CEIR11 Basic Civil Engineering Lecture Notes PDF

CEIR11 Basic Civil Engineering Dr. Lekshmi Mohan V Assistant Professor Department of Civil Engineering National Institute of Technology, Tiruchirappalli Email: [email protected]  Tests on Cement 10/1/2024 CEIR11 Basics of Civil Enginee...

CEIR11 Basic Civil Engineering Dr. Lekshmi Mohan V Assistant Professor Department of Civil Engineering National Institute of Technology, Tiruchirappalli Email: [email protected]  Tests on Cement 10/1/2024 CEIR11 Basics of Civil Engineering 2 Fineness of Cement by Blaine air permeability method Fineness: It is the degree of grinding of cement The rate of reaction depends upon the fineness of cement For accurate measurement, it is measured by surface area, air permeability method Normal value - 200 to 300 m2/kg of cement 10/1/2024 CEIR11 Basics of Civil Engineering 3 Fineness of Cement – by standard sieve method 100 gm of cement is weighed accurately, placed on IS: sieve No. 9 (90 micron) and sieved The residue left is weighed This shall not exceed 10% by weight of the sample This is estimated in terms of the specific surface, i.e., the surface area per unit weight 10/1/2024 CEIR11 Basics of Civil Engineering 4 Setting Time: Initial & Final Vicat’s apparatus Setting of cement is the phenomenon by virtue of which the green cement changes into hard mass The time between water is added in cement and initial setting takes place is known as Initial Setting Time Initial setting is a stage in the process of hardening after which any crack that may appear will not reunite and the completion of this process is, known as final setting time Cement should not loose its plasticity till the various operations of mixing, transporting and placing are For initial setting complete. Hence this time is generally kept not less than 30 minutes and the final setting is not more than 10 hours For final setting 10/1/2024 CEIR11 Basics of Civil Engineering 5 Compressive Strength The quality of concrete and cement is always judged by strength and that is only by compressive strength because cement is weak in tension and for it steel reinforcement is always provided For this purpose cement and standard sand are mixed in the ratio of 1:3 Grades of cement : 33, 43, 53 - (Strength (in MPa) on 28th day of curing) 10/1/2024 CEIR11 Basics of Civil Engineering 6 Soundness Free lime and magnesia present in cement makes the cement unsound by increasing the volume after setting. Expansion should not be more than 10 mm More lime (or calcium hydroxide) leads to cracks in concrete It is generally measured by Le-Chatelier method 10/1/2024 CEIR11 Basics of Civil Engineering 7  Concrete 10/1/2024 CEIR11 Basics of Civil Engineering 8 Concrete Concrete is the most versatile material for all types of construction works and has been used for innumerable construction works, either as plain concrete or as reinforced cement concrete or as precast concrete, or prestressed concrete or in many other forms. The various constituents of concrete are cement, water, fine aggregate, and coarse, aggregates. 10/1/2024 CEIR11 Basics of Civil Engineering 9 Role Aggregate: (Coarse and Fine) These are the inert or chemically inactive materials which form the bulk of cement concrete. These aggregates are bound together by means of cement. The aggregates are classified into two categories, Fine and coarse. The material which is passed through 4.75mm size sieve is termed as fine aggregate. Usually natural river sand, issued as a fine aggregate. The material which is retained on 4.75 mm size sieve termed as a coarse aggregate. Broken stone is generally used as a coarse aggregate. Water Water which is used for making concrete should be clean and free from harmful impurities such as oil, alkali, acid etc. In general water which is fit for drinking should be used for making concrete. 10/1/2024 CEIR11 Basics of Civil Engineering 10 Grades of Concrete Concrete as per IS 456:2000 is classified into three groups as ordinary concrete, Standard concrete and High strength concrete. M10, M15 and M20 are ordinary concrete M25, M30, M35, M40, M45, M50 and M55 are grouped as Standard concrete M60, M70, M75 and M80 are grouped under High strength concrete. The letter ‘M’ refers to the mix and the number indicates the specified compressive strength of that mix at 28 days expressed in or Mega Pascal (MPa) or N/mm2. M 5 - 1:5:10 (Cement : Fine aggregate : Coarse aggregate) M 7.5- 1:4:8 M 10 - 1:3:6 M 15 - 1:2:4 M 20 - 1:1.5:3 M 25 - 1:1:2 10/1/2024 CEIR11 Basics of Civil Engineering 11 Gain of strength with age The concrete develops strength with continued hydration. The rate of gain of strength is faster to start with and the rate gets reduced with age. It is customary to assume the 28 days strength as the full strength of concrete. The variation of strength with age is given below Age of curing (Days) Approx. Strength achieved 3 1/3rd of target strength 7 2/3rd 28 90 % 10/1/2024 CEIR11 Basics of Civil Engineering 12 Strength of Concrete Strength of concrete is its resistance to rupture. It may be measured in number of ways, such as strength in compression, in tension, in shear or in flexure. The compressive strength of concrete is generally determined by testing cubes or cylinders made in laboratory or field. The size of the mould should be 150 mm x 150 mm x 150 mm. Based on the compressive strength, the concrete is graded. The strength of the concrete is mainly depend on the following factors: Quality of materials and grading of the aggregates Water cement ratio Cement content Age of concrete and Methods of mixing, placing, compacting and curing. 10/1/2024 CEIR11 Basics of Civil Engineering 13 Workability of concrete The workability of concrete indicates the ease with which it can be mixed, placed and compacted. Slump test is the most commonly used method of measuring workability of concrete which can be employed either in the laboratory or at site of work. 10/1/2024 CEIR11 Basics of Civil Engineering 14 Water Cement Ratio The strength of concrete depends upon the quantity and quality of its ingredients i.e. cement, aggregate and water. General assumption is that strength of concrete directly depends up on the quantity of cement. If cement is more, strength will be more but this assumption is not correct because strength of concrete also depends upon water cement ratio. 10/1/2024 CEIR11 Basics of Civil Engineering 15 Operations in Concreting Storing of material (Cement, aggregate) Batching of material (By volume, by weight) Mixing of concrete (By hand, by machine) Transportation of concrete. Placing of concrete. Curing of concrete 10/1/2024 CEIR11 Basics of Civil Engineering 16 Storing of Material Cement: It is a fine powder and also hygroscopic in nature i.e. it absorbs moisture from air or free water and starts setting. Hence the warehouses constructed for its storage must fulfill the basic requirements. Cement stored for long time should be checked before its use. Aggregates: It is essential that aggregate should be free from deleterious materials, organic matters such as tree leaves, vegetable wastes, animal refuse etc. It should have uniform moisture content and proper grading of aggregates. 10/1/2024 CEIR11 Basics of Civil Engineering 17 Batching of Materials Batching means measurement of ingredients of concrete for proper mixing. Normally such a quantity is mixed in one batch, which can be transported, placed and compacted with in time i.e. before initial set takes place. Batching is of two types Volume Batching Weigh Batching Measurement of Cement: Cement is always measured by weight. A batch of concrete should always consume full number of bags. For this purpose weight, of cement bag is taken as 50 kg. Measurement of Water: Water is generally measured by volume. Measurement of Aggregate by Volume: For these purpose generally wooden boxes of capacity equivalent or part of one cement bag i.e. 35 liters are used. These boxes are known as Petties or Farmas or Gauge Box. 10/1/2024 CEIR11 Basics of Civil Engineering 18 Volume batching 10/1/2024 CEIR11 Basics of Civil Engineering 19 Transportation of concrete As the initial setting time of cement is generally 30 minutes, hence mixing, transportation, placing and compaction should be completed with in this time. In no case this time should not exceed one hour after initial setting time. 10/1/2024 CEIR11 Basics of Civil Engineering 20 Placing of Concrete As for as possible concrete should be placed in single thickness. In case of deep sections, concrete should be placed in successive horizontal layers and proper care should be taken to develop enough bond between successive layers. 10/1/2024 CEIR11 Basics of Civil Engineering 21  Curing of Concrete Concrete surfaces are kept wet for a certain period after placing the concrete. The period of curing depends on the type of cement and nature of work. For ordinary Portland cement, the curing period is 7 to 14 days. If rapid hardening cement is used, curing period can be considerably reduced. It can be done by spraying and ponding of water or covering the concrete with moist earth, sand, or wet gunny bags 10/1/2024 CEIR11 Basics of Civil Engineering 22 Steel Steel is probably the most versatile commonly used structural material. Steel is used to a large extent in modern multi- storied buildings. Steel is used as reinforcing bars/wires for concrete since concrete is weak in tension. Structural steel is available in various forms and shapes and it is being used for various structural components. 10/1/2024 CEIR11 Basics of Civil Engineering 23 How is steel manufactured? 2O 2 + 4 H 2 O + 4F e → 4 Fe (O H )2 4 Fe (O H )2 + O 2 + 2 H 2 O → 4Fe ( OH )3 Iron Ore Rolling/ other manufacturing (Fe2O3) Blast Furnace Molten material processes 10/1/2024 CEIR11 Basics of Civil Engineering 24 Steel Alloy of iron and carbon Steel is obtained by decreasing the carbon content by controlled oxidation. The excess oxygen is removed by incorporating manganese and silicon. When elements other than Mn and Si are present, it is called alloy steel. When certain elements, such as Cr and Ni are added, it is called stainless steel. 10/1/2024 CEIR11 Basics of Civil Engineering 25 Applications of Steel As Steel has high tensile strength, it was used in: Construction of buildings Infrastructure Tools Ships Automobiles Machines & appliances Weapons 10/1/2024 CEIR11 Basics of Civil Engineering 26 Different Types of Steels Based on Carbon Content: Low Carbon Steel 0% to 0.25 % of Carbon, Outstanding ductility and toughness. Good machinability and weldability, high formability, toughness, high ductility etc. Medium Carbon Steel From 0.25% to 0.55% C, Stronger than low – carbon steel but less tough than it, Railway wheels & tracks, gears etc. High Carbon Steel From 0.55% up to 2.1 % C, Hard, strongest, and least ductile compared to Low carbon steels. Knives, hack saw blades, chisels, hammers, drills, dies, machine tool cutters, punches, etc. 10/1/2024 CEIR11 Basics of Civil Engineering 27 Different Types of Steels Based on the Method of manufacture of Steels Bessemer steel Method The principle of Bessemer Converter is the removal of impurities from the iron by oxidation and the air is being blown through the molten iron. The furnace is made of steel with fire clay bricks to resist heat. The impurities manganese(Mn) and Silicon(Si) are converted into their respective oxides and that can be expelled out. Electric Arc Furnace Method It is an extremely hot enclosed region, where heat is produced employing electrodes for melting certain materials such as steel (scrap) without changing the electrochemical properties of the material(metal). The electric arc produced between the electrodes and the metal is used for melting the metal(scrap). 10/1/2024 CEIR11 Basics of Civil Engineering 28 Different Types of Steels Based on properties of some other types of Steels Shock-resisting Steel: These steels can resist fatigue loads and shock loads. High-strength Steel: Applied where Low weight and high strength are required. Tool Steel: These are mainly used for making Tools and Dies for cutting, forming and forging metals in their hot or cold conditions. Spring Steels: Used for making Coiled and Leaf springs. Heat Resistant Steels: These steels can resist corrosion, oxidation and creep at higher working temperatures. 10/1/2024 CEIR11 Basics of Civil Engineering 29 Different Types of Steels Based on Effect of Alloying elements on Steel Cobalt/Molybdenum: It has high servicing temperature or high temperature sustainability. Chromium: It improves Corrosion resistance and Abrasion resistance. Vanadium: It exhibits high temperature resistance, hardness and strength. Aluminum: It improves fracture toughness and acts as deoxidant. Phosporous: It increase strength, hardness and improves machinability. Sulphur: It improves machinability. Silicon: It exhibits high hardenability. Magnesium: It improves toughness and machinability. Manganese: Wear resistance and hardness is high. 10/1/2024 CEIR11 Basics of Civil Engineering 30 Lecture Objectives To introduce various types of buildings, factors influencing site selection of buildings 10/1/2024 CEIR11 Basics of Civil Engineering 31 Types of Buildings Residential Buildings ❖ The buildings in which sleeping accommodation is provided for normal residential purposes with or without cooking and dining facilities. ❖ Eg : houses, flats, hostels, restaurants, residential hotels. 10/1/2024 CEIR11 Basics of Civil Engineering 32 Types of Buildings Educational Buildings ❖ Buildings for education purposes. ❖ Eg: Schools, colleges etc. Institutional Buildings ❖ Buildings constructed by the government, semi- government organizations or registered trusts for specific purposes. ❖ These buildings provide sleeping accommodation for the occupants. ❖ Eg: hospitals, jails, prisons and mental asylums. 10/1/2024 CEIR11 Basics of Civil Engineering 33 Types of Buildings Assembly Buildings ❖ These are the buildings where groups of the people meet or gather. ❖ Eg: Theatre, assembly halls, club house, places of worships, auditoriums, museums. Business Buildings ❖ These buildings are used for transaction of business, for keeping of accounts, records and similar purposes. ❖ Eg: Offices, banks, court houses, libraries. 10/1/2024 CEIR11 Basics of Civil Engineering 34 Types of Buildings Mercantile Buildings ❖ The entire building or a part of it is used for housing shops or showrooms where display and sale of goods or merchandise is carried out. ❖ Eg: shops, stores, mall, market etc. Industrial Buildings ❖ These are the buildings in which products or materials of all kind and properties are fabricated, assembled and processed. ❖ Example: Factories, gas plants, dairy plants, mills 10/1/2024 CEIR11 Basics of Civil Engineering 35 Types of Buildings Storage Buildings ❖ The buildings are used for storage of commodities, goods, merchandise etc. ❖ Eg: Warehouses, cold storages, grain storage units, barns, stables, hangars Hazardous Buildings ❖ These buildings are used for storage, handling, manufacture or processing of highly combustible explosive materials. 10/1/2024 CEIR11 Basics of Civil Engineering 36  For every site there is an ideal use, For every use there is an ideal site. 10/1/2024 CEIR11 Basics of Civil Engineering 37 Construction site selection ❖A proper site selection is one of the most important steps before beginning construction works. ❖The contractor or civil engineer should consider key factors affecting when selecting a site. ❖Site selection of a building should be done based upon some surveys of various aspects of the site such as the development of the site, cost, the stability of the proposed structure, and type of construction project- industrial, commercial or residential, etc. 10/1/2024 CEIR11 Basics of Civil Engineering 38 Factors affecting site selection ❖Multiple factors enter into the decision on whether to build a project on a given site. ❖Studies should be made to determine whether a site is suitable for the intended project. ❖Once selected, the same factors also influence how the project is laid out on a site. ❖Three main categories of factors provide influence to the site selection and layout process: ✓Natural Factors ✓Man-made Factors ✓Aesthetic Factors 10/1/2024 CEIR11 Basics of Civil Engineering 39 Natural Factors Geology ❖Rock outcroppings can indicate the presence of a shallow bedrock elevation. ❖Shallow bedrock can lead to foundation and trench excavation difficulties and expenses. ❖Shallow bedrock may be desirable for foundation anchorage for large structures. 10/1/2024 CEIR11 Basics of Civil Engineering 40 Natural Factors Terrain ❖The physical characteristics of the land are always important. ❖Large level facilities require level terrain on which to build in order to minimize earthwork cost. 10/1/2024 CEIR11 Basics of Civil Engineering 41 Natural Factors Hydrology ❖Surface Water Runoff ❖Floodways ❖Groundwater 10/1/2024 CEIR11 Basics of Civil Engineering 42 Natural Factors Soils ❖Soils at the site of construction should have: ✓ Ability to support foundations ✓ Ability to be compacted and maintain volume ✓ Ability to be drained 10/1/2024 CEIR11 Basics of Civil Engineering 43 Natural Factors Delicate Ecologies ❖Rare or protected vegetation ❖Wildlife- endangered species ❖Nesting areas 10/1/2024 CEIR11 Basics of Civil Engineering 44 Natural Factors Climate ❖Solar Orientation ❖Prevailing wind ❖Precipitation ❖Temperature 10/1/2024 CEIR11 Basics of Civil Engineering 45 Manmade Factors Existing Surrounding Land Use ❖Visual, Auditory and Olfactory ❖Compatibility of adjacent uses 10/1/2024 CEIR11 Basics of Civil Engineering 46 Manmade Factors Traffic & Transit ❖Can users get to/from site without causing congestion? ❖From what directions does traffic enter & leave? ❖Is public transit available nearby? ❖Are improvements to the system warranted? 10/1/2024 CEIR11 Basics of Civil Engineering 47 Manmade Factors Zoning ❖Zoning regulations help to regulate land use on sites for an organized development. ❖Restrictions on allowable land usage ❖Restrictions on building size and type ❖Restrictions and regulations on site development- Parking, Setbacks, Green space, Signage, etc.) 10/1/2024 CEIR11 Basics of Civil Engineering 48 Manmade Factors Other Regulations ❖Fire safety regulations ❖School boards ❖Residential associations ❖Other political entities 10/1/2024 CEIR11 Basics of Civil Engineering 49 Manmade Factors Utilities ❖Water supply ❖Sanitary Sewer ❖Natural Gas ❖Electric Power ❖Waste disposal ❖Availability & Capacity 10/1/2024 CEIR11 Basics of Civil Engineering 50 Manmade Factors Historical & Cultural Sites ❖Some existing land uses are protected or require extensive channels for relocation/elimination. Parks Churches Burial Grounds and Cemeteries Historical Sites Historical Buildings 10/1/2024 CEIR11 Basics of Civil Engineering 51 Manmade Factors Hazardous Materials ❖Could Hazardous Materials Exist On-Site? ❖Search titles of ownership ❖Review mapping & aerials ❖Check government registries ❖Site visual inspection ❖In depth exploration for verification and identification of materials ❖Remediation plans 10/1/2024 CEIR11 Basics of Civil Engineering 52 Aesthetic Factors Natural Features ❖Client may wish to protect natural features on-site as a part of the new development. Landforms Streams Ponds Woods 10/1/2024 CEIR11 Basics of Civil Engineering 53 Aesthetic Factors Spatial Patterns ❖Client may desire a particular space or view to be produced as a part of the design of the site. 10/1/2024 CEIR11 Basics of Civil Engineering 54 Site selection for residential building ✓Shape of the plot ✓Location of the plot ✓Availability of amenities ✓Water table ✓Sewerage system 10/1/2024 CEIR11 Basics of Civil Engineering 55 Site selection for residential building ✓Site should be in fully developed area or in the area which has potential of development. ✓Site should command a good view of landscape such a hill, river, lake, etc. ✓There should be good transport facilities such as railway, bus service, for going to office, college, market, etc. ✓Civic services such as water supply, drainage sewers, electric lines, telephone lines, etc. should be very near to the selected site so as to obtain their services with no extra cost. ✓Soil at site should not be of made-up type as far as possible. The buildings constructed over such soils normally undergo differential settlement and sometimes become the cause of collapse. Cracks in buildings in such conditions, are quite common. ✓Residential house site should be located away from the busy commercial roads. 10/1/2024 CEIR11 Basics of Civil Engineering 56  Site selection for residential building ✓The selected site should be large enough; both to ensure the building abundant light and air and to prevent any over dominance by the neighboring buildings. ✓The ground water table at the site should not be very high. ✓Good foundation soil should be available at reasonable depth. This aspect saves quite a bit in the cost of the building. ✓Residential site should not be located near workshops, factories, because such locations are subjected to continuous noise. ✓Orientation of the site also has some bearing on its selection. Site should be such that early morning sun and late evening sun is available in the building in summer and maximum sun light is available in most of winter. 10/1/2024 CEIR11 Basics of Civil Engineering 57 Site selection for commercial building ✓Location ✓Climate of region ✓Availability of raw materials ✓Cost and time frame ✓Drainage facilities on the site ✓Population of the region 10/1/2024 CEIR11 Basics of Civil Engineering 58 Lecture Objectives To introduce various components of buildings 10/1/2024 CEIR11 Basics of Civil Engineering 59 What is a structure? ❖Within the context of the built environment, the term ‘structure’ refers to anything that is constructed or built from interrelated parts with a fixed location on the ground. ❖This includes buildings, but can refer to any body that is designed to bear loads, even if it is not intended to be occupied by people (often referred as 'non-building' structures – such as bridges, tunnels, and so on). 10/1/2024 CEIR11 Basics of Civil Engineering 60 What is a structure? ❖A structure is a system of inter-connected elements to carry loads safely to under ground earth. ❖A building structure has two components: Framed structure Load bearing structure 10/1/2024 CEIR11 Basics of Civil Engineering 61 Transmission of loads in a structure 10/1/2024 CEIR11 Basics of Civil Engineering 62 Loads on a building Dead Loads It consist of the weights of the various structural members and the weights of any objects that are permanently attached to the structure. Eg: Self weight of the structure Live Loads Occupancy Loads Wind Loads Snow Loads Earthquake Loads Other Loads: ⁻ Blast Loads ⁻ Variance in temperatures ⁻ Uneven settling of soil 10/1/2024 CEIR11 Basics of Civil Engineering 63 Loads on a building 10/1/2024 CEIR11 Basics of Civil Engineering 64 Components of a building Any building has two parts: ▪ Sub structure: part of building below the ground level which transfers load from the superstructure to the foundation and underlying soil. ▪ Super structure: portion of a building constructed above the ground level which serves for the intended use of the building structure. 10/1/2024 CEIR11 Basics of Civil Engineering 65 Components of a building The various components of the superstructure are ▪Masonry units such as walls and columns ▪Floors ▪Doors, windows and other openings ▪Roof structures ▪Elevators, ramps and ▪Building finishes 10/1/2024 CEIR11 Basics of Civil Engineering 66 Components of a building 10/1/2024 CEIR11 Basics of Civil Engineering 67 Components of a building ❖Foundation Foundation or footing is a structural unit that uniformly distributes the load from superstructure to the underlying soil. This is the first structural unit to be constructed for any building construction. Foundations are of different types (Shallow & Deep foundations). 10/1/2024 CEIR11 Basics of Civil Engineering 68 Components of a building ❖Plinth Plinth is constructed above the ground level. It is a dividing layer between the sub-structure and super-structure. It is generally made of cement mortar and is usually 1.5 feet above the ground level to give protection from water and other elements of the building. It is capped by a beam called plinth beam. 10/1/2024 CEIR11 Basics of Civil Engineering 69 Components of a building ❖Columns /pillars They are vertical compression members built above ground level. A structural column takes the load coming from the slab above and transmits safely to the foundation. On the other hand an architectural column is made to improve building aesthetics. Columns Columns 10/1/2024 CEIR11 Basics of Civil Engineering 70 Components of a building ❖Beams & Slabs They form the horizontal components in a building generally built with RCC. For a single storey building, the top slab forms the roof. In case of multi-storey building, the beam transfers the load coming from the floor above the slab which is in turn transferred to the columns. Slabs Beams Beams 10/1/2024 CEIR11 Basics of Civil Engineering 71 Components of a building This building under construction has ground floor, first floor, second floor, and terrace floor. The vertical elements are the columns. The horizontal bands are the beams. The flat surface on which you can stand is the slab. 10/1/2024 CEIR11 Basics of Civil Engineering 72 Load bearing structures and framed structures Load bearing Cost is less Suitable up to three storeys Walls are thicker, hence floor area is reduced Not possible to alter the position of walls after construction Resistance is earthquake is poor Framed structures Cost is more Suitable for any number of storeys Walls are thinner, hence more floor area is available Position of walls may be changed whenever necessary Resistance is earthquake is good 10/1/2024 CEIR11 Basics of Civil Engineering 73 Components of a building This is a completed building as a framed structure. 10/1/2024 CEIR11 Basics of Civil Engineering 74 Components of a building ❖Column ❖Beam ❖Slab ❖Roof ❖Lintel 10/1/2024 CEIR11 Basics of Civil Engineering 75 RCC Column ❖Reinforced cement concrete (RCC) columns may be constructed in square, rectangular, hexagonal, or circular shapes. ❖Longitudinal reinforcements are provided to take up the major load coming over the columns. ❖Lateral ties are provided to keep the main reinforcement in position and to take up the shrinkage and temperature stresses. ❖They also provide lateral rigidity which checks the buckling of the longitudinal bars. ❖These ties may be provided in the form of spiral. 10/1/2024 CEIR11 Basics of Civil Engineering 76 10/1/2024 CEIR11 Basics of Civil Engineering 77 10/1/2024 CEIR11 Basics of Civil Engineering 78 Specification for RCC column ❖The spiral lateral ties are advantageous as they provide extra strength to the column. ❖The longitudinal bars should not be less than 0.8 percent and not more than 8 percent of the cross sectional area of the column. ❖The minimum concrete cover provided around the bar is 4 cm. ❖The pitch of the lateral ties is not more than 30 cm or the least lateral dimension of the column or sixteen times the smallest diameter of the longitudinal bar. ❖The volume of the lateral reinforcing steel should not be less than 4 percent of the total volume of column. ❖Minimum 4 and 6 numbers of longitudinal bars should be used for rectangular and circular column respectively. 10/1/2024 CEIR11 Basics of Civil Engineering 79 Placing of reinforcement steel Formwork is a mould including all supporting structures, used to shape and support the concrete until it attains sufficient strength to carry its own weight. 10/1/2024 CEIR11 Basics of Civil Engineering 80 Placing of reinforcement steel Procedure ❖Longitudinal bars and lateral ties are fixed in the position and then shuttering is erected. ❖With the aid of suitable fillets, the gap between bars and the shuttering maintained so as to have suitable concrete cover. ❖Concrete is poured into it and well compacted. ❖Again the shuttering is provided for the second stage and concreting is done as usual. ❖This process of casting is continued till the full column is complete but rate of casting is not more than 2 meters height per hour. ❖The concreting in the column should be stopped a few centimeters below the level of the beams running into the columns. This portion of the column is concreted with the beam. 10/1/2024 CEIR11 Basics of Civil Engineering 81 10/1/2024 CEIR11 Basics of Civil Engineering 82 10/1/2024 CEIR11 Basics of Civil Engineering 83 Steel Columns ❖Steel columns are more dependable and safe compared to cast iron and other metal columns. 10/1/2024 CEIR11 Basics of Civil Engineering 84 Steel columns 10/1/2024 CEIR11 Basics of Civil Engineering 85 Components of a building ❖Lintel ❖Column ❖Beam ❖Slab ❖Roof 10/1/2024 CEIR11 Basics of Civil Engineering 86 Beam ❖A beam is a horizontal structural member subjected to a system of external forces at right angles to its axis. ❖In general, the beams can be classified as follows. 1)Cantilever Beam 2)Simply supported beam 3)Over hanging beam 4)Rigidly fixed beam 5)Continuous beam 10/1/2024 CEIR11 Basics of Civil Engineering 87 Types of beams based on support conditions ❖Cantilever beam: A beam fixed in one end and free at the other is called as cantilever beam. ❖Simply supported beam: A beam supported or resting freely on walls or columns at it both ends, is known as simply supported beam. ❖Over hanging beam: A beam having its end portion extended beyond the support is known as an over hanging beam. ❖Continuous Beam: A beam supported on more than two supports is known as a continuous beam. It may or may not be an over hanging beam. ❖Rigidly Fixed Beam: A beam whose both ends, are rigidly fixed in walls is known as rigidly fixed beam or built-in beam. 10/1/2024 CEIR11 Basics of Civil Engineering 88 Types of loading 1.Concentrated or point toad 2.Uniformly distributed load 3.Uniformly varying load 4.Arbitrary load 5.Couple loading 10/1/2024 CEIR11 Basics of Civil Engineering 89 Span of the Beam ❖The horizontal distance between the supporting walls is known as clear span of the beam. ❖The horizontal distance between the lines of action of the supporting walls is known as effective span. 10/1/2024 CEIR11 Basics of Civil Engineering 90 Components of a building ❖Lintel ❖Column ❖Beam ❖Slab ❖Roof 10/1/2024 CEIR11 Basics of Civil Engineering 91 Slab ❖A slab is a structural element with its thickness being small (~150 mm) compared to the other two dimensions. ❖Most of the slabs in construction are rectangular in plan and can be divided into two categories. ✓One way slabs, simply supported, cantilevered or continuous; bending in one direction only. ✓Two way slabs, simply supported, cantilevered or continuous; bending in two directions. 10/1/2024 CEIR11 Basics of Civil Engineering 92 One way Slab ❖Length-to-breadth (L/B) ratio of slab ≥ 2 ❖One way slabs span in one direction only and may have simply supported beam or edges over which the slab is continuous. ❖The assumption is that of unidirectional bending in the direction of the span. 10/1/2024 CEIR11 Basics of Civil Engineering 93 Two way Slab ❖Length-to-breadth (L/B) ratio of slab < 2 ❖The term two-way slab may be attributed to such cases in which the load is carried in two directions. 10/1/2024 CEIR11 Basics of Civil Engineering 94 Components of a building ❖Walls Walls are vertical elements which supports the roof. They may also act as partition walls or compound walls. These are generally made of masonry i.e. bricks, stones, concrete blocks etc. Walls provide an enclosure and protect against wind, sunshine, rain etc. 10/1/2024 CEIR11 Basics of Civil Engineering 95 Components of a building ❖Door & Windows Openings are necessary in buildings for passages inside and outside the buildings. They also provide light, heat, and ventilation. Traditionally, doors and windows are made of wood and glass. 10/1/2024 CEIR11 Basics of Civil Engineering 96 Components of a building Lintel 10/1/2024 CEIR11 Basics of Civil Engineering 97 Components of a building ❖Lintel It is a horizontal structural element that spans the space or opening between two vertical supports. It is usually provided over doors, windows, portals, etc. These structures support the weight of the wall coming over the opening. In residential buildings, lintels can be made of either concrete or bricks. Lintel 10/1/2024 CEIR11 Basics of Civil Engineering 98 Lintel A lintel is a horizontal structural member which is placed across openings such as doors, windows, and corridors, to support the portion of the structure above it. ❖Wooden lintel ❖Brick lintel (Arches) ❖Stone lintel ❖Steel lintel ❖RCC lintel 10/1/2024 CEIR11 Basics of Civil Engineering 99 Lintel Wooden lintel ❖Oldest type of lintels ❖They are used in hilly areas where timber is available. ❖Only good quality timber with a coat of suitable preservative should be used. ❖One piece of timber or a built up section may be used as a lintel. ❖Ends of lintels rest on a mortar on the walls for a minimum width of 15 cm. ❖If it is used in ventilated places, it is liable for decay. ❖It is easily liable to catch fire. 10/1/2024 CEIR11 Basics of Civil Engineering 100 Lintel Brick lintel (or arches) ❖Brick lintels are used for openings, generally exceeding 1 m span and light loads. ❖Bricks used should be hard, well-burnt, copper-coloured, free from cracks and straight edged. ❖The depth of the lintel varies from 10 cm to 30 cm depending upon the span. ❖A centering or timber supporting is required to construct brick lintel. 10/1/2024 CEIR11 Basics of Civil Engineering 101 Lintel When lintels are constructed to span over large opening, mild reinforcing bars are used with rich cement mortar. It is known as reinforced brick lintel. 10/1/2024 CEIR11 Basics of Civil Engineering 102 Lintel Stone lintel ❖Stone lintels are used in stone masonry structures and buildings faced with stones. ❖It may be constructed of a single piece or more than one piece. ❖The use is restricted to monumental buildings or in hilly areas due to high cost and weakness in withstanding excessive transverse stresses. ❖The least thickness of the stone lintel is about 7.5 cm and as a thumb rule, the thickness is taken as at least 1 mm per one cm length of the opening. 10/1/2024 CEIR11 Basics of Civil Engineering 103 Lintel Steel lintel ❖Steel angles are used for spanning small openings and rolled steel joists are used for heavy loading and large spans. ❖Some times, a combination of two or more joists is used. ❖The system may be embedded in cement concrete to protect steel, from fire and corrosion. 10/1/2024 CEIR11 Basics of Civil Engineering 104 RCC Lintel ❖Economical and simple in construction, and are commonly used. ❖They are more durable, strong and fire-resistant. ❖It consists of a rectangular or square concrete section reinforced with mild steel bars. The depth of lintel and the amount of the reinforcement is governed by the intensity of load, the type of support and the span. ❖Generally 1:2:4 concrete is used. It can be pre-cast or cast-in-situ. ❖Precast RCC lintels are preferred for small spans up to 2 m. ❖It increases the speed of the construction and quality control is better in this case. For cast-in- situ lintels, a centering is erected. 10/1/2024 CEIR11 Basics of Civil Engineering 105 Loads on Lintel ❖A lintel carries the weight of the wall enclosed in a triangle with a base equal to the effective span of the lintel and the side angle of 60°. ❖This consideration is based on the assumption that if a lintel falls, the amount of brickwork which would collapse with it would probably be something between a semi-circular arch and an equilateral triangle. ❖This is only valid when the lintel is placed in the middle of the wall. 10/1/2024 CEIR11 Basics of Civil Engineering 106 Components of a building ❖Parapets Parapets are low protective walls extended above the roof slab, along the edges of the roof. Parapets are installed for flat roofs. It acts as a safety barrier for people using the roof and protects the edges of buildings from wind loads. 10/1/2024 CEIR11 Basics of Civil Engineering 107 Components of a building ❖Stairs and lifts A stair is a sequence of steps that connects different floors in a building structure. The space occupied by a stair is called the stairwell. Stairs can be made of wood, RCC, steel, glass, etc. Electric lifts are provided in building having more than 4 floors including ground floor. 10/1/2024 CEIR11 Basics of Civil Engineering 108 Components of a building Structural components of a reinforced concrete building (G+1) 10/1/2024 CEIR11 Basics of Civil Engineering 109 Components of a building Structural components of a reinforced concrete building (with basement/ cellar) 10/1/2024 CEIR11 Basics of Civil Engineering 110 Building Services Building services are the systems installed in buildings to make them comfortable, functional, efficient and safe. They include the mechanical, electrical, and plumbing systems in a building- for this reason they are also called MEP services. They play a central role in contributing to the design of a building- in terms of overall strategies and standards to be achieved, façade engineering, the weights, sizes and location of major plant and equipment, the position of vertical service risers, routes for the distribution of horizontal services, drainage, energy sources, sustainability, and so on. 10/1/2024 CEIR11 Basics of Civil Engineering 111 Building Services 10/1/2024 CEIR11 Basics of Civil Engineering 112 Building Services ❖Mechanical Services Firefighting Systems Elevators & Escalators HVAC Systems (heating, ventilation, and air-conditioning systems) Gas Supply Systems (such as for heating and cooking in residential buildings, or oxygen and nitrogen in hospitals) Compressed Air Systems used in industries HVAC DUCT CHILLER UNIT 10/1/2024 CEIR11 Basics of Civil Engineering 113 Building Services ❖Electrical Services Power Supply Backup Power (such as diesel generators) Emergency Power (such as battery-based uninterrupted power supply) 10/1/2024 CEIR11 Basics of Civil Engineering 114 Building Services ❖Plumbing Systems Water Supply Drainage of Wastes Water Recycling Systems (these allow you to recover the water from your waste and re-use that water for low-grade applications such as flushing) Rainwater Harvesting Storm Water Drainage 10/1/2024 CEIR11 Basics of Civil Engineering 115 Building Services ❖Data based Systems Security Systems Fire Alarm Systems Building Management Systems Public Address Systems Cable TV Systems Data Networks Voice Networks Door access control Boom barrier 10/1/2024 CEIR11 Basics of Civil Engineering 116 Damp Proof Course (DPC) Damp proof course is a layer of water proofing material such as asphalt or waterproof cement. Walls are constructed above the damp proof course. Damp proof course prevents surface water from rising into the walls. Dampness reduces the strength of the walls and creates unhealthy living conditions. Also it affects the paint and plaster and increasing the cost of maintenance. 10/1/2024 CEIR11 Basics of Civil Engineering 117 Floor This is the surface on which we do most of our activities. Floorings is laid over the filling of the plinth and on subsequent floors. Flooring can be done with different materials, but care must be given that the ground below the floor is well compacted. Flooring is done to prevent dampness from rising to the top and to have a firm platform that can be kept hygienic and clean. 10/1/2024 CEIR11 Basics of Civil Engineering 118 Walls Walls are the vertical elements on which the roof finally rests. They can be made of different materials like bricks, stones, mud, concrete blocks, lateritic blocks etc. If the walls are very long, columns can be provided. Walls provide privacy and enclosure. Walls also provide security and protection against natural elements such as wind, rain and sunshine. Openings are to be provided in wall for access and ventilation. 10/1/2024 CEIR11 Basics of Civil Engineering 119 Openings Openings are normally provided in the walls as door, windows and ventilators. Doors provide access; windows and ventilators provide light and ventilation. Lintels are constructed just above the openings. Sill is the part of the wall that is just below the window. 10/1/2024 CEIR11 Basics of Civil Engineering 120 Doors These are the openings which allow entrance in the building and circulation through different rooms. 10/1/2024 CEIR11 Basics of Civil Engineering 121 Windows These are opening generally constructed in the external wall which provides air and light inside the rooms 10/1/2024 CEIR11 Basics of Civil Engineering 122 Stairs A stair is a sequence of steps and it is provided to afford the means of ascent and descent between the floors and landings. The apartment or room of a building in which stair is located is called staircase. The space or opening occupied by the stair is called a stairway. There are different kind of stairs are used in buildings, like RCC stair, wooden stair, metal stair, brick stair etc. 10/1/2024 CEIR11 Basics of Civil Engineering 123 Lintels A beam that carries the wall load lies above doors and windows It is normally a stone slab or a concrete slab. A lintel is a horizontal structural member which is placed across openings such as doors, windows, and corridors, to support the portion of the structure above it. Types Wooden lintel Brick lintel (Arches) Stone lintel Steel lintel RCC lintel 10/1/2024 CEIR11 Basics of Civil Engineering 124 Wooden Lintels Oldest type of lintels Now a days they are used in hilly areas where timber is available. Only good quality timber with a coat of suitable preservative should be used. One piece of timber or a built-up section may be used as a lintel. Ends of lintels rest on mortar on the walls for a minimum width of 15 cm. If it is used in ventilated places, it is liable for decay It is easily liable to catch fire. 10/1/2024 CEIR11 Basics of Civil Engineering 125 Brick Lintels Brick lintels are used for openings, generally exceeding 1m span and light loads. Bricks used should be hard, well-burnt, copper- coloured, free from cracks and straight edged. The depth of the lintel varies from to 10 cm to 30 cm depending upon the span. A centering or timber supporting is required to construct brick lintel. When lintels are constructed to span over large opening, mild reinforcing bars are used with rich cement mortar. It is known as reinforced brick lintel. 10/1/2024 CEIR11 Basics of Civil Engineering 126 Stone Lintels Stone lintels are used in stone masonry structures and buildings faced with stones. It may be constructed of a single piece or more than one piece. Its use is restricted to monumental buildings or in hilly areas due to high cost and weakness in withstanding excessive stresses. The least thickness of the stone lintel is about 7.5 cm and as a thumb rule the thickness is taken as at least 1 mm per one cm length of the opening. 10/1/2024 CEIR11 Basics of Civil Engineering 127 Steel Lintels Steel angles are used for spanning small openings and rolled steel joists are used for heavy loading and large spans. Sometimes, a combination of two or more joists is used. The system may be embedded in cement concrete to protect steel, from fire and corrosion. 10/1/2024 CEIR11 Basics of Civil Engineering 128 RCC Lintels Economical and simple in construction and are commonly used. They are more durable, strong and fire-resistant. It consists of a rectangular or square concrete section reinforced with mild steel bars. The depth of lintel and the amount of the reinforcement is governed by the intensity of load, the type of support and the span. Generally 1:2:4 concrete is used. It can be pre-cast or cast-in-situ. Precast RCC lintels are preferred for small spans up to 2 m. It increase the speed of the construction and quality control is better in this case. For cast-in- situ lintels, a centering is erected 10/1/2024 CEIR11 Basics of Civil Engineering 129 Loads on Lintels A lintel carries the weight of the wall enclosed in a triangle with a base equal to the effective span of the lintel and the side angle of 60°. This consideration is based on the assumption that if a lintel falls, the amount of brickwork which would collapse with it would probably be something between a semi- circular arch and an equilateral triangle. This is only valid when the lintel is placed in the middle of the wall. 10/1/2024 CEIR11 Basics of Civil Engineering 130 Columns Vertical elements Types Reinforced Concrete Steel Timber Brick Block Stone Column 10/1/2024 CEIR11 Basics of Civil Engineering 131 RCC Columns 10/1/2024 CEIR11 Basics of Civil Engineering 132 Beam A beam is a horizontal structural member subjected to a system of external forces at right angles to its axis. In general the beams can be classified as follows: Cantilever Beam Simply supported beam Over hanging beam Rigidly fixed beam Continuous beam 10/1/2024 CEIR11 Basics of Civil Engineering 133 Types of beams based on support conditions Cantilever beam: A beam fixed in one end and free at the other is called as cantilever beam. Simply supported beam: A beam supported or resting freely on walls or columns at it both ends, is known as simply supported beam. Over hanging beam: A beam having its end portion extended beyond the support is known as an over hanging beam. Continuous Beam: A beam supported on more than two supports is known as a continuous beam. It may or may not be an over hanging beam. Rigidly Fixed Beam: A beam whose both ends, are rigidly fixed in walls is known as rigidly fixed beam or built-in beam. 10/1/2024 CEIR11 Basics of Civil Engineering 134 Span of the Beam The horizontal distance between the supporting walls is known as clear span of the beam. The horizontal distance between the lines of action of the supporting walls is known as effective span. 10/1/2024 CEIR11 Basics of Civil Engineering 135 Slab A slab is a structural element with its thickness being small (~150 mm) compared to the other two dimensions. Most of the slabs in construction are rectangular in plan and can be divided into two categories. One-way slabs - bending in one direction only. Two-way slabs - bending in two directions. 10/1/2024 CEIR11 Basics of Civil Engineering 136 One Way Slab – (Length-to-breadth (L/B) ratio of slab ≥ 2) One-way slabs span in one direction only and may have simply supported beam or edges over which the slab is continuous. The assumption is that of unidirectional bending in the direction of the span. 10/1/2024 CEIR11 Basics of Civil Engineering 137 Two Way Slab - (Length-to-breadth (L/B) ratio of slab < 2) Supported by beams on all four sides 10/1/2024 CEIR11 Basics of Civil Engineering 138 Lecture Objectives To introduce various components of buildings To introduce load bearing and framed structures 10/1/2024 CEIR11 Basics of Civil Engineering 139  Roof Provides protection for the building and the people living in it. The roof rests on the walls and requires proper anchoring so that wind and other mechanical impact cannot destroy it. Roof is typically made of RCC, stone slab, tiles etc. Classification of roof Pitched or Sloping Roofs Flat Roofs Curved Roofs 10/1/2024 CEIR11 Basics of Civil Engineering 140 Pitched Roof It is the most common form of roof Cheapest alternative for covering a structure. They are always constructed in wood or steel. Wooden pitched roof consists of a system of joists, rafters and purlins arranged in the form of a triangular shaped support known as truss. The lower ends of the rafter rest upon the wall plates and at their upper end they are connected to a common ridge piece. 10/1/2024 CEIR11 Basics of Civil Engineering 141 Roof Covering for Pitched Roofs The various types of roof covering are Thatch covering Shingles, Tiles, Slates Asbestos-cement sheets Galvanized corrugated iron sheets 10/1/2024 CEIR11 Basics of Civil Engineering 142 Flat Roofs Where the rainfall is low, flat roofing is preferred over sloping roof. A gentle slope is given to the surface for the free flow of rainwater. 10/1/2024 CEIR11 Basics of Civil Engineering 143 Advantages of Flat Roofs The construction of roof is simplified. It is easier to make a flat roof as fire proof than a sloping roof. The roof area can be utilized for roof gardens, drying yards, etc. The terrace can conveniently be used for sleeping in hot season. The construction work of upper floors can easily be started. In case of a pitched roof, the entire roof is to be removed and is to be replaced by a new floor under such circumstances. A flat roof is found to be economical than a pitched roof. 10/1/2024 CEIR11 Basics of Civil Engineering 144 Disadvantages Flat roofs cannot be used for long spans. Cracks are developed on the surface of the roof, when the variation in temperature is high. Pockets of water are formed on the surface of the roof, if slopes are not sufficient. This leads to the leakage of the roof. At places where rainfall is heavy, flat roofs are not desirable. 10/1/2024 CEIR11 Basics of Civil Engineering 145 Curved Roofs These are just the modification of pitched roofs and are frequently used to cover large areas. Shell roofs and domes are the types of curved roofs. They are used in factories, monuments etc. They are constructed of timber, steel or RCC. Shell roof are of two types: North light shell roof Barrel vault shell roof 10/1/2024 CEIR11 Basics of Civil Engineering 146 North light shell roof Industrial roof, design to maximize the amount of diffused daylight reaching inside the factory This type of roof consist of series of parallel mono- pitch roof with glazing in the vertical edges below the ridges with usually faces north Cheap construction and provide pleasant appearance. 10/1/2024 CEIR11 Basics of Civil Engineering 147 Barrel vault shell roof A barrel vault is a continuous arched shape that may approximate a semi-cylinder in form, resembling the roof of a tunnel, or may be pointed at its apex. It is typically formed by a series of arches or vaults placed side by side or by a continuous shell. 10/1/2024 CEIR11 Basics of Civil Engineering 148 Surfaces / Finishes External finishes are the outer most layer of protection, which protect the structure from weathering. Internal finishes are the layers given on internal faces. They give durability and pleasing appearance to the inside. 10/1/2024 CEIR11 Basics of Civil Engineering 149 10/1/2024 CEIR11 Basics of Civil Engineering 150 Building Services Building services are the systems installed in buildings to make them comfortable, functional, efficient and safe. They include the mechanical, electrical, and plumbing systems in a building- for this reason they are also called MEP services. They play a central role in contributing to the design of a building- in terms of overall strategies and standards to be achieved, façade engineering, the weights, sizes and location of major plant and equipment, the position of vertical service risers, routes for the distribution of horizontal services, drainage, energy sources, sustainability, and so on. 10/1/2024 CEIR11 Basics of Civil Engineering 151 Building Services ❖Mechanical Services Firefighting Systems Elevators & Escalators HVAC Systems (heating, ventilation, and air-conditioning systems) Gas Supply Systems (such as for heating and cooking in residential buildings, or oxygen and nitrogen in hospitals) Compressed Air Systems used in industries 10/1/2024 CEIR11 Basics of Civil Engineering 152 Building Services ❖Electrical Services Power Supply Backup Power (such as diesel generators) Emergency Power (such as battery-based uninterrupted power supply) 10/1/2024 CEIR11 Basics of Civil Engineering 153 Building Services ❖Plumbing Systems Water Supply Drainage of Wastes Water Recycling Systems (these allow you to recover the water from your waste and re-use that water for low-grade applications such as flushing) Rainwater Harvesting Storm Water Drainage 10/1/2024 CEIR11 Basics of Civil Engineering 154 Building Services Data based Systems Security Systems Fire Alarm Systems Building Management Systems Public Address Systems Cable TV Systems Data Networks Voice Networks 10/1/2024 CEIR11 Basics of Civil Engineering 155 MASONRY  What is masonry? ❖The art of laying bricks (or stones) in mortar in a proper systematic manner gives a homogeneous mass, which can withstand forces without disintegration, is called brick (or stone) masonry. ❖Masonry is normally used for construction of walls. Brick masonry Stone masonry 10/1/2024 CEIR11 Basics of Civil Engineering 157 Functions of masonry It performs a variety of functions such as : 1. Supporting loads 2. Subdividing space 3. Providing thermal and acoustic insulation 4. Affording fire and weather protection etc. 10/1/2024 CEIR11 Basics of Civil Engineering 158 Mortar Mortar is the pasty material formed by the addition of water to a mixture of fine aggregate (sand) and cement or lime. Generally, the following types of mortar are in use Mud mortar Lime mortar Lime surkhi mortar Cement mortar and Cement lime mortar or lime- cement mortar 10/1/2024 CEIR11 Basics of Civil Engineering 159 Terminology used in Brick Masonry ❖Frog : Depressions provided in the face of the brick. ❖Bed: The bottom surface of the brick when it is laid flat is called bed. ❖Course: A complete layer of bricks laid on the same level is called a course. ❖Header: The end face of the brick when it is laid flat is called as header (9cm x 9cm) ❖Stretcher: The side surface of bricks visible in elevation when the brick is laid flat is called the stretcher (19 cm x 9 cm). 10/1/2024 CEIR11 Basics of Civil Engineering 160 Terminology used in Brick Masonry ❖Bed joint : The horizontal joints between two successive courses are known as bed joints. ❖Perpend: These are the joints between bricks either in longitudinal or cross directions. ❖Bat: The brick which is cut across its width is called as bat. ❖Closer: The brick which is cut across its length in such a way as one long face remains intact is called as closer. 10/1/2024 CEIR11 Basics of Civil Engineering 161 Bat & Closer 10/1/2024 CEIR11 Basics of Civil Engineering 162 Principles in Brick Masonry Construction ❖Good brick masonry should utilize bricks which are sound, hard, well-burnt, and tough with uniform color, shape and size. ❖The brick should be compact, homogeneous and free from holes, cracks, air-bubbles and stone lumps. ❖In the brick work, the bricks should be laid on their beds with the frogs pointing upwards. ❖The brick courses should be laid truly horizontal and should have truly vertical, joints. ❖As far as possible, the use of brick-bats should be discouraged. ❖Finished brickwork in lime mortar should be cured for a period of 2 to 3 weeks. This period can be reduced to 1 to 2 weeks in case of brickwork with cement mortar. 10/1/2024 CEIR11 Basics of Civil Engineering 163 Bonds in Brick Masonry ❖Bonding is a process of arrangement of bricks and mortars to tie them together in a mass of brickwork. ❖It should have a minimum of vertical joints in any part of the work. It is a weak portion of brickwork and should not be continuous in two successive courses. ❖A wall having continuous vertical joints acts as an independent column. Hence, the load on the wall may not be uniformly distributed. ❖A stronger and durable brick masonry construction should not have continuous vertical joints. It shall distribute load on a wider area and thereby minimize the tendency to settle. 10/1/2024 CEIR11 Basics of Civil Engineering 164 Bonds in Brick Masonry The various types of bond are ❖Stretcher bond ❖Header bond ❖English bond ❖Flemish bond 10/1/2024 CEIR11 Basics of Civil Engineering 165 Bonds in Brick Masonry Stretcher bond ❖In this type of bond, all the bricks are laid with their lengths in the direction of the wall. ❖This pattern is used for walls having thickness of 9 cm only. 10/1/2024 CEIR11 Basics of Civil Engineering 166 Bonds in Brick Masonry Header bond ❖In this type of bond, all the bricks are laid with their ends towards the face of the wall. ❖This type of arrangement is suitable for walls, which are one brick thick. 10/1/2024 CEIR11 Basics of Civil Engineering 167  English bond ❖In this type of bond, alternate courses of headers and stretchers are laid. ❖Each alternate header should be centrally placed over a stretcher. ❖Continuous vertical joint should not be allowed except at stopped end. ❖The joints on the header course should be made thinner than those in the stretcher course. This is because of the fact that the number of vertical joints in the stretcher course are half the number of joints in the header course. 10/1/2024 CEIR11 Basics of Civil Engineering 168 Bonds in Brick Masonry Double Flemish bond ❖In this bond, alternate headers and stretchers are laid in each course. ❖This type of bond is better in appearance than the English bond. The facing and back are of the same appearance. ❖The Brick bats are used in case of walls having thickness equivalent to odd number of half bricks. 10/1/2024 CEIR11 Basics of Civil Engineering 169 Bonds in Brick Masonry Flemish bond 10/1/2024 CEIR11 Basics of Civil Engineering 170  Single & Double Flemish bond 10/1/2024 CEIR11 Basics of Civil Engineering 171 STONE MASONRY ❖The construction of stones bonded together with mortar is termed as stone masonry. ❖The stones are available in abundance in nature, and hence they provide an economical material for the construction. ❖Used for construction of various building components such as walls, columns, footings, arches, lintels, beams etc. 10/1/2024 CEIR11 Basics of Civil Engineering 172 Important Points in Stone Masonry ❖Stones should be strong, rough and hard. ❖Each stone should be well-watered before use. ❖All the stones should be laid on their natural bed. ❖Proper bond should be maintained; formation of vertical joints should be avoided. ❖Small stone pieces should be used for facing. ❖The wall should be raised uniformly throughout its length. ❖Mortar should be in proper proportion. ❖After the construction is over, the whole masonry work should be kept wet for at least 2 to 4 weeks. 10/1/2024 CEIR11 Basics of Civil Engineering 173 Through Stones A stone that is set with its longest dimension perpendicular to the face of a wall and whose length is equal to the thickness of the wall. 10/1/2024 CEIR11 Basics of Civil Engineering 174 Classification of Stone Masonry Based on the arrangement of the stone in the construction and degree of refinement in the surface finish, the stone masonry can be classified broadly in the following two categories. 1.Rubble masonry 2.Ashlar masonry 10/1/2024 CEIR11 Basics of Civil Engineering 175 Classification of Stone Masonry Rubble Masonry ❖In this type of masonry, stones of irregular sizes and shapes are used. ❖The stones used are either undressed or roughly dressed having wider joints. ❖The stones, as obtained from quarry, are taken for use in the same form or they are broken and shaped in suitable sizes by means of hammer as the work proceeds. 10/1/2024 CEIR11 Basics of Civil Engineering 176 Rubble Masonry 1.Random Rubble Masonry ❖In this type of masonry, the stones used are of widely different sizes. This is the roughest and cheapest form of stone masonry. ❖In coursed random rubble masonry, the masonry work is carried out in courses such that the stones in a particular course are of equal heights. 10/1/2024 CEIR11 Basics of Civil Engineering 177 Rubble Masonry 2.Square Rubble Masonry ❖In this type of masonry, stones having straight bed and sides are used. ❖The stones are usually squared and brought to a hammer dressed or straight cut finish. ❖In the coursed squared rubble masonry, the work is carried out in courses of varying depth. 10/1/2024 CEIR11 Basics of Civil Engineering 178 Rubble Masonry 3. Dry Rubble Masonry ❖In this type of masonry, mortar is not used in the joints. This type of construction is the cheapest and requires more skill in construction. ❖This may be used for non-load bearing walls such as compound wall etc. 10/1/2024 CEIR11 Basics of Civil Engineering 179 Rubble Masonry 4. Flint Rubble Masonry ❖In this type of rubble masonry, stones used are flints or cobbles. ❖These are irregularly shaped modules of silica. The stones are extremely hard. 10/1/2024 CEIR11 Basics of Civil Engineering 180 Ashlar Masonry ❖In this type of construction, no irregular stones are used. ❖The stones used in this masonry are rectangular blocks and are all dressed finely with chisel. ❖The courses are not necessarily of the same height. It may vary from 25 to 30 cm. 10/1/2024 CEIR11 Basics of Civil Engineering 181 Types of Ashlar Masonry 1. Ashlar rough-tooled masonry ❖In this type of ashlar masonry, the beds and sides are finely chisel-dressed. ❖But the face is made rough by means of tools. 2. Ashlar rock or quarry faced masonry ❖In Ashlar Quarry Faced masonry, the stone blocks are finely dressed on all sides except for the exposed face, which is left rough and only partially worked 10/1/2024 CEIR11 Basics of Civil Engineering 182 Types of Ashlar Masonry 3. Ashlar chamfered masonry ❖the stone blocks are dressed such that the edges of the exposed face are chamfered at a uniform angle, typically 45 degrees, while the central part of the face may be left either smooth or slightly rough. 4. Ashlar block-in-coarse masonry ❖This is combination of rubble masonry and Ashlar masonry. ❖In this type of masonry, the face work is provided with rough tooled (or hammer dressed stones) and backing of the wall made in rubble masonry. 10/1/2024 CEIR11 Basics of Civil Engineering 183  Ashlar rough-tooled Ashlar rock or quarry faced 10/1/2024 CEIR11 Basics of Civil Engineering 184  Comparison between Stone and Brick Masonry ❖Cost of stone masonry work is more, as it requires more skilled labor. ❖Due to various sizes and shapes of stone, complicated lifting devices are required in the construction. But bricks having regular shape and uniform size, can be moved easily by manual labor. ❖In the case of brick masonry, any mortar can be used. In the case of stone masonry, mortars other than cement is required (cement mortar will not be having any bond with the stone surface). ❖In the case of stone masonry, the dead weight is more because it is comparatively heavy, for the same reason, it is suitable for under water construction. ❖Stone work is stronger than brick work. 10/1/2024 CEIR11 Basics of Civil Engineering 185