Cooling of magma at considerable depth – very strong and crystalline structure. Examples: Granite and dolerite. (b) Sedimentary Rocks: Disintegrated rock material is carried by flowing water and deposited elsewhere. Year after year new layers of materials are deposited and consolidated under pressure, heat and chemical action. Hence, the rocks so formed are uniform, fine grained and bedded. Examples: sandstones, mudstones, limestones. (c) Metamorphic Rocks: These are the rocks formed after igneous rocks and sedimentary rocks undergo changes due to pressure, heat and chemical actions. These rocks have foliated structure. For example: Granite becomes gneiss. Basalt changes to schist and laterite Limestone changes to marble Mudstone becomes slate. 2. Physical classification Based on the structure, rocks may be classified as stratified, unstratified and foliated rocks. (a) Stratified Rocks: They have layered structure. Examples: Sandstones, limestones, mud-stones. (b) Unstratified Rocks: They possess crystalline and compact grains. Examples: Granite, trap, marble. (c) Foliated Rocks: They have foliated structure. Along the planes of foliation they split easily. These planes are not parallel to each other. 3. Chemical classification DOWNLOADED FROM www.CivilEnggForAll.com (a) Siliceous Rocks: Main constituent is silica. These rocks are hard and durable. Examples: Granite, trap, sandstone. (b) Argillaceous Rocks: Clay is the main constituent. These rocks are brittle. They cannot withstand shock. Examples: Slate, laterite. (c) Calcareous Rocks: Calcium carbonate is the main constituent. Examples: Limestone, marble. 1.2 CHARACTERISTICS OF GOOD BUILDING STONES 1. It should possess fine grained structure, uniform and pleasing colour. It should be free from soft patches, flaws and cracks. 2. The minimum strength of 3.5 N/mm2 is required for stone to be used for load bearing walls. 3. It should not absorb more than 5% water. 4. The specific gravity should not be less than 2.5. 5. In attrition test, it should not show wear of more than 2%. 6. Toughness index should be more than 10. 7. It should have good resistance to shocks and it should be durable. Quarrying It is the process of extracting stones from rockbed, located near the earth’s surface and exposed to sun. Quarrying may be done using hand tools, channeling machine or by blasting. (a) Quarrying using hand tools: In soft rocks hand tools like chisels, hammers, pick axes and shovels may be used. Heating technique is suitable for getting aggregates. Wedging technique is suitable for quarrying in thin bedded rocks. (b) Quarrying using channelling machine: This is suitable for large size quarrying in soft rocks like marble and limestone. Channels are 50 to 75 mm wide and 2.4 to 3.6 m deep. After channelling with machine wedges and drills are used to get stones. (c) Quarrying by blasting: It consists of boring, charging, tamping and firing. The gas produced in the blast tries to come out by breaking the rock in all directions and succeeds in escaping along the Line of Least Resistance (LLR). Dressing of stones The aim of preliminary dressing is to bring the size of stone approximately to the required size and reduce the transportation cost to great extent. Final dressing is as per the requirement of the user. The different methods of final dressing are: (1) Hammer face; (2) Chisel drafted face; (3) Polished face and (4) Tooled finish. Seasoning of stones The process of removing sap from the pores is known as seasoning. The best method of seasoning is to allow the stones to dry for a period of 6 to 12 months in a shed. Preservation of stones The following preservatives are used: (1) Linseed oil; (2) Solution of alum and soap; (3) Solution of barium hydroxide; (4) Coal tar; (5) Paint and (6) Paraffin. Tests on stones Field Tests 1. Smith’s test: It is to check whether the FROM DOWNLOADED stone contains muddy substance. A sample of stone is kept www.CivilEnggForAll.com in a glass of distilled water for 24 hours and stirred well to remove muddy substance. 2. Toughness test: Stone is hit with a hammer and metallic sound is indication of strong stone. 3. Hardness test: Mohr’s hardness may be found by scratching the stone with knife. Laboratory Tests 1. Crushing strength test: 40 × 40 × 40 mm cubes are used for testing. Load is applied in a compression testing machine at the rate 14 N/mm2 per minute. A stone with crushing strength more than 100 N/mm2 is treated as good stone. 2. Water absorption test: For good stone water absorption after 24 hours immersion in water, should not exceed 0.60. 3. Attrition test: Los Angeles abrasion test is conducted to find the resistance of the stone to surface wear. Los Angeles value recommended are (a) for bitumen mix: 30%, (b) for base course 50%. 4. Impact test: Impact testing machine consists of a frame with guides. A metal hammer weighing 13.5–15 kg falls from a height of 380 mm. Recommended values for various works are For wearing coat 30% For bituminous mechadam 35% For water bound mechadam 40% 5. Acid test: Sandstones are checked for the presence of calcium carbonate. Sample of 50–100 gm of stone is kept in 1% hydrochloric acid for seven days. If calcium chloride is present, edges are broken and powder is formed. Common building stones Basalt, granite, sandstones, limestones, marble, quartzite, laterite and slate. Solid and hollow concrete blocks are known as artificial stones. 1.3 TIMBER Living tree, yielding good timber is called standing timber. After felling and separating branches it is known as rough timber. When bark is removed and stem is roughly converted into pieces of suitable length it is known as log. After the log is seasoned and converted into commercial sizes like planks, battens, posts and beams, it is known as converted timber. Classification 1. On the basis of mode of growth timber is classified as exogenous and endogenous. Exogenous trees grow outward adding a distinct ring every year while endogenous trees grow inwards. Example of exogenous trees are mahogony, sal, teak , babul while examples of endogenous trees are bamboo and cane. Exogenous trees are further classified as coniferous and deciduous. Coniferous trees have cone shape and their leaves do not fall till new ones grow. Deciduous trees have broad leaves and they fall in autumn and new ones appear in the spring. In the cross section of deciduous trees the following components are clearly visible from inside to outside. Pith, heartwood, sapwood, cambium layer, inner bark, outer bark and medullary rays. Sapwood contains annual rings, count of which gives the age of the tree. 2. Classification based on durability: Durability test is conducted by Forest Research Institute of India, Dehradun by burrying 600 × 50 ×FROM DOWNLOADED 50 sizewww.CivilEnggForAll.com specimen upto half their length and observing them over several years. Then timber is classified as (a) High durability: Average life of more than 10 years (b) Moderate durability: Average life 5 to 10 years (c) Low durability: Average life is less than 5 years. 3. Classification based on grading: On the basis of strength, defects, etc. IS: 12326–1976 classifies timber as special grade, Grade – I and Grade – II. 4. Classification based on Availability: X : Most common, 1415 m3 or more every year Y : Common, 335 m3 to 1415 m3 per year Z : Less common, less than 335 m3 every year. Seasoning of timber Seasoning is the process of reducing moisture content in a freshly cut tree to the desired level. Seasoning makes timber more durable and stable. The various methods of seasoning used are: – Natural seasoning: Air seasoning or water seasoning. – Artificial seasoning: Boiling, kiln seasoning. – Chemical seasoning or electrical seasoning. Conversion of timber Market names of converted timber are battens, plank, pole, scanting, beams, etc. They are available in different sizes and length. They are obtained by sawing logs. The various methods adopted for sawing are: ordinary, quarter, tangential and radial. Defects in timber Defects may be due to natural forces, attack by fungi or insects or due to erroneous seasoning. The defects due to natural causes are knots, shakes, rind galls, upsets, twisted fibres, wind cracks, burls, dead wood, foxiness and stain. Preservation of timber The widely used preservatives are coal tar, solignum paints, chemical salt, creosote and ASCU. ASCU is a special preservative developed by FRI, Dehradun. Industrial timber Veneers, plywood, fibreboards, particle boards, block boards, hard boards and Glulam. Indian timber trees Babul, Bamboo, Casurina, Deodar, Jack, Mango Mahogany, Rosewood, Teak, Sandalwood, Sisso. 1.4 BRICKS Standard sizes are 190 × 90 × 40 mm, with mortar the size comes out to be 200 × 100 × 50 mm. However, the old size of giving masonry of are still used in many parts of India. Clay suitable for making bricks contain Alumina – 20 to 30% is desirable Silica – 50 to 60% is desirable DOWNLOADED FROM www.CivilEnggForAll.com Lime – 5% is desirable Iron oxide – 5 to 6% Magnesia – A small quantity only Pebbles, vegetable and organic matter, excess lime, iron pyrites, sulphates of calcium and potassium are harmful. Manufacture of bricks involves preparation of clay, moulding, drying and burning processes. 1. Preparation of clay: It involves unsoling, digging, cleaning, weathering, blending and tempering; pug mills are used for tempering. 2. Moulding: It may be by hand moulding or by machine moulding. 3. Drying: It may be by natural drying or by artificial drying. 4. Burning: It may be in clamps or in kilns. Intermittent and continuous kilns are used depending upon the demand in the locality. Bull’s trench kiln, Hoffman’s kiln and Tunnel kilns are the continuous kilns. Classification of Bricks 1. Based on strength, bricks are classified as class 3.5, 5.0, etc. to mean compressive strength is 3.5 N/mm2, 5.0 N/mm2, etc. Each class is subdivided into A and B on the basis of tolerances in sizes. 2. However, in practice the bricks are classified as first, second, third and fourth class. The following types of special bricks are also available in markets: (1) High duty bricks; (2) Perforated bricks; (3) Hollow bricks; (4) Specially shaped bricks; (5) Fire clay bricks; (6) Paving bricks; (7) Facing bricks; (8) Soling bricks; (9) Sewer bricks. Tests on Bricks 1. Field tests: Observing size, colour, structure, hardness by scratching, sound test by striking two bricks with each other and strength test by dropping from a height of 1 m. 2. Laboratory tests conducted on bricks are: (a) Crushing strength test; (b) Absorption test; (c) Shape and size test; (d) Efflorescence test. Requirement of good bricks are: Compressive strength > 3.5 N/mm2 Water absorption 20% Variation in sizes should be within the tolerances prescribed by code. They should not show white patches when soaked in water for 24 hours. To meet local requirement, the following materials substitute for bricks: 1. Stabilized soil bricks; 2. Sand + lime blocks; 3. Fly ash bricks; 4. Concrete blocks. 1.5 CLAY PRODUCTS Apart from bricks, the following clay products are used by burning, glazing and vitrifying clay. (1) Tiles; (2) Terracotta; (3) Earthenware and (4) Stoneware. 1. Tiles Different types of tiles used are roofing tiles, ceiling tiles, ridge tiles, flooring and wall tiles, drain tiles. DOWNLOADED FROM www.CivilEnggForAll.com The following roofing tiles are used in India: (a) Half round tiles; (b) Corrugated tiles: (c) Pan tiles; (d) Allahabad tiles and (e) Mangalore tiles. Ceiling tiles are flat tiles provided under roofing tiles to give good appearance when viewed from below. Ridge tiles are specially shaped tiles to cover ridges in sloping roofs. Clay tiles, glazed tiles and vitrified tiles are used for flooring and to give finishing to walls. Drain tiles are laid in waterlogged areas to drain the water. 2. Terracotta Terracotta means baked earth. It may be manufactured in different colours also. There are two types of terracotta, viz. porous terracotta and polished terracotta. They are used for making art pieces and lavatory fittings. 3. Earthenware It is a type of terracotta in which the moulded product is burnt at low temperature to get semi-vitrified surface. These products are used for making cheap lavatory fittings and drain pipes. 4. Stoneware These are the pipes manufactured from refractory clays to which ground flint and crushed pottery are added and ground. During grinding pigments are also added. They are produced under pressure and then burnt at high temperature. They are used for making wash-basins, gully traps, jars and sewer pipes. 1.6 FERROUS METALS Metals which contain iron predominantly are termed ferrous metals. By varying carbon content slightly, ferrous materials of different varieties are manufactured. By hot rolling, cold drawing and heat treatment properties of ferrous materials can be modified. Cast iron, wrought iron and steel are the three popular varieties. 1. Cast iron Carbon content is 2 to 4%. The varieties of cast iron are: Grey cast iron, white cast iron, molten cast iron, chilled cast iron, toughened cast iron, ductile cast iron and malleable cast iron. Cast irons are coarse, crystalline and fibrous. They cannot be welded. They are used for water pipes, sanitary pipes and manhole covers. They are also used for making ornamental castings like gates, lamp posts, spiral railings, rail chairs etc. 2. Wrought iron It contains less than 0.15% carbon. It is fibrous and has silky lustre. It can absorb shocks. It is used for making nails, nuts, bolts, chains, roofing sheets, grills and straps. 3. Steel It contains 0.25 to 1.5% carbon. It is equally strong in tension and compression. It is suitable for all construction purposes. The types of steel are mild steel, medium carbon steel, high carbon steel. In the market they are available as rolled steel sections, tubes, flats, plates, sheets, corrugated sheets, expanded metal, bars and weld meshes. Thermo-mechanically treated (TMT) bars are manufactured by sudden quenching of red hot steels by spraying water, which results into high strength at the surface while the core portion is mild steel. These are ideally suited for R.C.C. works. 1.7 NON-FERROUS METALS Copper, aluminium, zinc, lead and tin are commonly used non-ferrous materials. 1. Copper By roasting, smelting, converting DOWNLOADED and electrolytic FROM refining copper ores like cuprite, glance, www.CivilEnggForAll.com malachite or copper pyrites, copper is produced. Market forms of copper are ingots sheets, wires and tubes. Copper is brown in colour but becomes greenish when exposed to atmosphere. It is malleable, ductile, a good conductor of heat and electricity, copper wires are used as electric cables. Copper straps are used as electric conductors and for closing construction joints. It is used as an alloy for making brass and bronze. 2. Aluminium Aluminium is extracted mainly from bauxite (Al2O3 2H2O). It is silvery white with bluish tinge. Its strength-weight ratio is favourable for construction. It is marketed in the following forms: ( 1) Casting based, (2) Extrusion based, (3) Foil and powder form, (4) Sheet form, and (5) Wires. Aluminium is used for doors, windows, partitions, decorative laminates, false ceiling, cable trays, sealing construction joints, transmitting electricity and for making paints. 3. Zinc Zinc ores are zinc calamine (ZnCO3) which contains 65% zinc and zinc blende (ZnS) which contains 50% zinc. When heated at 1100°C, zinc is liberated in the form of vapour which is collected and condensed. Zinc is a bluish white metal which is a good conductor of heat and electricity. It is used for making electrical cells and batteries, for galvanizing iron plates and in making paints and brass. 4. Lead Lead is extracted from the ore galena (PbS), which contains 86% lead. The ore is roasted, mixed with coke, smelted in blast furnace and reverberatory furnace. It is bluish grey in colour. It is poisonous. It is used as pigments in paints, for making storage battery solders and for making sanitary fittings. 5. Tin Tin ore is found as cassiterite (SnO2). The ore is crushed, roasted, smelted and refined by electrolysis. It is a silvery white lustrous metal. It withstands corrosion. It is used to provide protective coating to iron, copper, brass and lead. It is used for silvering mirrors and its foils are used for protecting food products. 1.8 ALLOYS Alloy is an intimate mixture of two or more metals. Aluminium alloys, copper alloys and steel alloys are commonly used alloys. 1. Aluminum alloys (a) Duralumin; (b) Aldural; (c) Aluminum bronze; (d) Y-alloy. 2. Copper alloys Brass and bronze are copper alloys. Brass is the alloy of copper and zinc. White brass, yellow brass, red brass, delta metal, cartridge brass and low brass are different types of brasses. Bronze is an alloy of copper, tin and minor percentage of other materials. Beryllium bronze, prospher bronze, green metal, bell metal, speculum metal are different types of bronzes. 3. Alloys of steel Alloying of steel with other metals is made to increase strength, hardness, toughness, resistance to wear. Varieties of steel alloys found in market are: (1) Stainless steel (2) Nickel steel (3) Tungsten steel (4) Invar steel (5) Manganese steel (6) Molybdenum steel and (7) Chromium steel. 1.9 CEMENT DOWNLOADED FROM www.CivilEnggForAll.com Cement is a reliable bonding material. It is obtained by burning calcareous material (lime) and argillaceous material (clay) and then grinding. Cement was first produced by Joseph Aspidin, a mason from England. As its colour resembled a variety of sandstone found in Portland, he named it Portland cement (1842). Limestones containing 20 to 40 per cent clay may be burnt and crushed to powder to get natural cement. Best variety of natural cement is known as Roman cement. Artificial cement is manufactured by mixing argillaceous and calcareous materials in suitable proportions and burning at a temperature 1400°C to 1450°C to get clinkers, which are then ground to get cement. Ordinary Portland cement (OPC) contains lime (60 – 67%), silica (17 – 25%), alumina (3 – 8%) iron oxide (0.5 – 5.0%), calcium sulphate (3 – 4%), magnesia (0.1 – 3.0%), sulphur oxide (1 – 3%) and alkalies (0.4 – 1.3%). Lime imparts strength. Silica contributes to strength by forming dicalcium and tricalcium silicates. Excess silica prolongs setting lime. Alumina imparts quick setting property. Iron oxide provides colour, hardness and strength. Calcium sulphate increases the initial setting time. Magnesia provides hardness and colour. Sulphur makes cement unsound. Alkalies, if in excess, cause efflorescence. OPC contains the following chemical compounds 1. Tricalcium silicate 3CaO◊ SiO2 (C3S) 40% 2. Dicalcium silicate 2CaO◊ SiO2 (C2S) 30% 3. Tricalcium aluminate 3CaO◊ Al2O3 (C3A) 11% 4. Tetracalcium alumino ferrite. 4CaO◊ Al2O3 Fe2O3 (C4 AF) 11% It also contains small quantities of impurities like calcium oxide (CaO) and magnesium oxide (M2O). When water is added C3A is first to react and sets generating heat C3S hardens early and develops strength in first 28 days. C2S hydrates slowly and increases strength over a year and contributes to ultimate strength. C4 AF is a comparatively inactive compound. Physical requirements of OPC are: 1. Fineness: The material retained on 90 micron sieve should not be more than 10%. In terms of specific surface, it should not be less than 2250 cm2/gm [225 m2/kg]. 2. Setting time: Minimum initial setting time should be 30 minutes and maximum final setting time should be 600 minutes. 3. Soundness: After the test is conducted in Le Chatelier mould, the indicator should not show more than 10 mm widening. 4. Compressive strength: Mortar cubes of size 70.6 mm with 1 part cement, 3 parts of standard sand with specified water should give the strength as shown in Table 1.1. Table 1.1 Compressive strength of cement in N/mm2 Age Grade 33 Grade 43 Grade 53 3 days 16 DOWNLOADED 23 FROM www.CivilEnggForAll.com 27 7 days 22 33 37 28 days 33 43 53 Manufacture of cement consists of mixing, burning and grinding processes. 1. Mixing: It may be wet process or by dry process. In wet process wash mill is used which is a heavy cylinder of 2.5 to 3.0 m in diameter and 9 to 12 m in length. It is kept slightly inclined to the horizontal and can rotate at 15–20 revolutions per minute. The cylinder is provided with steel balls. 2. Burning: Burning is carried out in a rotary kiln, which is a steel tube of diameter 2.5 to 3.0 m and length 90 to 120 m, placed at an inclination 1 in 25 to 1 in 30. It rotates at a rate of 1 to 3 rotation per minute. Coal dust is injected from lower end and mix is fed from top end. The temperature at feed end is 1400°C to 1500°C. 3. Grinding: The clinkers from rotary kiln are fed into a ball mill or tube mill. During the process of grinding about 3 to 4 per cent of gypsum is added. The ball mill or tube mill contains steel balls. Storage of cement: Cement absorbs moisture from air and hydrates, which results into loss of strength. Hence, cement should be stored on a raised platform in a covered room. First- in-first-out rule should be used while taking out cement. The drainage system on the roof and around the storage should be well maintained. Storage period should be as little as possible. Types of cement are 1. OPC: 33 grade, 43 grade and 53 grade (OPC) 2. Portland Pozzolana cement (PPC) 3. Fly ash cement 4. Blast furnace slag cement 5. Acid resistant cement 6. Sulphate resistant cement 7. High alumina cement 8. Quick setting cement – obtained by reducing the quantity of gypsum. 9. Rapid hardening 10. Expanding cement 11. Low heat cement 12. Hydrophobic cement 13. White cement 14. Coloured cement Fine and Coarse Aggregates Sand, gravel, crushed stones which are the products of weathering or crushing of rocks are known as aggregates. Sources of fine aggregates on the basis of which sand is classified are: sea sand, river sand, stream sand, pit sand and manufactured sand. On the basis of grains size sand is classified as fine sand, coarse sand and gravelly sand. IS code classifies sand as grading zone - 1, Grading zone - 2, Grading zone - 3 and Grading zone - 4 on the basis of percentage of sand passing through different sizedDOWNLOADED sieves. FROM www.CivilEnggForAll.com Function of sand: It subdivides the cement paste into thin films and allows it to spread and adhere. It allows carbon dioxide from air to penetrate and improve setting. It prevents shrinkage and adds to density of mortar. It fills the gap between building blocks and gives level surface to mortar. Bulking of sand: The increase in volume due to moisture content is known as bulking of sand. It is due to formation of thin films around sand particles. Increase in volume is as high as 30 – 37 per cent. At around 8% of moisture content, there is maximum bulking. Finer the sand more is the bulking. After about 20% moisture content, thin films start breaking and volume reduction takes place. A good sand has the following properties: (1) Chemically inert; (2) Hard; (3) Contains sharp and angular grains; (4) Free from salt, clay and organic matter; (5) Well graded. The field tests are possible to find presence of clay, salt and organic impurities. The size and shape of gains may be felt by touching it with fingers. Laboratory tests may be conducted to ascertain grading, bulking and to find fineness modulus. To determine fineness modulus sieves to be used are 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron. The cumulative percentage of weight retained on the above sieves divided by 100 gives fineness modulus (FM). If FM is between 2.20 and 2.60 it is fine sand, 2.6 to 2.9 FM indicates it is medium sand and more than 2.9 FM indicates it is coarse sand. Coarse aggregate gives mass to concrete. For structures like abutment, retaining walls and bed concrete 40 mm down size aggregates are used. For normal R.C.C. works like flooring roofing and columns 20 mm down size aggregates are preferred. For thin members 12.5 mm sized aggregates are used. The various tests conducted on coarse aggregates are to determine: 1. Flakiness and elongation indices 2. Fineness and grain size distribution 3. Specific gravity and water absorption 4. Clay, silt and dust content 5. Resistance to crushing 6. Resistance to impact 7. Resistance to abrasion. 1.10 MORTAR Mortar is an intimate mixture obtained by adding water to dry mixture of sand and binding material like clay, lime or cement. Classification of Mortar: 1. On the basis of bulk density: Heavy weight, if weight is more than 15 kN/m3, light weight, if its weight is less than 15 kN/m3. 2. On the basis of application: Brick laying mortar, finishing mortar. 3. On the basis of binding material: Mud DOWNLOADED FROM mortar, lime mortar, surkhi mortar, cement mortar and www.CivilEnggForAll.com gauged mortar. The proportions of cement to sand for various works used are show in Table 1.2. Table 1.2 Cement-sand proportions S. No. Name of work Cement: sand 1. Brickwork below ground level 1 : 3 to 1 : 4 2. General brickwork and stone masonry 1:6 3. For arch work 1:3 4. Damp-proof course 1:2 5. External plastering and ceiling plastering 1:4 6. Internal plastering 1 : 5 to 1 : 6 7. Pointing 1 : 2 to 1 : 3 The strength obtained with different proportion is as shown below: (1) 1 : 3 Mix – 10 N/mm2; (2) 1 : 4 Mix – 7.5 N/mm2; (3) 1 : 5 Mix – 5.0 N/mm2; (4) 1 : 6 Mix – 3.0 N/mm2; (5) 1 : 8 Mix – 0.7 N/mm2. Cement mortar may be prepared by hand mixing or by machine mixing. Mortars with special properties are also used: Fire resistant, sand absorbing, X-ray shielding, packing mortar and decorative mortars are the special mortars. 1.11 CEMENT CONCRETE Cement concrete is an intimate mixture of cement, sand, coarse aggregates and water. Occasionally some admixtures are added to introduce special properties. Water lubricates aggregates, activates chemical reactions and give workability to mix. However, the quantity of water to be used should be determined carefully since workability of concrete increases with quantity of water but the strength decreases. Various admixtures used with concrete are: (1) Accelerators; (2) Retarders; (3) Air entraining agents and (4) Colouring agents. Important properties of concrete in plastic stage (green concrete) are workability, segregation and bleeding. The important properties of hardened concrete are: (1) Strength; (2) Resistance to wear; (3) Impermeability and (4) Durability. IS code classifies concrete mix as M 20, M 25, etc. which means mix of strength 20 N/mm2, mix of strength 25 N/mm2, etc. at the age of 28 days. IS: 10262–1982 and SP 23–1982 give detailed procedure to design concrete mix of required strength. For small works nominal mixes as shown is Table 1.3 may be used. Table 1.3 Normal mixes for minor works Mix DOWNLOADED Proportion FROM Nature of works www.CivilEnggForAll.com M : 7.5 1:4:8 For bed concrete M : 10 1:3:6 For sill concrete and mass concrete works M : 15 1:2:4 For R.C.C. structural elements M : 20 For water retaining structures M : 25 1:1:2 For heavily loaded columns, beams, etc. 1.12 CONCRETING It involves mixing, transporting, placing, compacting and curing. 1. Mixing: One can adopt hand mixing or machine mixing. Coarse aggregate and fine aggregates are dry mixed, then cement is mixed till uniform colour is seen to the dry mix. The required quantity of water is mixed gradually while mixing process is kept continuous. 2. Transportation: Care should be taken to avoid segregation during transport. 3. Placing: Concrete should be placed to its final position by dropping it as close to final position as possible, in any case not more than 0.8 m. 4. Compacting: To remove entrapped air compacting of concrete is necessary. It may be hand compacting or by using vibrators. Over-compacting should be avoided to avoid segregation. 5. Curing: It is the process of maintaining satisfactory moisture and temperature in a freshly laid concrete. Curing should be done well in first 2 weeks and continued for another 1–2 weeks. If curing is not satisfactory shrinkage cracks may develop and durability is reduced. The various methods of curing are: (1) Spraying water; (2) Covering with gunny bags; (3) Ponding; (4) Steam curing and (5) Applying curing compounds. Different Concrete Works 1. Plain concrete 2. R.C.C. 3. P.S.C. 4. Precast concrete 5. Special concrete. To meet the requirements of special situations, the following types of concrete are manufactured: 1. Fibre reinforced concrete (FRC). 2. Polymer impregnated concrete (PIC) 3. High performance concrete 4. Light weight concrete 5. Self-compacting concrete. Tests on Concrete To measure workability slump test, compaction factor test or Vee-Bee consistometer tests are conducted. To find the strength, compression tests are conducted on 150 × 150 × 150 mm cubes after 28 days. 1.13 LIME DOWNLOADED FROM www.CivilEnggForAll.com Lime has been used as cementing material from ancient times. It contains clay (8 to 10%), magnesium carbonate (not more than 30%) and very small quantities of soluble silica, alkalies, sulphate and iron apart from the main constituent calcium carbonate. Lime is classified as fat lime, hydraulic lime and poor lime. Fat lime contains 95% of calcium oxide. When water is added, it slakes vigorously and its volume increases 2 to 2.5 times. Hydraulic lime sets by chemically combining with water. It is classified as feeble hydraulic lime (5 to 10% clay), moderately hydraulic lime (10 to 20% clay), eminently hydraulic lime (20 to 30% clay). It is used for making mortar to be used for plastering and in damp-proof constructions. Lime containing more than 30% clay is poor lime. Manufacture of lime involves preparation, burning and hydration (slaking). For burning clamps or kilns are used. The kiln may be intermittent or continuous. IS: 1624–1974 specifies various tests to assess the quality of lime. The tests prescribed are: (1) Physical properties tests; (2) Acid tests; (3) Heat test; (4) Ball test; (5) Impurity test; (6) Plasticity test; (7) Workability test. 1.14 POZZOLANAS Pozzolana is defined as a siliceous material that does not possess cementation property, but reacts with lime in the presence of water at normal temperature to form compounds. Pozzolana is added to fat lime to produce hydraulic lime. Addition of pozzolana to cement makes product cheap, which is known as PPC. It gets strength slowly but final strength is same as that of OPC. It possesses better impermeability compared to OPC. Addition to concrete helps in getting dense concrete and it reacts with free lime. Hence, chances of blisters appearing latter is eliminated. Heat of hydration is reduced, which is essential in mass concrete works. Surkhi, blast furnace slag, fly ash, silica fame and rice husk ash are the pozzolanic materials. 1.15 PAINTS, VARNISHES AND DISTEMPERS The surfaces of walls, ceiling, wood and metal works are coated with paints, varnishes or distempers to protect them and give them good appearance. Paint is a mixture of solid pigments in liquid vehicles. The essential constituents of oil-borne paints are base, vehicle, solvent, pigment, filler and drier. 1. Base: It is a solid substance in a fine state forming bulk of the paint. White lead, red lead, zinc oxide, iron oxide, aluminium powder are commonly used base materials. 2. Vehicle: The liquid substance that holds the ingredients of paint is known as vehicle. Linseed oil, tung oil, poppy oil, nut oil, etc., are the commonly used vehicles. 3. Solvents: Solvents are the paint thinners. The common solvents are turpentine, petroleum spirit and naptha. 4. Pigment: Pigments provide colour to the paint Black – Lampblack, charcoal black Brown – Burnt umber, burnt sienna Blue – Persian blue, ultramarine DOWNLOADED FROM www.CivilEnggForAll.com Green – Chrome green, copper sulphate Red – Red lead, venetian red Yellow – Zinc chrome, raw sienna chrome yellow. 5. Fillers: Fillers are inert materials added to reduce cost of paint. They make paint durable. Magnesia, alumina, gypsum, silicate, barite are the commonly used fillers. 6. Driers: Its function is to absorb oxygen from air and supply it to the vehicle. It is added just before painting. They are compounds like lead, manganese and cobalt. Types of paints are 1. Oil paint: These paints contain white lead as base. 2. Enamel paint: This paint is prepared by adding white lead or zinc to varnish. It is desirable to provide titanium under coat. It may be used for exterior walls also. 3. Emulsion paint: It contains binding material like polyvinyl acetate and polystyrene. Cobalt and manganese are the pigments and driers. The paint becomes surface dry within 15 minutes and hardens in 2 hours. The surface is washable. 4. Cement paint: It consists of white or coloured cement as base. It is available in the form of powder, which is mixed with water and used. 5. Aluminium paint: It consists of finely ground aluminium particles in suspension, in spirit or oil varnish. It is visible in darkness. 6. Bituminous paint: It is manufactured by dissolving asphalt of vegetable bitumen in oil or petroleum. It is black in colour. It is used for painting portions of wooden posts buried underground. 7. Synthetic rubber paint: It is prepared by dissolving chlorinated rubber in a solvent. It may be applied to concrete surfaces also. 8. Celluloid paint: It is prepared by dissolving celluloid sheets or nitro cotton in petroleum. Castor oil is added to improve adhesive property. It is used for painting vehicles. 9. Asbestos paint: It consists of fibrous asbestos. It is used for stopping leakages in metal roof, basements. It is used for painting gutters. 10. Plastic paint: It consists of plastic as a base and water as a thinner. It gives attractive colours. This is widely used for painting walls in auditoriums and show rooms. 11. Anticorrosive paint: It consists of linseed oil as vehicle and lead or zinc chrome as base. Finely ground sand is added as filler. It is black in colour and gives protection from corrosion. Painting 1. Plastered surfaces Emulsion paints may be applied after a curing period of 4 – 6 weeks. Final coat is to be applied after 6 – 12 months only. Before painting the surface should be made dust free. For new surfaces primer coat is required. 2. Concrete surface Usually, two coats of cement paint are required. Painted surface should be cured for 10 – 15 days. 3. Wood surface Before painting a new surface all nail heads should be punched to a depth of 3 mm. The surface should beDOWNLOADED made free fromFROM loose particles, dust and grease. Knots if any should be www.CivilEnggForAll.com levelled and two coats of varnish applied. Fill all cracks, dents, loose joints with putty. Apply primer, two undercoats before the finishing coat. In case of old wood works clean the surface with sand paper and pumice stone wash with caustic soda solution of 200 gm in a litre of water. Apply primary coat, undercoat and finishing coats. 4. Iron and steel surface Remove dust with wire brushes. Remove grease by washing with caustic soda. Then apply the coats. Varnishes: Varnish is a transparent solution containing resinous solutions like amber, coal, shellac, gum, etc. Solvent is turpentine or alcohol or water. The process of applying varnish is known as varnishing. It makes surface glossy. Distemper: It is also called water paint. It is a paint with chalk as base and water as carrier. It is readily available in the market in the form of powder. There are two types of distempers: dry distempers and oil bound distempers. 1.16 MISCELLANEOUS MATERIALS 1. Glass and glass wool It is manufactured by fusion of silica with varying proportions of oxides of sodium, calcium, potassium and magnesia. They are fabricated by blowing, drawing, pressing, rolling or casting. After annealing they are given treatment by tempering, opaque making, silvering, bonding or cutting. It can be made stronger than steel and lighter than cork. Types of glass are many: (1) Common glass; (2) Soda lime glass; (3) Potash lime glass; (4) Potash lead glass; (5) Coloured glass; (6) Special glasses. Special glasses are fibre glass, wired glass, safety glass, bullet proof glass, shielding glass, ultraviolet ray glass, structured glass, glass blocks, ribbed glass, perforated glass and glass wool, etc. 2. Plastics Plastic is a natural synthetic material, which has a property of being plastic at some stage of its manufacture. Synthetic material nay be phenol, formaldehyde, cellulose vinyl, etc. At present there are more than 1000 varieties of plastic. Synthetic of plastics are polymers. Polymerization is the process in which relatively small molecules, called monomers combine chemically to produce a very large network molecules, called polymers. Classification of the plastics may be on various basis. 1. On the basis of structure: Homogeneous plastics and heterogeneous plastics. 2. On the basis of physical and mechanical properties. Rigid plastics, semi-rigid plastics, soft plastics and elastomers. 3. On the basis of thermal properties: Thermoplastics and thermosetting plastic. Thermoplastics soften on heating and harden on cooling. The process of softening and hardening can be repeated several times. Thermosetting plastic undergo chemical changes at 127 – 177° C and set into permanent shape under pressure. Reheating will not soften them. Advantages of plastic are — they can be moulded easily, do not rust, resist chemical action, light in weight and possess high strength to weight ratio. Disadvantage is that they have low modulus of elasticity. DOWNLOADED FROM www.CivilEnggForAll.com 3. Glass fibre reinforced plastics (GFRP) In these glass fibres provide stiffness and strength while resin provides a matrix to transfer load to fibres. GFRP is used for door and window frames, partition walls, roofing sheets, skylights, water tanks, for making chairs and tables. 4. Asbestos Asbestos is a naturally available mineral substance. It is fire-proof, acid-proof. It is a good insulator of heat and electricity. It is used with cement to produce asbestos cement sheets for roofing, wall panelling, to cover fuse and electric boxes, for making downtake pipes, etc. 5. Bitumen, asphalt and tar These are called bituminous materials and their main constituent is hydrocarbon. (a) Bitumen: It is obtained by fractional distillation of crude petroleum. It is specified by term penetration, say 80/100 means penetration of standard needle is 80 to 100 mm at a temperature of 25°C. It is used for damp proof course, roofing felt. (b) Asphalt: It is bitumen mixed with inert material like sand, gravel and crushed stone. It is found in natural form. It is artificially manufactured also. It is used for waterproofing floors and roofs, lining reservoirs and swimming pools, for grouting expansion joints. (c) Tar: It is obtained by destructive distillation of coal, wood or mineral tar. It is used for road work, anti-termite treatment and waterproofing. 6. Fly Ash It is a by-product in coal based thermal plants. Its particles can fly in ordinary air. At one time it was considered a nuisance but now it is used as a useful material in manufacturing bricks, for stabilizing soil and to improve workability of concrete. 7. Steel Putty It is a plaster filler which can be applied with knife to fill dents in steel plates. It has good adhesive property and dries hard. 8. Adhesive, sealants and joint fillers An adhesive is a material used to join two or more surfaces. Asphalt, shellac and cresin are natural adhesives which are used to glue papers. Rubber is another natural adhesive used to join plastic, glass and rubber. There are many synthetic varieties of adhesives like melamine resin, phenoil resin, urea resin and polyvinyl resin. They are used for joining plywood and laminated products. Starch glue, animal glue, casein glue (glue from skimmed milk), sodium silicate glue are also available for joining various materials. Sealants: Sealants are the substances used to seal cracks or joints between wall and window frames, glazing and window frame or between roofing sheets. Elastomeric sealants are most efficient. They are based on silicon, acrylic or polysulphide. Joints fillers: To prevent seepage of water through construction joints, these materials are used. They should be compressible and resilient. The common joint fillers used are built in strips of metals, bitumen treated felt and cork bound rubber. 9. Heat, electrical and sound insulating materials Thermal comfort may be achieved by providing air spaces by using aerated concrete, hollow blocks, using blast furnace slag in mortar and concrete and providing insulators and reflecting paints. DOWNLOADED FROM www.CivilEnggForAll.com Electric insulators are used to separate the conductors carrying electric current. Mica, asbestos, porcelain, rubber, leakalite are electrical insulators. Paraffin and chlorinated diphenyl are liquid insulators which are used in transformers. In refrigerators thermocol is used. In auditoriums and cinema halls, sound insulators are required. The commonly used sound insulators are cellular concrete, asbestos, gypsum plaster, pulp boards, perforated plywood, glass mineral wool, etc. 10. Waterproofing and damp-proofing materials Preventing passage of water from one side of a surface to other side under normal hydrostatic pressure is known as waterproofing while damp-proofing is to prevent transfer of water by capillary action. Bituminous materials, integral compounds, epoxy based materials, slurry coat and elastomeric materials are various waterproofing materials. 11. Thermocol It is a general-purpose crystal polysterene. It can be cut easily with knife or saw. It contains 3–6 million discrete cells/litre. It has insulating efficiency against heat, sound, humidity and shock. It is used as packing material and display board. 12. Epoxy It is a thermosetting polymer. It possesses excellent mechanical and adhesive properties. It is used with paints also. 13. Polyurethene It is a product produced by mixing polymeric diol or triol with a silicon surfactant and a catalyst. This has elasticity of rubber, combined with the toughness of metal. It is used for making gaskets, tiers, bushings, shoe soles, pipes, waterproofing chemicals, etc. 14. Geosynthetics These are synthetic materials made of nylon, PVC, polypropylene etc. They last long even when buried under soil. Geotextiles, geogrids, geomembranes and geocomposites are commonly used geosynthetics. These materials are used for soil stabilization. 15. Ferrocement Wire meshes embedded with cement and baby jelly is known as ferrocement. They are used for making door/window frames and shutters, partition walls, signboards, furnitures and even boats. 16. Cladding materials Cladding materials are used to enhance aesthetic appeal of walls, kitchen slab, stairs, roofs, ceiling, etc. Slate, granite, marble, clay tiles, mosaic, glass, wall papers etc. are the commonly used cladding materials in buildings. 17. PVC building products Polyvinyl chloride (PVC) is versatile plastic. Its properties can be easily modified by addition of other compounds. PVC pipes, door and window frames, partition walls, kitchen cabinets, tiles and false ceiling are very popular products. MULTIPLE-CHOICE QUESTIONS I. Stones 1. The rocks formed due DOWNLOADED to solidification ofFROM moltenwww.CivilEnggForAll.com mass are called (a) aqueous rocks (b) sedimentary rocks (c) metamorphic rocks (d) igneous rocks 2. Granite is an example of (a) aqueous rocks (b) sedimentary rocks (c) metamorphic rocks (d) igneous rocks 3. Solidification of molten magma at the surface of the earth results in the formation of (a) sedimentary rock (b) basalt and traps (c) granite (d) metamorphic rock 4. Solidification of molten magma within the earth’s crust results in the formation of (a) sedimentary rock (b) basalt and trap (c) granite (d) metamorphic rack 5. Sedimentary rocks are formed due to (a) solidification of molten mass (b) gradual deposition of materials like sand, clay, generally by setting water (c) alteration of original stones under heat and pressure (d) none of the above 6. In the options given in question No. 5, identify the process responsible for the formation of metamorphic rocks. 7. Under metamorphism, which of the following changes is correct? (a) granite changes to gnesis. (b) trap and basalt change into laterite. (c) limestones change into marble. (d) all the above 8. Granite has (a) crystalline, glossy and fused texture (b) foliated structure (c) layers of different compositions (d) none of the above 9. The principal constituent of argillaceous rock is (a) sand (b) lime DOWNLOADED FROM www.CivilEnggForAll.com (c) clay (d) all the above 10. Laterite is chemically classified as (a) calcareous rock (b) siliceous rock (c) metamorphic rock (d) argillaceous rock 11. Which of the following is an example of siliceous rock? (a) granite (b) gnesis (c) quartzite (d) all the above 12. Marble is an example of (a) aqueous rock (b) metamorphic rock (c) sedimentary rock (d) igneous rock 13. Slate is used for (a) building walls (b) road metal (c) manufacture of cement (d) roofing 14. Which one of the following takes polish very well? (a) basalt and trap (b) granite (c) sandstone (d) quartzite 15. The colour of granite is (a) grey (b) green (c) brown (d) all of these 16. A fine grained granite (a) can be polished well (b) can be used for exterior facing of buildings (c) offers higher resistance to weathering (d) all of the above 17. Siliceous sand subjected to metamorphic action is known as (a) laterite DOWNLOADED FROM www.CivilEnggForAll.com (b) murram (c) quartzite (d) dolomite 18. When quarrying is to be done in hard and compact rocks, the usual method employed is (a) wedging (b) using channeling machine (c) blasting (d) all of the above 19. Quarrying by using channeling machine is employed for quarrying in (a) soft rock (b) hard rock (c) sandstones (d) all the above 20. Heating technique of breaking rocks is suitable if the aim is to get (a) aggregates (b) slabs (c) building blocks (d) none of the above 21. The process of taking out stones of various sizes from natural rock is known as (a) dressing (b) seasoning (c) polishing (d) quarrying 22. The process of giving required shape and size to stones is known as (a) dressing (b) seasoning (c) polishing (d) quarrying 23. Boasted finish of dressing stone is (a) making non-continuous parallel marks (b) giving finish to a 20 mm margin only at edges (c) providing continuous lines on the face (d) working out 30–50 mm wide margin around the face with chisel 24. Dressing of the stone is made (a) immediately after quarrying (b) after three months of quarrying (c) just before using for building works (d) after seasoning 25. The most powerful explosive used in blasting DOWNLOADED FROM is www.CivilEnggForAll.com (a) gunpowder (b) guncotton (c) dynamite (d) cordite 26. Moisture absorption of a good stone should be less than (a) 1% (b) 5% (c) 8% (d) 12% 27. Most of the stones possess the specific gravity in the range of (a) 1.2 – 1.6 (b) 1.6 – 2.0 (c) 2.4 – 2.8 (d) 3.0 – 4.0 28. Which of the following has the lowest strength? (a) granite (b) sandstone (c) marble (d) laterite 29. Limestone used for manufacture of cement is (a) kankar (b) magnesium limestone (c) compact limestone (d) granular limestone 30. Which of the following has the highest crushing strength? (a) granite (b) gneiss (c) basalt (d) trap 31. Which of the following stone has the highest resistance to fire? (a) granite (b) limestone (c) sandstone (d) argillaceous material 32. Smith’s test on stone is to check (a) toughness (b) hardness (c) compressive strength (d) presence of muddy substance 33. Los Angeles testing machine is used to FROM DOWNLOADED find thewww.CivilEnggForAll.com following in stone (a) surface wear (b) hardness (c) compressive strength (d) presence of mud 34. Impact value of stone for road work specified are (a) wearing coat 30% (b) bituminous macadam 35% (c) water bound macadam 40% (d) all the above 35. Deterioration of stones takes place due to (a) temperature variation (b) freezing and thawing (c) rainwater (d) all of the above 36. Which one of the following is not a preservative of stone (a) coal tar (b) paraffin (c) linseed oil (d) ASCU Timber 37. After felling and separating branches the tree is known as (a) log (b) converted timber (c) rough timber (d) none of the above 38. Which one of the following does not belong to exogenous tree (a) deodar (b) pine (c) mahogany (d) bamboo 39. Which one of the following dose not belong to endogenous trees (a) teak (b) coconut (c) bamboo (d) cane 40. On the basis of durability test, Forest Research Institute of India, Dehradun, a tree is highl y durable if its average life is more than (a) 5 years DOWNLOADED FROM www.CivilEnggForAll.com (b) 10 years (c) 15 years (d) 20 years 41. The trees, of which leaves fall in autumn and new ones appear in spring are classified as (a) coniferous trees (b) deciduous trees (c) endogenous trees (d) none of the above 42. The oldest part of exogenous tree is (a) pith (b) heartwood (c) sapwood (d) cambium layer 43. Age of exogenous tree can be judged from (a) medullary rays (b) annual rings (c) cambium layer (d) inner bark 44. The layer between the dark and sapwood which is yet to be converted into wood is known as (a) pith (b) heartwood (c) softwood (d) cambium layer 45. Which one of the following is softwood (a) deodar (b) teak (c) sal (d) mahogany 46. Which one of the following is not a softwood: (a) oak (b) pine (c) deodar (d) bamboo 47. On the basis of availability, timber is classified as (a) I. II, III Class (b) grade I, II, and III (c) A, B, C Class (d) X, Y, Z Class 48. The main purpose of seasoning of timber is to DOWNLOADED FROM www.CivilEnggForAll.com (a) reduce moisture content (b) make it fire resistant (c) make it waterproof (d) none of the above 49. Seasoning makes timber (a) durable (b) light, strong and stable (c) resistant to fungi and termites (d) all of the above 50. Which of the following statements is not correct? (a) by kiln seasoning moisture content can be reduced to the desired extent. (b) kiln seasoning is quicker than natural seasoning. (c) kiln seasoning is superior to natural seasoning. (d) kiln seasoning needs less stacking place than natural seasoning. 51. In water seasoning (a) timber is placed with thicker end pointing upstream (b) timber is placed with thicker end pointing downstream (c) timber log is placed at right angle to the stream (d) timber may be placed in any direction 52. Most economical method of sawing wood is (a) ordinary sawing (b) quarter sawing (c) tangential sawing (d) radial sawing 53. Sections of more uniform moisture content are obtained by (a) ordinary sawing (b) quarter sawing (c) tangential sawing (d) radial sawing 54. The defect in timber due to broken branch of the tree during the tree growth is (a) knot (b) shake (c) rind gall (d) burl 55. Due to improper cutting of the branches during the growth of the tree, the defect caused in timber is (a) shake (b) rind gall (c) twisted fibre (d) burl DOWNLOADED FROM www.CivilEnggForAll.com 56. Stain appears in wood due to (a) poor ventilation during storage (b) contact with water and chemicals for long time (c) shock when it was young (d) crushing during growth 57. Honeycomb and cracks may occur in timber due to (a) erroneous conversion (b) erroneous seasoning (c) attack by fungi (d) contact with water for a long time 58. Which one of the following is not a preservative of timber (a) solignum salt (b) chemical salt (c) creosote (d) solution of barium hydroxide 59. A thin sheet of wood sliced from a log is called (a) plywood (b) lamin board (c) veneer (d) particle board 60. In a plywood the veneers are placed such that the grains of a layer are (a) at 45° to the grains of a layer below it (b) at 60° to the grains of a layer below it (c) at right angles to the layer below it (d) at 180° to the grains of a layer below it 61. Plywood is identified by (a) volume (b) weight (c) area (d) thickness 62. An assembled product made up of veneers and adhesives is called (a) batten (b) plank (c) board (d) plywood 63. To get plywood of thickness 25 mm, minimum number of plies is (a) 5 (b) 7 (c) 9 DOWNLOADED FROM www.CivilEnggForAll.com (d) 11 64. Particle boards are manufactured by using (a) chips of wood, rice husk and bagasse (b) strips of wood of width 25–80 mm (c) wood pulp (d) none of the above 65. The wood that cannot be attacked by white ants is (a) mahogany (b) rosewood (c) sissoo (d) teak 66. The standard size of bricks as per Indian Standards is (a) 230 × 120 × 80 mm (b) 200 × 100 × 100 mm (c) 190 × 90 × 90 mm (d) 190 × 100 × 100 mm 67. Red colour of brick is due to the presence of (a) lime (b) silica (c) manganese (d) iron oxide 68. Excess of lime in the brick earth makes the bricks (a) brittle and weak (b) crack and warp (c) melt and lose shape (d) improve durability 69. Excess of iron oxide in brick earth makes the bricks (a) stronger (b) darker (c) brittle (d) crack 70. Alumina in brick earth gives the bricks (a) strength (b) colour (c) plasticity (d) resistance to shrinkage 71. Excess of alkalies in the brick earth results into (a) brittleness (b) white patches DOWNLOADED FROM www.CivilEnggForAll.com (c) yellowish colour (d) porous structure 72. Pug mill is used to (a) blend clay (b) tempering (c) weathering clay (d) burning bricks 73. The size of mould used for making bricks compared to size of brick is (a) 10% more (b) 5% more (c) exactly equal (d) 5% less 74. Pallet board is used to (a) make frog in the brick (b) to mount the mould (c) for table moulding of bricks (d) none of the above 75. In stiff mud process of machine moulding, water used for mixing is (a) 8–12% (b) 12–18% (c) 20–24% (d) 30% 76. Gradual drying of moulded bricks is necessary to (a) prevent shrinkage (b) permit shrinkage without cracking (c) permit blending of alumina and silica (d) none of the above 77. The brick is considered dry when the moisture content is (a) 8% (b) 5% (c) 2% (d) zero 78. Hand moulded bricks take ______ days for drying while stiff-mud machine made bricks ______ days. (a) 30, 5 (b) 15, 2 (c) 10, 1 (d) 8, 1/4 79. The indentation markDOWNLOADED left on bricks during FROMthe process of moulding are www.CivilEnggForAll.com (a) pallets (b) fillets (c) marks (d) frog 80. Which one of the following statements is wrong about clamp burning (a) it is cheap (b) does not need skilled labour (c) control on burning process is good (d) burning process is slow 81. Continuous kiln is (a) bull’s trench kiln (b) Hoffman’s kiln (c) tunnel kiln (d) all of the above 82. The minimum strength of brick required for building wall is (a) 7.5 N/mm2 (b) 5.0 N/mm2 (c) 3.5 N/mm2 (d) 2.5 N/mm2 83. To check the size of brick number of bricks to be kept side by side is (a) 30 (b) 20 (c) 10 (d) 5 84. The bricks which may be used to build wall but to be provided with plaster are (a) Ist Class (b) IInd Class (c) IIIrd Class (d) IVth Class 85. The compressive strength of high duty bricks should be more than (a) 40 N/mm2 (b) 20 N/mm2 (c) 5 N/mm2 (d) 3.5 N/mm2 86. Thickness of web of hollow bricks should not be less than (a) 20 mm (b) 16 mm (c) 12 mm (d) 8 mm DOWNLOADED FROM www.CivilEnggForAll.com 87. Compressive strength of paving bricks should not be less than (a) 40 N/mm2 (b) 30 N/mm2 (c) 20 N/mm2 (d) 40 N/mm2 88. Field test for strength of good bricks is to drop it from a height of ______ and they should not break (a) 1.2 m (b) 1.0 m (c) 0.7 m (d) 0.75 m 89. For making stabilized soil brick the soil is stabilized with (a) sand (b) coal (c) cement (d) salt 90. Refractory bricks resist (a) high temperature (b) chemical action (c) action of frost (d) all of the above Clay Products 91. In case of round tiles, under-tiles are used with their narrow ends (a) towards eve (b) towards ridge (c) towards valley (d) in any one fashion 92. Maximum water absorption permitted on class AA type Mangalore tiles is (a) 13% (b) 15% (c) 17% (d) 19% 93. Which of the following statement is wrong? (a) Pan tiles are similar to half round tiles but less curved (b) Pan tiles are weaker than half round tiles (c) Allahabad tiles are interlocking tiles (d) Mangalore tiles are also interlocking tiles 94. The word vitrified means (a) glazed DOWNLOADED FROM www.CivilEnggForAll.com (b) like glass (c) given attractive colour (d) all of the above 95. Terracotta means (a) insulated (b) fit for sanitary services (c) good for ornamental work (d) baked earth 96. Water absorption of vitrified tiles is not more than (a) 0.5% (b) 1.0% (c) 2.0% (d) 5.0% 97. To make terracotta porous, the following is mixed with clay before burning. (a) lime (b) silica (c) sawdust (d) none of the above Ferrous Materials 98. By calcining and smelting iron ores, a crude and impure form of iron obtained is known as (a) cast iron (b) wrought iron (c) steel (d) pig iron 99. The colour of cast iron is (a) grey (b) white (c) both grey and white (d) none of the above 100. The compressive and tensile strength of cast iron are (a) 700 N/m2 and 150 N/mm2 (b) 600 N/mm2 and 400 N/mm2 (c) 415 N/mm2 and 415 N/mm2 (d) 400 N/mm2 and 600 N/mm2. 101. For making spiral staircases, ideal material is (a) pig iron (b) cast iron (c) wrought iron DOWNLOADED FROM www.CivilEnggForAll.com (d) steel 102. Purest form of iron is (a) pig iron (b) cast iron (c) wrought iron (d) steel 103. Carbon content in wrought iron is (a) 0.15% (b) 0.25 to 1.5% (c) 2 to 4% (d) more than 4% 104. The ratio of tensile strength to compressive strength of steel is (a) less than 1 (b) equal to 1 (c) more than 1 (d) nothing can be said definitely 105. Ribs are made on steel wires to increase (a) strength is compression (b) strength is tension (c) bond strength (d) fatigue quality 106. The property of metal enabling it to be drawn into thin wire is known as (a) malleability (b) ductility (c) toughness (d) plasticity 107. The property of the metal enabling it to be transformed it into different shapes by heating is a, b, c, d as per Question No. 106 108. The property of metals due to which it can withstand shock is a, b, c, d as per Question No. 107 Non-ferrous Materials 109. Market form of copper is/are (a) ingots (b) sheets (c) tubes (d) all of the above 110. The ore from which aluminium is extracted economically is (a) kaolin (b) kryolite DOWNLOADED FROM www.CivilEnggForAll.com (c) corundum (d) bauxite 111. Specific gravity of aluminium is (a) 1.5 (b) 2.7 (c) 3.5 (d) 4.2 112. Zinc is (a) an alloy of aluminium and copper (b) an alloy of aluminium and chrome (c) an alloy of copper and chrome (d) a metal 113. The heaviest metal is (a) steel (b) lead (c) tin (d) cast iron 114. Which of the following metal is poisonous? (a) aluminium (b) tin (c) lead (d) copper Alloys 115. Duralumin is an alloy of (a) aluminium and copper (b) aluminium, copper, nickel and magnesium (c) aluminium and zinc (d) aluminium and tin 116. Which of the following is a variety of aluminium alloy (a) duralumin (b) aldural (c) Y-alloy (d) all the above 117. Aluminium alloys used in building bodies of aeroplane are (a) duralumin and aldural (b) aldural and aluminium bronze (c) aluminium bronze and Y-alloy (d) Y-alloy and duralumin 118. Which one of the following is not a variety DOWNLOADED FROMofwww.CivilEnggForAll.com brass (a) white brass (b) yellow brass (c) red brass (d) brown brass 119. Bronze is an alloy of (a) aluminium and copper (b) copper and zinc (c) copper and tin (d) none of the above 120. The constituents of stainless steel are (a) steel, chromium and nickel (b) steel and nickel (c) steel and manganese (d) steel and molybdenum 121. Quick lime is (a) calcium carbonate (b) calcium oxide (c) calcium hydroxide (d) none of the above 122. When fat lime is slaked, its volume (a) decreases to 50% (b) remains same (c) increases by 2 to 2.5 times (d) increases by 4 times. 123. Which one of the following statement is correct? (a) Fat lime contains hardly 5% clay (b) Hydraulic lime contains 5.30% clay (c) Poor lime contains more than 30% clay (d) All the above 124. For plastering work lime used is (a) quicklime (b) fat lime (c) hydraulic lime (d) poor lime 125. Hydraulic lime is obtained by (a) burning kankar (b) calcination of limestone (c) slaking quicklime (d) calcination of pureDOWNLOADED clay FROM www.CivilEnggForAll.com 126. The process of adding water to quicklime in order to convert it into hydrated lime is known as (a) quenching (b) hydration (c) calcination (d) slaking 127. The commonly used lime for whitewashing is (a) hydraulic lime (b) lean lime (c) fat lime (d) quicklime 128. Quicklime on reaction with water gives (a) calcium oxide (b) calcium carbonate (c) calcium hydroxide (d) none of the above 129. The lime which has property of setting in water is known as (a) fat lime (b) hydraulic lime (c) quicklime (d) magnesium lime 130. The fuel generally used for burning lime stone is (a) firewood (b) charcoal (c) coal (d) any one of these 131. Fat lime (a) slakes rapidly with considerable evolution of heat (b) has high plasticity (c) takes longer to develop adequate strength (d) all of the above 132. The main constituent which imparts hydraulicity to hydraulic lime is (a) calcium oxide (b) silica (c) clay (d) water 133. The constituent responsible for setting of hydraulic lime under water is (a) calcium oxide (b) clay (c) silica DOWNLOADED FROM www.CivilEnggForAll.com (d) carbon dioxide 134. The process of heating limestone to redness is termed as (a) hydration (b) carbonation (c) oxidation (d) calcination 135. The major constituent of cement is (a) lime (b) silica (c) alumina (d) iron oxide 136. The constituent which imparts strength to cement is (a) lime (b) silica (c) alumina (d) magnesia 137. The constituent which imparts colour to cement is (a) lime (b) silica (c) alumina (d) iron oxide 138. Rotary kiln used in manufacturing cement rotates at a speed of (a) 1–3 rpm (b) 10–12 rpm (c) 18–22 rpm (d) more than 25 rpm 139. The clinker is formed at a temperature of (a) 500–600° C (b) 900–1000° C (c) 1100–1300° C (d) 1400–1500° C 140. The amount of gypsum added in the manufacture of cement is (a) 0.1–0.5% (b) 0.5–1% (c) 1–3.0% (d) 3–4% 141. Gypsum is added in the manufacture of Portland cement to (a) reduce setting time of cement (b) increase setting time of cement DOWNLOADED FROM www.CivilEnggForAll.com (c) to enhance the strength of cement (d) to decrease grinding time 142. Gypsum is added during the manufacture of cement (a) while mixing the raw materials (b) during burning in the kiln (c) at the beginning of grinding the clinker (d) after grinding the clinker 143. Specific surface of cement is (a) measure of fineness (b) measure of volume of cement (c) measure of smoothness of cement (d) none of the above 144. Specific surface of cement should not be less than (a) 100 cm2/gm (b) 1500 cm2/gm (c) 2000 cm2/gm (d) 2250 cm2/gm 145. Specification for setting time of ordinary Portland cement are: Initial setting lime Final setting lime (a) > 30 min > 600 min (b) > 30 min < 600 min (c) < 30 min < 600 min (d) < 30 min > 600 min 146. The compound responsible for initial setting of cement is (a) Tricalcium aluminate (b) Tricalcium silicate (c) Dicalcium silicate (d) Tetra alumino ferrite 147. The compound that hydrates early and is responsible for gain in strength in 28 days is a, b, c, d as in Question No. 146. 148. The compound that hydrates slowly and responsible for gain of strength over a period of 1 year is a, b, c, d as per Question No. 146. 149. Unsoundness in cement is due to (a) free lime (b) free magnesia (c) insufficient grinding DOWNLOADED FROM www.CivilEnggForAll.com (d) all the above 150. Le Chatelier apparatus is used for testing cement for its (a) strength (b) setting time (c) fineness (d) soundness 151. At the end of the test on cement, increase in the distance between the two indicators of Le Chatelier apparatus should not be more than (a) 5 mm (b) 10 mm (c) 15 mm (d) 20 mm 152. 43-grade cement has a strength of 43 N/mm2 at the age of (a) 3 days (b) 7 days (c) 28 days (d) 1 year 153. Vicat apparatus is used for determining (a) initial setting time of cement (b) final setting time of cement (c) normal consistency of cement (d) all of these 154. Normal consistency of cement is about (a) 7% (b) 14% (c) 21% (d) 28% 155. Addition of Pozzolana to Portland cement causes (a) increase in heat of hydration (b) increase in strength (c) increase in water tightness (d) all the above 156. Blast furnace slag cement is (a) durable (b) gains strength slowly (c) cheap (d) all the above 157. High alumina cement is (a) more resistant to sulphate attack DOWNLOADED FROM www.CivilEnggForAll.com (b) more resistant to acid attack (c) gains almost full strength within 24 hours after adding water (d) all the above 158. Which one of the following is not correct statement about fly ash blended cement? (a) They have superior resistance to weathering action. (b) They gain strength fast. (c) Ultimate strength is same as OPC. (d) All the above. 159. To prevent setting of cement during storage the material added to cement during grinding is (a) acidol (b) oleic acid (c) oxidized petroleum (d) any of the above 160. Rapid hardening cement is produced by (a) increasing the lime content (b) burning it at high temperature (c) grinding to a finer size (d) all the above 161. Which one of the following is the correct statement about quick setting cement? Initial setting lime Final setting lime (a) < 5 min < 30 min (b) < 5 min > 30 min (c) > 5 min < 30 min (d) > 5 min < 30 min 162. Which statement given below is wrong? The pigment used to produce coloured cement (a) cobalt oxide to get blue colour. (b) chloride oxide to get green colour. (c) manganese oxide to get brown colour. (d) aluminium oxide to get white colour. 163. Identify the correct statement given below: The natural Pozzolanic material is/are (a) clay (b) shale (c) volcanic sand (d) all the above 164. Which one of the following is not a Pozzolanic material? (a) fly ash (b) rice husk ash DOWNLOADED FROM www.CivilEnggForAll.com (c) gypsum (d) blast furnace slag 165. Silica fumes have found their use in (a) pumped concrete (b) high strength concrete (c) shutcrete application (d) all the above 166. For testing compressive strength of cement, the size of cubes used is (a) 50 mm (b) 70.6 mm (c) 100 mm (d) 150 mm 167. The sand in mortar (a) prevents shrinkage (b) spreads mortar (c) allows carbon dioxide from the atmosphere to penetrate deeply (d) all the above 168. An aggregate is called fine aggregate if it is completely passes through (a) 150 micron sieve (b) 300 micron sieve (c) 600 micron sieve (d) 4.75 mm sieve 169. The aggregate is called coarse aggregate if it is completely retained on (a) 20 mm sieve (b) 12 mm sieve (c) 8 mm sieve (d) 4.75 mm sieve 170. Due to bulking of sand, increase in volume is as high as (a) 5% (b) 15% (c) 25% (d) 30–40% 171. Maximum increase in the bulk of sand is at the moisture content (a) 2 – 4% (b) 4 – 6% (c) 8 – 10% (d) 12 – 15% 172. Bulking of sand is due to (a) water films DOWNLOADED FROM www.CivilEnggForAll.com (b) swelling of sand (c) added mass of water (d) none of the above 173. Which one of the following is not a desirable property of sand? (a) It should be chemically active. (b) It should contain sharp, angular grains. (c) It should be hard. (d) It should be well graded. 174. The increase in volume of sand when water is added is known as (a) segregation (b) bleeding (c) bulking (d) honeycombing 175. The cement to dry sand proportion recommended for masonry work is (a) 1 : 3 (b) 1 : 6 (c) 1 : 10 (d) 1 : 12 176. The cement to dry sand proportion recommended for plastering external wall is (a) 1 : 3 – 1 : 4 (b) 1 : 6 (c) 1 : 8 (d) 1 : 10 177. The cement to dry sand proportion recommended for plastering concrete surface is (a) 1 : 3 (b) 1 : 6 (c) 1 : 8 (d) 1 : 10 178. The cement to dry sand proportion for pointing work is (a) 1 : 2 (b) 1 : 4 (c) 1 : 6 (d) 1 : 8 179. The inert material to be used for making lime mortar is (a) sand (b) surkhi (c) cinder (d) any of the above 180. Gauged cement mortar consists of FROM www.CivilEnggForAll.com DOWNLOADED (a) cement and sand (b) cement, surkhi, sand (c) cement, lime, sand (d) cement, cinder, sand 181. Briquettes are the specimen of mortar used for finding (a) compressive strength (b) tensile strength (c) flexural strength (d) shear strength 182. Fineness modulus is (a) the ratio of fine aggregates to coarse aggregate. (b) the ratio of fine aggregates to total aggregate. (c) an index which gives the mean size of the aggregates used in a mix. (d) none of the above. 183. Which one of the following statement is wrong? (a) Lime concrete is used as base course for foundations. (b) Lime concrete is used as base course to ground floor. (c) Lime concrete is used to make roof waterproof. (d) It is used for R.C.C structural elements. 184. Which one of the following statement is wrong? In the absence of mix design, the ingredients of concrete are proportioned as (a) 1 : 1 : 2 – mass concrete work (b) 1 : 1 : 3 – water tanks (c) 1 : 2 : 4 – slabs, beams (d) 1 : 3 : 6 – sills of windows 185. M : 20 concrete means (a) 1 : 2 : 4 concrete (b) concrete with a strength of 20 kg/cm2 after 28 days (c) concrete with a strength of 20 N/mm2 after 7 days (d) concrete with a strength of 20 N/mm2 after 28 days 186. In order to achieve required workability and good strength at the same time, water cement ratio, in case of machine mixing is (a) 0.3 – 0.4 (b) 0.4 – 0.5 (c) 0.5 – 0.6 (d) none of the above 187. In case of hand mixing in order to achieve good workability and good strength at the same time is DOWNLOADED FROM www.CivilEnggForAll.com (a) 0.3 – 0.4 (b) 0.4 – 0.5 (c) 0.5 – 0.6 (d) none of the above 188. The weight and volume of one bag of cement respectively are (a) 50 kg and 35 litres (b) 60 kg and 30 litres (c) 50 kg and 30 litres (d) 60 kg and 35 litres 189. If the water cement ratio to be used is 0.5, then water to be added to one bag of cement is (a) 30 kg (b) 25 kg (c) 20 kg (d) 18 kg 190. In machine mixing of concrete, the drum is rotated to make about (a) 35 rotations (b) 50 rotations (c) 65 rotations (d) 80 rotations 191. For transporting concrete which one of the following is not used? (a) pans (b) chutes (c) belt conveyor (d) tractor 192. Concrete should not be placed by dropping at a height more than (a) 400 mm (b) 600 mm (c) 800 mm (d) 1000 mm 193. Compaction of concrete is to (a) remove entrapped air (b) spread cement paste uniformly (c) get level surface at top (d) all of the above 194. Curing of concrete is the process of (a) keeping the surrounding cool (b) ponding the water on the surface (c) covering the surface with wet gunny bags (d) maintaining satisfactory moisture andFROM DOWNLOADED temperature for a specific time www.CivilEnggForAll.com 195. In precast industries, best method of curing is (a) ponding (b) covering with wet gunny bags (c) spraying water (d) steam curing 196. Curing compound mainly consists of (a) calcium hydroxide (b) calcium oxide (c) chlorinated rubber (d) calcium nitrate 197. Workability of concrete depends on (a) water content (b) aggregate shape and size (c) mix proportion (d) all the above 198. Which one of the following yields more workable concrete? (a) Bigger size aggregates with rounded shape. (b) Bigger size aggregates with angular shape. (c) Smaller size aggregates with rounded shape. (d) Smaller size aggregates with angular shape. 199. Which one of the following mix has higher workability? (a) Well graded aggregate with richer mix. (b) Well graded aggregate with poorer mix. (c) Uniform grade aggregate with rich mix. (d) Uniform grade aggregate with poor mix. 200. Workability of concrete is determined by (a) slump test (b) compaction factor test (c) Vee-Bee test (d) all the above 201. Slump required for concreting lightly reinforced sections without vibration is (a) up to 25 mm (b) 25 – 75 mm (c) 25 – 100 mm (d) more than 100 mm 202. Slump required for concreting heavily reinforced sections without vibration is (a) up to 25 mm (b) 25 – 50 mm (c) 50 – 75 mm DOWNLOADED FROM www.CivilEnggForAll.com (d) 75 – 125 mm 203. For concreting heavily reinforced sections without vibrations, compaction factor should be (a) 0.75 – 0.80 (b) 0.80 – 0.85 (c) 0.85 – 0.92 (d) more than 0.92 204. Vee-Bee consistometer test is suitable for finding workability of (a) rich concrete (b) lean concrete (c) stiff concrete (d) all the above 205. Segregation is due to (a) lack of sufficient quantity of fine aggregates (b) dropping concrete from a greater height (c) over vibration (d) all the above 206. Bleeding of freshly laid concrete means (a) segregation of concrete (b) voids appearing on the surface (c) appearance of water along with cement paste on the surface (d) all the above 207. The ratio of strength of concrete after 1 year to that at 28 days is (a) 0.9 (b) 1.0 (c) 1.1 (d) 1.2 208. On cylindrical specimen, split test is conducted to determine (a) compressive strength of concrete (b) tensile strength (c) flexural strength (d) all the above 209. Indian Standards specifications for estimating tensile strength and modulus of elasticity of concrete, if characteristic strength fck is known, are respectively (a) 0.75 and 7000 (b) 0.7 and 5000 (c) 0.75 fck and 7000 fck (d) 0.7 fck and 5000 fck 210. Creep is permanentDOWNLOADED change in dimensions FROM duewww.CivilEnggForAll.com to (a) temperature variation (b) whethering action caused by moisture in the air (c) sustained load (d) all the above 211. Creep coefficient of concrete depends upon (a) stress in concrete (b) the age of concrete at the time of loading (c) duration of loading (d) all the above 212. Coefficient of thermal expansion is highest in (a) quartzite (b) sandstone (c) granite (d) basalt 213. Which one of the following is not workability enhancing agent? (a) air entraining agents (b) plasticizer (c) super plasticizer (d) silica fume 214. Which one of the following is not a construction chemical? (a) silica fume (b) bonding agents (c) curing compound (d) none of the above 215. Which one of the following is not a light-weight concrete? (a) aerated concrete (b) no fine concrete (c) polymer concrete (d) foamed slag concrete 216. Concrete mix design is intended to (a) achieve specified characteristic strength (b) achieve required workability (c) achieve impermeability (d) both (a) and (b) 217. Minimum cement content for moderate exposure with normal weight aggregates of size 20 mm in concrete is (a) 280 kg/m3 (b) 300 kg/m3 (c) 320 kg/m3 DOWNLOADED FROM www.CivilEnggForAll.com (d) 340 kg/m3 218. Fibre reinforced concrete is used in (a) wearing coat of roads (b) pipes, manhole covers (c) door and window frames (d) all the above 219. Which one of the following is not correct about the use of ferrocement? (a) for doors and window shutters (b) domestic water tanks (c) furnitures (d) beam and columns 220. The ingredient of paint which gives it the binding property and form opaque coating is (a) base (b) vehicle (c) solvent (d) filler 221. The ingredient of paint that holds the ingredients in liquid suspension and allows them to be applied on the surface is: (a) base (b) vehicle (c) solvent (d) filler 222. The ingredient of paint that increases coverage area and makes application easy is (a) base (b) vehicle (c) solvent (d) filler 223. The ingredient of paint that reduces the cost and increases durability is (a) base (b) vehicle (c) solvent (d) filler 224. The cheap ingredient of a paint is (a) base (b) vehicle (c) filler (d) solvent 225. The presence of dampness while applying the primer affects the life of (a) oil paint DOWNLOADED FROM www.CivilEnggForAll.com (b) enamel paint (c) aluminium paint (d) plastic paint 226. Commonly used base for paint is (a) iron oxide (b) red lead (c) titanium white (d) any one of the above 227. Commonly used vehicle in paint is (a) linseed oil (b) poppy oil (c) nut oil (d) any one of the above 228. Commonly used solvent in paint is (a) white lead (b) turpentine (c) linseed oil (d) any of the above 229. Commonly used inert extenders used in paint is (a) magnesia (b) alumina (c) charcoal (d) any one of the above 230. Enamel paint is prepared by adding white lead or zinc to (a) varnish (b) polysterene (c) spirit (d) to any one of the above 231. The surface of which paint can be cleaned by washing with water? (a) oil paint (b) enamel paint (c) emulsion paint (d) bituminous paint 232. The paint which shines and is visible even in darkness is (a) synthetic rubber paint (b) cellulose paint (c) aluminium paint (d) emulsion paint 233. Which paint is ideally suited to get damp-proof DOWNLOADED surface? FROM www.CivilEnggForAll.com (a) plastic paint (b) asbestos paint (c) synthetic rubber paint (d) aluminium rubber paint 234. The base material for distemper is (a) iron oxide (b) lithopone (c) chalk (d) lime 235. The solvent used in cement paint is (a) spirit (b) water (c) turpentine (d) naptha 236. Paint with white lead base is suitable for painting (a) concrete surfaces (b) walls (c) woodwork (d) iron work 237. Painting work is generally specified by (a) weight of the paint used (b) volume of the paint used (c) labour used for painting (d) area of the painted surface. 238. The small areas on painted surface enclosed by hair line cracks are known as (a) blistering (b) crazing (c) wrinkling (d) chalking 239. Varnish is generally made of (a) spirit (b) solvent (c) resin (d) both (b) and (c) 240. In the fractional distillation of crude oil the components of crude which do not evaporate is (a) kerosene (b) spirit (c) bitumen (d) fuel oil DOWNLOADED FROM www.CivilEnggForAll.com 241. Select correct option about bitumen (a) Its components are carbon, hydrogen and oxygen. (b) It becomes soft at 30° to 100° C. (c) It is susceptible to oxidation, forming blisters and cracks. (d) All the above. 242. Cut back bitumen is produced by adding (a) gasolin (b) kerosene (c) high boiling point light oil (d) any of the above 243. Asphalt is obtained by adding (a) kerosene (b) gasolin (c) sand (d) any of the above 244. Tar is obtained by destructive distillation of (a) coal (b) wood (c) mineral tar (d) any one of the above 245. At 30°C asphalt is available in the state of (a) solid or semisolid (b) solid (c) viscous (d) any of the above 246. Adhesive power is highest in case of (a) asphalt (b) bitumen (c) cold tar (d) none of the above 247. Main constituent of glass is (a) alumina (b) silica (c) acrylic (d) none of the above 248. Molten glass can be fabricated by (a) blowing (b) drawing (c) casting DOWNLOADED FROM www.CivilEnggForAll.com (d) any of the above 249. Annealing the glass is the process of (a) blowing and drawing (b) drawing and casting (c) heating and slow cooling (d) any of the above 250. Tempering the glass is the process of (a) giving requisite degree of hardness (b) making it impervious to light (c) a method of fabrication (d) none of the above 251. The glass used as windowpanes and laboratory tables is (a) soda lime glass (b) potash lime glass (c) potash lead glass (d) common glass 252. The glass used for making artificial gem is (a) soda lime glass (b) potash lime glass (c) potash lime glass (d) coloured glass 253. Wired glass is used for (a) telephone communication (b) medicine bottles (c) fire resistant doors (d) artificial gems 254. Bulletproof glass has (a) a number of layers all of same thickness (b) outer layers thinner than inner layers (c) outer layers thicker than inner layers (d) inner layers with steel wires 255. Shielding glass contains (a) steel wires (b) fibre glass (c) lead oxide (d) chrome 256. Structured glass is (a) usually coloured (b) mirrored DOWNLOADED FROM www.CivilEnggForAll.com (c) heat resistant (d) all the above 257. Polymerization is the process of (a) combine monomers to form a large chain-like molecule (b) combine monomers to form a small chain-like molecule (c) Break a polymer into a number of small monomers (d) Break a polymer to form into a number of long monomers 258. Phenol formaldehyde is produced by (a) addition polymerization (b) condensation polymerization (c) copolymerization (d) any of the above 259. Which is wrong statement about thermosetting plastics? (a) Undergo chemical changes at 127–177°C. (b) Reheating will soften them. (c) If heated to 340° C charring takes place. (d) Soluble in alcohol. 260. Which one of the following is correct statement about thermo plastics? (a) Soften on heating and hardens on cooling. (b) The process of hardening and softening may be repeated any number of times. (c) Scrap obtained from old article can be reused by softening and reshaping. (d) All the above. 261. Fibre reinforced plastics are manufactured by reinforcing plastic with (a) paper (b) asbestos (c) glass (d) any of the above 262. Cork is obtained from (a) bark of oak tree (b) destructive distillation of wood (c) mines (d) any of the above sources 263. Vulcanization of rubber is to (a) purify rubber (b) toughen rubber (c) make it soft (d) all the above 264. Gypsum boards are manufactured by mixing gypsum with (a) tar DOWNLOADED FROM www.CivilEnggForAll.com (b) bitumin (c) asphalt (d) rubber 265. Turpentine is a natural material obtained from (a) oak trees (b) pine trees (c) mines (d) any of the above 266. Which one is the correct statement about geosynthetics? (a) They are fabrics of nylon. (b) They last long even if they are buried under soil. (c) They are not affected by water. (d) All the above. II. Match List I with List II and select the correct answer code given below the List 267. List I Class List II Example A. Volcanic rocks 1 Gneiss B. Hyperbyssal rocks 2 Granite C. Plutonic rocks 3 Quartz D. Metamorphic rocks 4 Basalt Codes: A B C D (a) 3 2 4 1 (b) 1 3 2 4 (c) 4 3 2 1 (d) 2 4 3 1 268. List I List II Type of stone Strength A. Trap 1 104 – 140 N/mm2 B. Marble 2 300 – 350 N/mm2 C. Granite 3 70 – 210 N/mm2 D. Sandstone 4 65 – 70 N/mm2 DOWNLOADED FROM www.CivilEnggForAll.com Code (a) A– 3 B– 2 C–1 D–4 (b) A– 2 B– 1 C–4 D–3 (c) A– 1 B– 2 C–4 D–3 (d) A– 2 B– 3 C–1 D–4 269. List I List II Stone Mohs hardness number A. Gypsum 1 2 B. Calcite 2 3 C. Quartz 3 7 D. Corundum 4 9 Codes (a) A– 1 B– 2 C–4 D–3 (b) A– 2 B– 1 C–4 D–3 (c) A– 1 B– 2 C–3 D–4 (d) A– 2 B– 1 C–4 D–3 270. List I List II Type of wood Used for A. Jack 1. Agricultural implements B. Deodar 2. Boat construction C. Babul 3. Railway sleepers D. Benteak 4. Musical instruments Codes: (a)

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