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BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Building Construction and Construction Materials UNIT 1 OVERVIEW OF BUILDING COMPONENTS Unit Content: Introduction...

BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Building Construction and Construction Materials UNIT 1 OVERVIEW OF BUILDING COMPONENTS Unit Content: Introduction Classification of Buildings as per National Building Code Group A to I Types of constructions Learn about the Building components and its functions Course Outcome CO201.4: Identify components of building structures (CO) Covered for CO201.5: Propose suitable type of foundation for building this unit: structures Number Lectures EIGHT planned in Teaching Plan: Reference: Building construction by Foundation Publishing by S N P Shrivastava Building construction, Publishing-House Anand, by Ranga wala Lecture Notes Page | 1  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 01 Topics to cover: Concept Map and Classification of Buildings as per National Building code Group A to I part 01 National Building Code: National Building Code (NBC) is like a Standard Guidelines provided for the construction of buildings in India regarding materials, structural design and construction (including safety), building and plumbing services approach to sustainability. Purpose: Lecture Notes Page | 2  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) This helps to protect our building from fire, structural collapse, and general deterioration to minimize safety incidents and ensure the safety of the public. It will give proper guidelines to get the proper good buildings as per the classification of building A to I. The engineers should have sufficient knowledge in the construction of buildings and non- building structures. The building components can be classified from A to I are as follows: Group A Residential buildings Group B Educational buildings Group C Institutional buildings Group D Assembly buildings Group E Business buildings Group F Mercantile buildings Group G Industrial buildings Group H Storage buildings Group I Hazardous buildings. Group A - Residential buildings such as bungalows, flats, dormitories, Lodging or rooming houses, Apartments, Hotels etc., The Residential buildings can be, Case 01 - Lodging or rooming houses Case 02 - One or two-family private dwellings Case 03 - Dormitories Case 04 - Apartment houses(flats) Case 05 - Hotels Case 06 - Hotels (Starred) Group B – Educational buildings Educational buildings such as schools, colleges, libraries, universities, etc., Case 01 - Schools up to secondary level Case 02 - All others/Training centres Lecture Notes Page | 3  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 02 Topics to cover: Classification of Buildings as per National Building code Group A to I. Group C – Institutional Buildings The institutional buildings can be homes for the aged people, jails, prisons, mental hospitals, reformatories, etc. Case 01 - Hospitals and sanatoria Case 02 - Custodial institutions Case 03 - Penal and Mental institutions Group D – Assembly buildings Assembly buildings where group of people gather for amusement, recreation, religious, social, travel and similar purposes and they include exhibition halls, museums, skating rings, restaurants, gymnasiums, etc. The assembly Buildings can be Case 01 - Buildings having a theatrical or motion picture or any other stage and fixed seats or over 1000 persons. Case 02 - Buildings having a theatrical or motion picture or any other stage and fixed seats up to 1000 persons. Case 03 - Buildings without a permanent stage having accommodation for 300 or more persons but no permanent seating arrangement. Case 04 - Buildings without a permanent stage having accommodation for less than 300 persons with no permanent seating arrangements. Case 05 - All other structures including temporary structures designed for assembly of people not covered by sub-divisions 1 and 4th case, at ground level. Case 06 - Buildings having mixed occupancies providing facilities such as shopping, cinema theatres and restaurants. Case 07 - All other structures, elevated or underground, for assembly of people not covered sub-divisions 1st and 6th case. Group E - Business buildings The Business buildings can be banks, offices, shops, courts, stores, markets, etc. Case 01 – Offices, banks, professional establishments, like offices of architects, engineers, doctors, lawyers and police stations. Lecture Notes Page | 4  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Case 02 – Laboratories, research establishments, libraries and test houses. Case 03 – Computer installations. Case 04 – Telephone exchanges. Case 05 – Broadcasting stations and T.V stations. Group F – Mercantile Buildings The Mercantile buildings are Case 01 - Shops, stores, departmental stores markets with area up to 500m2. Case 02 – Shops, departmental stores markets with area more than 500m2. Case 03 – Underground shopping centres, storage and service facilities incidental to the sale of merchandise and located in the same building shall be included under this group. Group G – Industrial Buildings The industrial Buildings can be factories, workshops, laboratories, pumping stations refineries, gas plants, mills, dairies, etc. Case 01 – Buildings used for low hazard industries. Case 02 – Buildings used for moderate hazard industries. Case 03 – Building used for high hazard industries. Lecture Number: 03 Topics to cover: Types of construction – Load bearing structure Types of Constructions: Normally construction means the building the components of a building. We are dividing the structures in to sub structure and super structures. Usually in the construction there will be major loads like live load and dead load. The people who are living in that house are considered as live load, the non-living objects like machines, furniture etc., The load of that building will be transferred from the building super structure to sub structure that is up to foundation. The construction is classified according to how the load is transferred from super structure to sub-structure. We have three types of constructions is used in construction of buildings: Load bearing structures Framed structures Composite structures Lecture Notes Page | 5  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) LOAD BEARING STRUCTURES: The load bearing structure is the one which consists of a slab, wall and foundation. In this case there will be no beam or column. If the load is transferred from the slab to the wall and to the foundation means that structure is considered as load bearing structures that is load is transferred vertically downwards. The load bearing structures may be constructed by using Stone, Brick or Block Masonry Construction and these load bearing structures constructed by using stones, bricks or concrete blocks and we have Cavity Masonry Construction and Reinforced or Non-Reinforced Masonry Construction. This construction is adopted where hard strata is available. All conventional brickwork buildings are termed as load bearing structures. Such buildings consist of longitudinal and cross walls or partition walls. Both these walls carry the weight of roof or floor slab over it. The longitudinal walls here, carries the vertical loading in addition to the horizontal forces due to the earthquake or wind to the wall surface. There are no columns in such buildings and the cross walls and partition walls supply in plane lateral stiffness and stability to resist wind and earthquake forces. Load transfer Slab wall Foundation Lecture Number: 04 Topics to cover: Types of constructions - Framed structures FRAMED STRUCTURES: The frames structures are the one which consist of a column, beam, slab and walls. Such structures are used in multi-storied buildings. In a framed structure other than beams and columns Lecture Notes Page | 6  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) we also have flooring, bracing system and connections. The vertical or gravity load carrying system of a multi storied building consist of a system of vertical columns interconnected by horizontal beams which supports the floor and roofing. The resistance to lateral load is provided by the bracings or shear walls or by rigid frame action between the beam and column. In this the load is transferred from the slab to beam to column to foundation. When the beam and column shown here are connected as simple beam connections, the frame would have practically no resistance to the lateral forces and become geometrically unstable. The frame would laterally deflect as shown in figure even under a small lateral load. One of the three types of structural system may be used to resist the lateral load and limit the lateral displacement (drift) within acceptable range. (a) Rigid frames (b) shear walls (c)Braced-frames (a)Rigid frames Rigidly jointed frames have moment resisting connections between beams and column. A typical rigid frame is shown. It may be economically used to provide lateral resistance to low rise buildings. These are mostly used for steel structures. The rigid connection between column and horizontal beam is achieved by welding and bolting the two. By rigid joint it is meant that the original right angle between the centre-line of vertical and horizontal members remain the same even after lateral displacement. (b) shear walls In multi-storied buildings, the lateral loads are assumed to be concentrated at the floor levels. The rigid floors spread these forces to the columns or walls in the building. Specially designed reinforced concrete walls parallel to the direction of loads are used to resist the lateral loads caused by wind or earthquake by acting as deep cantilever beams fixed at foundation. These elements are called “shear walls”. (c) Braced frames In framed structures, to resist the lateral displacement, the simplest method is to provide diagonal bracing or x-(cross) bracings. This is only possible in steel framed building usually the x-bracing brings hinderance in placing of windows. However, k brace and knee brace may serve the purpose. Based on connection between beam and columns, the framed structures may be classified as follows: (i) simple connections (ii) Rigid connections (iii) Semi-rigid connections Load transfer Lecture Notes Page | 7  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) slab Beam Column Foundation Simple connections: Here the ends of beam behave as a simply supported beam and the ends rotate freely. Such a connection transfers shear and axial force between the connecting members but does not transfer the bending moment. Rigid connections: Such a connection between beam and a column is so detailed and constructed that the joint is monolithic and the angle between centre line of beam and column before deformation remains the same even after deformation. Such a connection transfers shear, axial force and bending moment from the beam to the columns. Rigid connections between R.C.C beams and columns is also possible. This can be achieved by providing the adequate reinforcement in the joint to take care of bending moment, shear and axial force developed at that joint. Semi-rigid connection: Due to flexibility of the joint some relative rotation between the beam and column occurs. When this is substantial, the joints are designed as semirigid. These connections are designed to transmit full shear and a fraction of the rigid joint bending moment. Lecture Number: 05 Topics to cover: Types of constructions - Composite Structure. COMPOSITE STRUCTURES: The composite structures are the one which is the combination of load bearing and framed structured so that we get the advantage of both the structures. In this type, external walls are load bearing type and internal supports are in the form of a column. Lecture Notes Page | 8  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Roofs and floors are supported by load-bearing walls and internal columns. The design and constructed of this type of structure may become difficult and complicated. When a structure has elements of steel and concrete that resist loads by a joint action (that is by pooling their respective strengths) it is called a composite structure. The composite structure is generally adopted for industrial sheds or warehouse where spans are very large. Usually, modern structures use members of steel or concrete they occur together in a building frame like concrete slab resting on steel beams but they resist load independently on each other. These are not composite structures. when a structure has elements of steel and concrete that resist load by a joint action it is called a composite structure. Lecture Number: 06 Topics to cover: Building components - Functions of building components 1.1 Building Components: The building components is nothing but a part of a building which consist of a wall, beam, column, slab, foundation, plinth beam etc., The construction is to be carried out by using team members like owner, engineer and contractor and workers. The team is formed to cooperatively plan, design and execute a particular building project. The building components are divided into two: Sub structure Super structure Sub structures: The lower most part of a building or bridge is called as “Sub-structure” which rests on foundation resting on ground. The components of a sub-structure are: (i) Foundation (ii) plinth in case of a building. In case of bridge, it may be ✓ Pier ✓ Abutment ✓ Foundation Foundation: Lecture Notes Page | 9  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Foundation is the part of the building which supports the super structure of a building and transmits the load directly to the soil i.e., Foundation is the lowest part of the building structure rested on soil below ground level. Its main function is to distribute the load evenly and safely to the ground. In framed structures footings are generally used as foundations to support the structural load of the building. The types of foundation are as follows: 1. Shallow foundation Individual footing or isolated footing Combined footing Strip foundation Raft or mat foundation 2. Deep Foundation Pile foundation Pier foundation Caissons foundation These are types of foundation and the types will be explained detailed in chapter 04. Function of foundation: To distribute the loads and to provide levelled surface. Stability against sliding and overturning. To minimize the differential settlement. Minimize distress against soil movement. Lecture Number: 07 Topics to cover: Building components - Foundation and plinth Plinth beam: Plinth beam is a reinforced concrete beam constructed between the wall and its foundation. Plinth beam is provided to prevent the extension or propagation of cracks from the foundation into the wall above when the foundation suffers from settlement. PURPOSE OF PLINTH: Lecture Notes Page | 10  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) The weightage of the superstructure is transferred to the foundation through the plinth. The plinth walls protect the building from rain and moisture. The top of the plinth is kept sufficiently above the flood level or rain water level so that water may not enter into the house. The flooring in the building is kept in level with the top of the plinth. The damp proof course is constructed over the top of the plinth walls, just below the superstructure walls. The damp proof course protects the superstructure wall from moisture rising from the ground through plinth walls. In case of bridges, (i) Pier: It supports the weight of the bridge and transfers it to the ground or suitable stratum under the river bed. It is constructed of brickwork, stone masonry or reinforced cement concrete. (ii) Abutment: Like pier, abutment is also part of the substructure, it supports the weight of the bridge. Abutment lies on either banks of a river or waterway. Abutment transfers the weight of the bridge to the suitable stratum. It is also constructed of brick or stone masonry, plain or reinforced cement concrete. (iii) Foundation: Here also the foundation for bridge is provided under the pier of abutment. The foundation may be open type foundation in case bridges otherwise it may be pile or well foundation. Bridge foundations are made of brickwork or reinforced cement concrete or piles made of steel or wood. Lecture Number: 08 Topics to cover: Building components - Super structures Super-structure: Lecture Notes Page | 11  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) It is the upper part of any structure, building or bridge. The various components of super- structures are: 1. Walls 2. Sills 3. Lintel 4. Doors and windows 5. Floors 6. Stairs and steps 7. Roofs and trusses 8. Beams 9. Columns 10. Parapet 11. Chhajja or sunshade (i) Walls: Walls are constructed to make rooms for living. Walls carry the weightage of roof or floor slab and transfers it to the foundation through the plinth walls. Walls are made of solid burnt clay bricks, hollow burnt clay bricks, stone blocks and concrete blocks. The walls may be: Load bearing walls Partition walls Cavity walls (two skinned walls) Panelled walls (combination of walls and piers) (ii) Sills: It is a thin slab of stone, wood or cement concrete provided at the foot of a door or below the bottom choukhat (frame) of a window. In a building, sills are provided in the form of a thin concrete member about 25mm thick, under the superstructure walls over the plinth. Sills made of properly proportioned thin concrete layer with suitable water proofing compound, may serve the purpose of protecting the moisture rising form the foundation to the superstructure walls. (iii) Lintel: Lintel in the form of thin slab are usually provided over opening of doors, window or verandah openings to transfer to the load of walls etc., above the lintel to the side walls. Lintel may be of wood, stone-slab, reinforced brickwork, reinforced concrete and rolled steel sections like I- beam or channels. (iv) Door and windows: Lecture Notes Page | 12  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Doors are usually provided to act as a means of communication from one room to another. Windows in buildings are provided to serve as a means for entry of light, air and proper ventilation. The doors and windows are made of wood, steel, plastic and poly vinyle chloride. (v) Floors: The bottom surface of a room or verandah on which one can walk and on which furniture, etc., are kept are called floors. (vi) Stair and steps: Stair which is housed in a staircase provides a vertical means of communicating from one floor of a building to another floor. A stair consists of a series of interconnected steps. Each step has a rise of about 150mm and tread (or horizontal going, a length equal to 250 to 280mm). A few steps, 4 to 5 in numbers are also provided to connect the ground level to the ground floor near the plinth. (vii) Roofs and trusses: Roof provides cover to rooms, to protect the inhabitants of the room from sun, rain, snow and wind. Roofs may be: (1) sloped roof (2) Flat roof (3) Trussed roof (1) Sloped roof They are slightly cheaper than flat roofs. Slope is given to the roof for quick drainage of rain water. In snowy areas, more slope is given to the roof for easy flow of snow. Sloped roof may be made of corrugated galvanized iron sheeting, asbestos cement sheet etc., These sheets are supported on steel or timber frame. The roof sheeting are properly fixed to the supporting frames and also the supporting members are properly anchored to the supporting walls to take care of the uplift pressure due to wind. (2) Flat roof These may be made of reinforced cement concrete slab. To protect the roof slab from the heat of the sun, insulation layer in the form of lime concrete terracing or other insulating medium is provided over the slab. Proper slope given to the terracing to drains the accumulated rainwater on the roof. Roofs can also be made, using wooden beams and burghas. Brick tiles are put over these and lime terracing is done on the tiles. (3) Trussed roof For large rooms or in workshop, trussed roofs are provided. Trusses are steel frames mostly interconnected triangle these are triangular or rectangular in elevation. The trusses are supported on walls, the roof usually consists of slope roof made of corrugated iron sheeting or asbestos sheet properly anchored to the purlin which is fixed to the trusses. Lecture Notes Page | 13  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Steel trusses are also used for the super structures of the bridges. Here two trusses on either side of the roadway carries the weight of road and the moving traffic on it. (viii) Beams Beams are horizontal slender members in a building, these are required to support the load of roof or floor. Beams are usually made of timber, rolled steel section or reinforced cement concrete (R.C.C). The timber and R.C.C beams are rectangular in section where as rolled steel beams maybe I section or fabricated steel sections. Timber beams are used in beam-burgha roof and also in timber flooring. In case of bigger rooms/ halls where the thickness of single R.C.C slab becomes more, beam and slab construction roof or floor are constructed. The rectangle R.C.C beams runs along the shorter span of the hall and the R.C.C slab which is cast monolithic with the beam spans at right angles to the beam. (ix) columns Columns are slender or short vertical members of a building. Columns may be made of timber, steel or R.C.C columns usually carry vertical loads. In some situations like columns in a framed building, these are subjected to bending moment in addition to the vertical load. (x) parapets Parapets are basically small height wall provided along all the boundary of the open terrace on the roof. It is constructed above the roof slab bearing on the main superstructure wall. The thickness of parapet is less than the main wall. The maximum height is limited to about less than a metre. Parapet is very useful and acts to protect the kids and onlookers on the open terrace. When the height of the parapet is more than a metre, it has to be reinforced of take care of the horizontal forces. Reinforcement may be in the form of brick pilasters located at 1.5 metres centre to centre. The pilasters are to be reinforced by providing vertical steel bars either in the brick masonry or in the R.C.C pockets. (xi) chajja or sunshade Chajja or sunshade is a horizontal member of a building, usually 50mm to 75mm thick, made of R.C.C. It is provided over window or verandah opening projecting outward from lintel level to a distance about 600 to 800mm. sometimes, chajja may be cast together with R.C.C lintel. The purpose providing chajja is usually protection of inside of room and verandah from rain, it also creates shade in sun, that is why the name sunshade Lecture Notes Page | 14  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Building Construction and Construction Materials UNIT 2 NATURAL AND ARTIFICIAL CONSTRUCTION MATERIALS Unit Content: Introduction Good building stones and its characteristics Timber, sand, Asphalt, bitumen, tar its properties and uses Bricks and its constituents – Modular, standard etc., Course Outcome CO201.1: Identify relevant construction materials. (CO) Covered for CO201.2: Identify relevant natural constructional this unit: materials. Number Lectures planned in Teaching TWELVE Plan: Reference: Building construction by Foundation Publishing by S N P Shrivastava Lecture Notes Page | 15  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 09 Topics to cover: Requirements of good building stone, General characteristics of stone Natural construction material are the one which naturally given as a god’s gift in which no human work is there like sand, rock etc., Artificial construction material are which are the materials manufactured by human beings like brick, tiles, concrete, Metals, glass, plastic, rubber, paint etc., Building Materials: Masonry may be defined as any construction using building units like bricks, stone or concrete blocks bonded together with mortar to make walls. Masonry usually are executed with the help of masons. Masonry materials may be ❑ Building Stones ❑ Bricks ❑ Mortars ❑ Lime ❑ Cement Good building stone: Stone has been one of the oldest materials of construction. Stones are heavy and requires lot of effort in shaping and bringing it for use in construction. For this reason, stones are used in areas where it is easily available. In other areas brick masonry are used where stone masonry becomes costly. Lecture Notes Page | 16  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) However, everywhere stones are used for making floor, in roadwork and also stone aggregates used for making concrete. In important buildings stones are also used for artistic ornamentation. Stones are derived from rocks. 2.1 REQUIREMENT OF GOOD BUILDING STONE: The following characteristics are looked into while selecting stone for use in a building o Appearance o General structure o Weight o Strength o Hardness o Toughness o Ease in working o Water absorption and porosity o Seasoning of stone o Weathering o Fire resistance The above will be discussed one by one as follows: (1) Appearance Stones used in exterior faces of building should look good and its colour should match with building around. Light colour stones are good in appearance, it should not contain any spot. In sedimentary rocks, presence of red and brown colour spot shows the presence of iron and should be avoided. (2) General structure When broken, the inner part should compact grain and uniform in texture and colour. There should not be any hollowness or softness inside. The surface of stone has mainly three types (a) Unstratified sometimes called crystalline structured rocks, (b) stratified stones and (c) Foliated structures (a) Unstratified crystalline structured rocks: All rocks obtained from igneous intrusion has unstratified structure. Its structure may be crystalline or amorphous which depend on the cooling rate of magma. Stones of this type are useful for building construction. (b) Stratified stones: Lecture Notes Page | 17  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Stratified rocks have a structure made of thin layers. The basic rock disintegrates due to wind and rain and flows with water, these gets deposited in thin layers in plains. Because of passage of time, under enormous pressure and heat, these layers gets stratified. The structure of such shows the plane of stratification which is the cleavage plane. (c) Foliated structure: The structure of metamorphic rocks has a bended texture called foliation (like the leaves of a book). These foliation breaks in a fixed direction. (3) weight: Stones having more weight are compact and less porous. They are useful for making irrigation structure like weir, barrage and dam etc., For making floor slab, stone used should be light. Usually, heavy stones has more strength. (4) strength: Should have good compressive and tensile strength. Stones obtained from the igneous rocks are stronger than the sedimentary rocks. Granite has an ultimate compressive strength of 80 to 150 N/mm2wheraeas sand stone has an ultimate compressive strength of about 50 to 70 N/mm2. (5) Hardness: Resistance to wear is a measure of hardness of stone. When there is more wear, hard stones should be used. Hardness more than 17 is good and less than 14 is considered poor. (6) Toughness: Toughness of any stone is its ability to absorb energy. In areas where, there is likely vibration and impact, more tough stone should be used. More tough stone is useful for road construction work. (7) Ease in working: It should be easy to cut and carve stones. But usually, the stones of such types are softer and has less hardness and toughness. (8) water absorption and porosity: Stones used on external surface of buildings should not be more porous. Absorption of water may disintegrate stone. A good quality stone should not absorb more than 5% of water. A stone absorbing more than 10% of water should not be used in constructions. (9) seasoning of stones: Freshly quarried stone contains moisture called quarry sap. If some carving etc. is to be done with freshly quarried stone. After carving and cutting stone should be left exposed so that moisture drives out. Otherwise also, the stones after quarrying is left exposed. It dried out and its durability increases. (10) weathering: Effect of season, sun and rain etc., causes weathering of stones. To know the effects of weathering, old building made of similar stone can be examined. If the old building has got Lecture Notes Page | 18  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) the same sharpness to its stone blocks used at corners and open surfaces has no effect of weathering, it can be said that such stones are good to weathering. (11) Fire resistance of stones: Stone disintegrates when comes in contact with fire and heat. The disintegration of stone depends on different thermal expansion of its mineral components. Trap and basalt have good fire resistance. Few igneous rocks and metamorphic rocks and metamorphic rocks like quartz and granite disintegrates at above 600°C temperature and turns into small pieces. Limestone is not affected up to 800°C but above the temperature calcium oxides disintegrate into carbon-dioxide. Sand stone is a good fire resistant. Characteristics of stone: Texture: A good building stone should have compact fine crystalline structure free from cavities, cracks or patches of soft or loose material Durability: A good building stone should be durable Hardness Appearance Fracture Specific gravity Seasoning Toughness index Appearance. For the face work of buildings this property is of extreme importance. From architectural point of view colour of the stone should be such as to go well with the surroundings. Lighter shades should be preferred to the darker ones as the latter are less durable, Red and the brown shades of sedimentary rocks are due to the presence of oxide of iron-which, if present in excess, is liable to disfigure the stone with rust stains and to disintegrate it. Stones should be of uniform colour and free from clay holes, bands or spots of color whatsoever. General Structure. Stone, when broken in a direction other than that of cleavage (if it exists), should not give dull appearance. It should show uniformity of texture. It must be either crystalline in structure of homogeneous and close-grained. It should be free from cavities, cracks or patches of soft or loose Lecture Notes Page | 19  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) material. For ornamental carvings it should be fine grained. Stratification (found in sedimen- tary rocks) should not be visible to naked eye except by difference in color. These can be easily split along their planes of stratification known as planes of cleavage, and are, therefore, useful for use in paving’s, floorings and roofing’s etc. Heaviness. Heavier varieties of stones are more compact, less porous and have greater specific gravities. For constructions in water, like weirs, barrages, dams, docks, harbours and for retaining walls the heavier varieties of stones are to be preferred. For construction of domes and for roof coverings and similar other usages the lighter varieties have to be used. Strength. In usual constructions the stones used are generally quite strong to withstand the forces likely to be encountered yet in case of construction where unusually bigger forces are likely to come the stone to be used should be tested for its strength. Stones of igneous class are generally stronger than those of the sedimentary class. Stones with compact fine crystalline texture are stronger. Hardness. It is the resistance of stone to abrasive forces caused by much wear and friction as in floors, pavements and aprons of bridges and weirs in rivers. Stones to be used at such places should be hard. Toughness. It is a measure of the impact that a stone can with stand. Stones used at places subject to vibrations of machinery and to moving loads should be tough. Stones used in the construction of roads should be hard and tough. Ease of working. The ease with which the stone can be worked upon i.e., cut, dressed, carved and moulded etc., is an important consideration from economy point of view. But this property is opposed to strength, durability and hardness. Lecture Notes Page | 20  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Porosity and absorption. More porous building stones are unsuitable for use in construction especially for exposed surfaces of structures. Rain water while coming down carries some acidic gases forming light acids which lodge on the surface of stones and soak in them. Very often it is driven in the pores of stones by the prevailing winds. Acids react with the constituents of stones causing them to crumble. In cold regions water freezes in the pores of stones. This water causes the disintegration of stones because of its increase in volume on freezing. Stones should as such be tested for porosity and care should be taken to use more porous stones only at places where they are not likely to encounter frost, rain or moisture in any other form. Seasoning. All freshly quarried stones contain a certain amount of moisture known as quarry sap, which makes them soft and easier to work upon. As such all work such as dressing, carving and moulding etc, should be done as early after quarrying as possible. Stones become considerably harder on seasoning. After quarrying, when all the work has been done upon stones, they should be left to season under sheds having no walls so as to permit free circulation of air. Sheds protect them from rains. A period of 6-12 months is generally enough for proper seasoning. Dressed faces should not be disturbed after seasoning as the crystalline film left by the quarry sap on evaporation weathers much better than the actual face of stone left after removal of that film. Weathering. It is the extent to which the face of a stone resists the action of weather. The best way of knowing the weathering properties of a particular stone is to inspect ancient buildings made with the same quality of stone possibly in the nearby place or at a place having similar atmospheric conditions. Inspection of an old face of some quarry could also be informative. If sharp edges and corners are preserved on an old building particularly on the faces exposed to rains and prevailing winds and on which sunlight does not play and if the chisel marks on such faces are distinctly visible then that variety of stone has good weathering qualities. Stones with good weathering properties only should be used in the construction of important buildings. Resistance to fire. To be fire-resistant stones should be free from calcium carbonate and oxide of iron and be not composed of minerals with differing co-efficient of thermal expansion. Lecture Notes Page | 21  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 10 Topics to cover: Quarrying of stone QUARRYING OF STONES: The place from where good stones is taken out from solid rock formation is known as quarry. Quarrying is the process of taking out stones from the quarry by way of excavating, heating or burning or by blasting. Usually, the quarries are located at height. In selecting the site for quarrying stones, the following points should be considered. (i) Labour must be available near the site. (ii) The quarrying site must be connected by roads and railways. (iii) water and electricity should be available railways. (iv) If explosives are used for quarrying, permanent structure should not be built near the quarry site. (v) There should be provision for drainage of rain water near the site. (vi) There should be ample space around quarry for stacking quarries stones, dressing of stones and keeping small garbage of stones. (vii) The site where quarrying is to be done should be open. Quarrying methods: The following are few of the quarrying methods Excavation method Wedging method Heating or burning method Blasting method Excavation method: Quarrying methods are classified differently. It is convenient to divide them under two main headings, namely, quarrying without blasting and quarrying by blasting. Quarrying of Stones Without Blasting: In these methods, blocks of rocks are broken loose from their natural outcrops by men using hand tools or special purpose channelling machines. No explosive material is used at any stage in this method of quarrying of stones. Soft rocks and also those rocks which have layered structure are easily quarried by these methods. Lecture Notes Page | 22  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) As a first step, the loose cover of soil over the rock (the over-burden) is first removed and the rock surface is cleared. It is then systematically broken into blocks of desired sizes either by driving wedges or by cutting channels. The Wedge Method of Quarrying: It is consisting of digging a few holes at carefully selected places on the rock. These holes are dug either manually using chisels and hammers by the skilled workers. Or, in major quarrying, these holes may be drilled by special machines called hammer drills. Once the hole is ready, a steel wedge is inserted in between two steel strips or feathers. This is done with all the holes drilled in a sequence. Such firmly inserted wedges are then struck with a hammer almost simultaneously. This process develops cracks along the lines joining the holes. After that, long iron bars are inserted in the holes and cracks, and then the blocks of the rocks are pushed forward onto the free face of a quarry. Blasting: In this method, the explosives are used to convert rocks into small pieces of stones. This method is used when stone to be excavated is of very hard variety and it has no cracks or fissures. Moreover, if stone is to be excavated on very large scale, blasting method will have to be adopted. No definite size blocks can be excavated by this method. After blasting, the excavated stone is sorted out in different sizes and categories. Explosives such as blasting powder, blasting cotton, dynamite and cordite are used. The operations involved are boring, charging, tamping and fining. Lecture Notes Page | 23  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Heating: Heating is most suitable for quarrying small, thin and regular blocks of stones from rocks, such as granite and gneiss. A heap of fuel is piled and Fred on the surface of rock in small area. The two consecutive layers of the rocks separate because of uneven expansion of the two layers. The loosened rock portions arc broken into pieces of desired size and are removed with the help of pick- axes and crowbars. Stone blocks so obtained are very suitable for coarse rubble masonry. Sometimes, intermediate layers are to be separated from the top and bottom layers. In such a case, the intermediate layer is healed electrically and the expansion separates it from the other two. Lecture Number: 11 Topics to cover: dressing methods and tools for stone. DRESSING OF STONE: Dressing of stones means preparation of the surface of the store to obtain plain edges or to obtain stones of required shape and size. Dressing of stone is an ancient art of India. Well-dressed stone blocks or pieces requires thin mortar joint in stone masonry. They provide good appearance on walls. Dressing is more important in making ornamental work in building. Dressing is done either by hand or machine depending on the type of stone. Types of hand dressing: Recommendations for hand dressing of building stone is described in IS:1129-1972. Few types of hand dressing described in the I.S. code is o Pitched faced dressing o Hammer dressing o Rock facing o Rough tooling Pitched faced dressing: Stone as received from the quarry, shall be dressed along the edges of its face by means of masons hammer and the pitching tool. The edges of a pitch faced dressed stone shall be level and shall be in the same plane absolutely square with the bed of the stone. Superfluous stone on the face shall be allowed to remain there and left in the form of a natural rounded cobble stone. The minimum width of pitched faced dressing round the four edges of the face of stone shall be 25mm. Lecture Notes Page | 24  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Hammer dressing: All the sharp and irregular corner of the stone obtained by blasting or splitting shall be knocked off by using the flat face of a spalling hammer with the pointed end of the hammer, the surface shall been be dressed. A hammer dressed stone shall have no sharp and irregular edges and shall have a comparative even surface so as to fit well in masonry. Appearance of hammer dressed stone is shown. Bushing on the face shall not be more than 40mm on exposed face. Rock face dressing: All the sharp and irregular corner of the freshly quarried shall be knocked off by using flat face of a scrabble hammer. The exposed face shall then be dressed as shown. A stone which has been dressed in this manner shall have an 25mm wide chisel mark at the four edges. All the edges being at the same plane. Some of this type of rock faced dressed stones are used as corner stones in rubble masonry near plinth. Rough tooling: A rough tooled surface shall have a series of bands 4 to 5cm wide, more pr less parallel tool mark all over the surface. These marks may be either horizontal, vertical or at an angle. The dressed stone may have depression of 3mm. Rough tooled stones are used where regular plane faces required for masonry work. Lecture Notes Page | 25  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Tools for stone: ✓ Point chisel ✓ Tooth chisel (rake) ✓ The flat straight chisel ✓ A hammer, all of varying sizes and weights. ✓ Lecture Number: 12 Topics to cover: Structure of timber, general properties and uses of good timber TIMBER: Timber or wood is a versatile construction material since ages. Lecture Notes Page | 26  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Inspite of the use of other structural material our industry and construction depend on wood. Wood suitable for engineering application is called timber Structure of timber: The different elements constituting the structure of a tree are explained briefly below: 1. Pith or Medulla The innermost central portion that contains entire cellular tissue is called pith or medulla. 2. Heart Wood The annual rings that surround the pith are called as heartwood. This portion is dark in colour and it does not take part in the growth of a tree. This part forms the strongest and durable art of a tree. 3. Sapwood The few outer annual rings are called sapwood. This part of the tree is active in growth. 4. Cambium Layer The thin layer between the bark and sapwood is termed as cambium layer. This layer contains sap which is yet to be converted into the sapwood. 5. Medullary Rays These are vertical layers of cellular tissues and are thin radial lines from plinth to the cambium layer. 6. Bark Bark or cortex is the outermost cover or skin of the tree. It is further divided into the inner bark and outer bark. The layer covering the cambium layer is called inner bark. The outer skin which is the protective layer of the tree is called bark or cortex. Lecture Notes Page | 27  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Properties of timber: Followings are the physical and mechanical properties of timber Colour Appearance Hardness Specific Gravity Moisture Content Shrinkage and Swelling Strength Density Toughness Elasticity Warping Durability Strength Density Toughness Elasticity Warping Durability Lecture Number: 13 Topics to cover: Different methods of seasoning for preservation of timber METHODS OF SEASONING: Air seasoning: The process of removing moisture from timber before it is used and put into service by drying in air Lecture Notes Page | 28  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Artificial Seasoning of Timber Natural seasoning gives good results but takes more time. So, artificial seasoning of timber is developed nowadays. By artificial seasoning, timber is seasoned with in 4-5 days. Here also different methods of artificial seasoning are there and they are as follows. Seasoning by Boiling Chemical seasoning Kiln seasoning Electrical seasoning Seasoning by Boiling Seasoning of timber is also achieved by boiling it in water for 3 to 4 hours. After boiling timber is allowed to drying. For large quantity of timber boiling is difficult so, sometimes hot steam is passed through timber logs in enclosed room. It also gives good results. The boiling or steaming process develops the strength and elasticity of timber but economically it is of heavier cost. Chemical Seasoning In case of chemical seasoning, timber is stored in suitable salt solution for some time. The salt solution used has the tendency to absorb water from the timber. So, the moisture content is removed and then timber is allowed to drying. It affects the strength of the timber. Kiln Seasoning In this method timber is subjected to hot air in air tight chamber. The hot air circulates in between the timber logs and reduces the moisture content. The temperature inside the chamber is raised with the help of heating coils. When the required temperature is obtained Lecture Notes Page | 29  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) moisture content and relative humidity gets reduced and timber gets seasoned. Even though it is costly process it will give good results strength wise. Compartment kiln: A compartment kiln is a type of kiln used for the seasoning of timber. It consists of several compartments or chambers that are used to dry the timber at different stages of the process. The process of seasoning timber involves removing moisture from the wood in order to reduce its weight, prevent warping and cracking, and improve its overall quality. Compartment kilns are designed to facilitate this process by providing controlled environments in which the timber can be dried. The kiln operates by circulating hot air through the compartments, which gradually removes moisture from the timber. The temperature and humidity levels in each compartment are carefully controlled to ensure that the timber is dried at a consistent rate without being damaged. Compartment kilns are commonly used in the timber industry because they offer several advantages over other types of kilns. For example, they can be designed to accommodate large volumes of timber and can be used to dry a variety of different wood species. Lecture Notes Page | 30  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Progressive kiln: A progressive kiln is another type of kiln used for the seasoning of timber. Unlike compartment kilns, progressive kilns are continuous in operation and do not use separate compartments. In a progressive kiln, the timber is moved through a series of drying zones, each with its own temperature and humidity controls. The temperature and humidity levels are carefully monitored and adjusted as the timber progresses through the kiln, ensuring that it is dried at a consistent rate without being damaged. One of the advantages of progressive kilns is that they can be operated continuously, allowing for a more efficient and streamlined drying process. They also require less space than compartment kilns, making them a good option for smaller operations. However, progressive kilns may not be as effective as compartment kilns for drying certain types of wood, such as thicker or more dense species. In addition, the drying process in a progressive kiln may not be as consistent as in a compartment kiln, which can affect the quality of the final product. Lecture Notes Page | 31  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Electrical Seasoning In the method of electrical seasoning timber is subjected to high frequency alternating currents. The resistance of timber against electricity is measured at every interval of time. Lecture Number: 14 Topics to cover: Defects in timber DEFECTS IN TIMBER: There are various types of defects in timber as a construction material. These defects in timber can be due to natural forces, fungi, insects, and during seasoning and conversion. The followings are the five main types of defects in timber: 1. Defects due to Natural Forces 2. Defects due to Attack by Insects 3. Defects due to Fungi 4. Defects due to Defective Seasoning 5. Defects due to Defective Conversion Wind Cracks in Timber If the wood is exposed continuously to the high-speed winds, the outer surface shrinks and forms crack externally, which are called wind cracks. Shakes in Timber Shakes are nothing but cracks which separate the wood fibres partly or completely. Different shakes are formed in different conditions as follows: Cup shakes are formed due to the non-uniform growth of a tree or excessive bending by cyclones or winds. In this case, the shakes develop between annual rings and separate them partly. Heart shakes, the other type of shakes which develop in maturity approaching trees whose inner part is under shrinkage. The shake spread from pith to sapwood following the directions of medullary rays. Lecture Notes Page | 32  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Ring shakes are similar to cup shakes, but they completely separate the annual rings. Star shakes are formed due to extreme heat or severe frost action. They develop wider cracks on the outside of timber from bark to the sapwood. Radial shakes are developed radially from pith to the bark. Twisted Fibres in Timbers When the tree in its younger age is exposed to high-speed winds, the fibres of wood gets twisted. This type of wood is not suitable for sawing. So, this can be used for making poles, posts, etc. Upsets Upsets, a defect of timber in which the fibres of the wood are crushed and compressed by fast blowing winds or inappropriate chopping of trees. Rind Galls Rind galls are curved swellings of trees which are formed at a point where a branch of the tress is improperly removed or fell down. Burls Burls are uneven projections on the body of the tree during its growth. These are mainly due to the effect of shocks and injuries received by the tree during its young age. Lecture Notes Page | 33  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Knots in Timber The central part or stem of a tree is majorly used in the conversion of timber. Branches from the stem are removed, and the whole rounded stem is taken. But the base of branches forms a mark on the stem, which results in dark-coloured stains on the surface after conversion. This dark-coloured stains are due to the continuity of wood fibres. These dark-coloured rings are known as knots. Sap Stain in Timber When the moisture content in the timber is more than 25%, some types of fungi attack the sapwood and make it discoloured. This type of defect is known as a sap stain. Defects in Timber During Seasoning 1. Bow 2. Cup 3. Check 4. Split 5. Twist 6. Honeycombing 7. Case hardening 8. Collapse 9. Warp 10. Radial shakes Lecture Notes Page | 34  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) 1. Bow When the converted timber is stored for a longer time, some timber planks may have a curve along its length, which is known as Bow. Cup If the timber planks curve along its width, then it is called Cupping of timber. Check Check is the formation of a crack in the wood, which will separate the wood fibres. They form due to over seasoning of timber. Twist Twist forms when the timber piece is distorted spirally along its length. It looks like a propeller blade after twisting. Honeycombing Honey combing occurs in the inner part of the timber, which cannot be identified by just seeing. It is mainly due to stresses developed during the drying of timber. Lecture Notes Page | 35  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Defects in Timber During Conversion 1. Diagonal grain 2. Torn grain 3. Chip mark 4. Wane 1. Diagonal Grain Defect in Timber During the conversion of timber, different cutting saws are used. The cutting should be done properly. If there is any improper cutting by the saw, then a diagonal grain will appear. 2. Torn Grain In the conversion, many tools are used. If any of the tools or any other heavy things are dropped accidentally on the finished surface of timber it will cause small depression, which is called torn grain. 3. Chip Mark When the timber is cut through the planning machine, the parts of the machine may form chip marks on it. Usually, they are indicated by chips on the finished surface. Defects in timber due to Insects 1. Termites 2. Beetles 3. Marine borers 1. Termites in Timber Termites also known as white ants which form a colony inside the timber and eat the core part of the timber rapidly. They do not disturb the outer layer of timber, so one cannot identify their presence. The trees in tropical and sub-tropical regions are mostly affected by these termites. However, some trees like teak, Sal, etc. cannot be attacked by termites because of the presence of termite preventing chemicals in their cellulose part. 2. Beetles in Timber Beetles are a type of insects that destroy the sapwood of the tree and make a tunnel-like hole from the bark. Usually, the diameter of the hole is around 2 mm. They convert sapwood into powder form, and larvae of these beetles use these holes. Almost all hardwood trees can be prone to damage by these beetles. Lecture Notes Page | 36  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 15 Topics to cover: Asphalt, bitumen and tar used in construction, properties and uses. BITUMEN: Bitumen, also known as asphalt in the United States, is a substance produced through the distillation of crude oil that is known for its waterproofing and adhesive properties. Bitumen production through distillation removes lighter crude oil components, such as gasoline and diesel, leaving the “heavier” bitumen behind. Properties: 1. Adhesion 2. Resistance to Water 3. Hardness 4. Viscosity and Flow 5. Softening Point 6. Ductility 7. Specific Gravity 8. Durability 9. Versatility 10. Economical 11. Strength ASPHALT: Asphalt is a mixture of aggregates, binder and filler, used for constructing and maintaining roads, parking areas, railway tracks, ports, airport runways, bicycle lanes, sidewalks and also play- and sport areas. Aggregates used for asphalt mixtures could be crushed rock, sand, gravel or slags. Properties: Waterproof Property. Asphalt is a water-repellent material with a lightweight structure that does not dissolve in water. Viscosity. Plasticity. Temperature Sensitivity. Lecture Notes Page | 37  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) The Stability of Asphalt in the Atmosphere TAR: Asphalt, Bitumen and Tar are hydrocarbons, termed as bituminous materials. Asphalt and bitumen are petroleum products, whereas tar is a dark coloured product collected from destructive distillation of organic substances like coal, wood or bituminous rocks. Properties: Coal tar is black in color. It’s a semi-solid and semi-liquid in nature and is less permeable. Its density is very thick and It has a peculiar smell. Tar is insoluble in nature which means that it can’t dissolve in water. It has a boiling point of two hundred to two hundred and fifty-degree celsius. Its a fuel resistant and has more temperature susceptible than asphalt cement. Lecture Number: 16 Topics to cover: Properties of sand and uses. Properties of sand and uses: Sand is a mixture of small grains of rock and granular materials which is mainly defined by size, being finer than gravel and coarser than silt. And ranging in size from 0.06 mm to 2 mm. Followings are the desirable properties of sand: ❑ Should be completely inert. (i.e., should not have any chemical activity). ❑ Grains should be sharp, strong & angular. ❑ Should not contain any hygroscopic salts (i.e., CaCl2, MgCl2, etc.). ❑ Should not contain clay & silt; usually 3-4% clay & silt is ordinarily permitted for practical reasons. ❑ There should be no organic matter. USES: ❑ The most prolific user of sand is the construction industry where it is almost vital for almost every aspect of a building project. ❑ Sand is used in everything from cement and concrete to plastering, roofing, grouting and paint. Lecture Notes Page | 38  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) ❑ It’s even used to help defend buildings from flooding when its in sandbags. Lecture Number: 17 Topics to cover: Classification of coarse aggregate according to size. Classification of coarse aggregate according to size: When the aggregate is sieved through 4.75mm sieve, the aggregate retained is called coarse aggregate. Gravel, cobble and boulders come under this category. The maximum size aggregate used may be dependent upon some conditions. In general, 40mm size aggregate used for normal strengths, and 20mm size is used for high strength concrete. the size range of various coarse aggregates given below. Coarse aggregate Size Fine gravel 4mm – 8mm Medium gravel 8mm – 16mm Coarse gravel 16mm – 64mm Cobbles 64mm – 256mm Lecture Notes Page | 39  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Boulders >256mm CLASSIFICATION OF COARSE AGGREGATE ACCORDING TO SHAPE Rounded aggregates Irregular or partly rounded aggregates Angular aggregates Flaky aggregates Elongated aggregates Flaky and elongated aggregates Lecture Number: 18 Topics to cover: Constituents of brick earth, Conventional / Traditional bricks Constituents of brick earth: o Bricks are the most commonly used construction material. Bricks are prepared by moulding clay in rectangular blocks of uniform size and then drying and burning these blocks. In order to get a good quality brick, the brick earth should contain the following constituents. o Silica o Alumina o Lime o Iron oxide o Magnesia SILICA o Brick earth should contain about 50 to 60 % of silica. o It is responsible for preventing cracking, shrinking and warping of raw bricks. o It also affects the durability of bricks. o If present in excess, then it destroys the cohesion between particles and the brick becomes brittle. ALUMINA o Good brick earth should contain about 20% to 30% of alumina. Lecture Notes Page | 40  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) o It is responsible for plasticity characteristic of earth, which is important in moulding operation. o If present in excess, then the raw brick shrinks and warp during drying. LIME o The percentage of lime should be in the range of 5% to 10% in a good brick earth. o It prevents shrinkage of bricks on drying. o It causes silica in clay to melt on burning and thus helps to bind it. o Excess of lime causes the brick to melt and brick loses its shape. IRON OXIDE o A good brick earth should contain about 5% to 7% of iron oxide. o It gives red colour to the bricks. o It improves im-permeability and durability. o It gives strength and hardness. o If present in excess, then the colour of brick becomes dark blue or blackish. o If the quantity of iron oxide is comparatively less, the brick becomes yellowish in colour. MAGNESIA o Good brick earth should contain less a small quantity of magnesia about1%) o Magnesium in brick earth imparts yellow tint to the brick. o It is responsible for reducing shrinkage. o Excess of magnesia leads to the decay of bricks. Conventional / Traditional bricks: Traditional Bricks are those which have not been standardized in size. The dimensions of traditional bricks vary from place to place. The length varies from 20 to 25 cm, width varies from 10 to 13 cm and thickness varies from 5 cm to 7.5 cm. Conventional/ traditional size of brick in mm: - conventional size of brick specification (Length × breadth × height), the length varies from 200 to 250 mm, width varies from 100 to 130 mm and thickness varies from 50 mm to 75 mm. The commonly adopted nominal size of traditional/ conventional brick is 230 mm x 114 mm x 76 mm (9”x4 ½ “x3”) approximately. Standard size of brick used in India are two types: - 1) modular brick and 2) non modular brick. The standard modular size of common building brick specification (length × breadth × height) used in India shall be 190mm × 90mm × 90mm and 190mm × 90mm × 40mm and non – modular size of bricks like 230mm × 110mm × 70mm & 230mm × 110mm × 30mm may also be used. Lecture Notes Page | 41  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Indian Standard brick size Indian standard brick size: - Standard size of brick used in India are two types:- 1) modular brick and 2) non modular brick. Indian standard modular size of common building brick specification (length × breadth × height) used shall be 190mm × 90mm × 90mm and 190mm × 90mm × 40mm and non – modular size of bricks like 230mm × 110mm × 70mm & 230mm × 110mm × 30mm may also be used. Brick Shall be hand moulded or machine moulded and shall be made from suitable soil this will be free from cracks, flaws dust and nodules of free lime. Standard size of brick is hand moulded or machine moulded should have length 190mm, breadth 90mm and depth 90 mm or 70mm provided with a frog dimension 10 to 20mm deep on one of its flat sides. Bricks of 40mm height as well as those made by extrusion process may not be provided with frog. Standard size of brick in cm Standard size of brick in cm are following: - 1) modular brick size (l × b × h) – 19cm × 9cm × 9cm and 19cm × 9cm × 4cm and 2) non – modular size of bricks like 23cm × 11cm × 7cm & 23cm × 11cm × 3cm may also be used. 9cm & 7cm height of brick is provided with a frog dimension 1 to 2cm deep on one of its flat side, bricks of 4cm & 3cm height as well as those made by extrusion process may not be provided with frog. Standard size of brick in mm Standard size of brick in mm are following: - 1) modular brick size (l × b × h) – 190mm × 90mm × 90mm and 190mm × 90mm × 40mm and 2) non – modular size of bricks like 230mm × 110mm × 70mm & 230mm × 110mm × 30mm may also be used. 90mm & 70mm height of brick is provided with a frog dimension 10 to 20mm deep on one of its flat side,bricks of 40mm & 30mm height as well as those made by extrusion process may not be provided with frog. Standard size of brick in inches Standard size of brick in inches are following: - 1) modular brick size (l × b × h) – 7.5″ × 3.5″ × 3.5″ and 7.5″ × 3.5″ × 1.5″ and 2) non – modular size of bricks like 9″ × 4.3″ × 2.75″ & 9″ × 4.3″ × 1.18″ may also be used. 3.5″ & 2.75″ height of brick is provided with a frog Lecture Notes Page | 42  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) dimension 0.4″ to 0.8″ deep on one of its flat side,bricks of 1.5″ & 1.18″ height as well as those made by extrusion process may not be provided with frog. Lecture Number: 19 Topics to cover: Modular and Standard bricks, Special bricks –fly ash bricks, Modular and standard bricks: A modular brick has a set of nominals, specified and actual dimensions as referenced above. A non-modular brick has a set of specified and actual dimensions but does not have nominal dimensions. Brick is available in many sizes and are referred to by many different names, depending on region. The actual size of the standard modular brick as per Indian Standards is 19 cm × 9 cm × 9 cm. Standard size of modular brick Standard size of modular brick are following:- 1) 190mm × 90mm × 90mm (l×b ×h) – 90mm height brick provided with 10mm to 20mm deep frog on one of its flat side. 2) 190mm × 90mm × 40mm (l × b × h)- 40mm brick height may not be provided with frog. Nominal size of brick Nominal size of brick– when we add thickness of brick joint or cement mortar thickness in actual size of brick that is nominal size of brick, such that nominal size of brick = Actual size of brick + thickness of cement mortar, actual size of modular brick is 190mm × 90mm × 90mm, when we add 10mm thickness in which dimension we get nominal size of brick in mm as 200mm × 100mm × 100mm, in cm as 20cm × 10cm × 10cm and in inches as 9″ × 4″ × 4″. The common burnt clay bricks shall be classified on the basis of average compressive strength into different class designation like 35, 30, 25, 20, 17.5, 15, 12.5, 10, 7.5, 5 & 3.5 having compressive strength are 35 N/mm2, 30 N/mm2, 25 N/mm2, 20 N/mm2, 17.5 N/mm2, 15 N/mm2, 12.5 N/mm2, 10 N/mm2, 7.5 N/mm2, 5 N/mm2 and 3.5 N/mm2 respectively. Lecture Notes Page | 43  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Standard brick size and weight Standard brick size and weight: According to Indian practice the weight of standard size of brick is kept between 3- 3.5 kg, depending upon the class of brick, so that a mason can lift it by one hand and work full day. The width should be 4 to 5″ so that a mason can hold it using his fingers and thumb. What is called frog in brick size? An indent on one surface of longer side of brick is called Frog, the depth of Frog shall be 10–20 mm, and the size of shall be 10 X 40 X 10 cm. The purpose of providing frog is to hold the mortar. The side of frog is considered as Top surface. It is not provided in the 40 cm high bricks and extruded bricks. But practically to match with the beam width a brick or block of width 230 mm is used widely in construction industry. The 115 mm is considered for half brick. The size 230 mm X 110 mm X 110 mm or 230 mm X 110 mm X 75 mm is generally used in construction industry. Popular size of brick used in india Modular/ Metric Brick: nominal size 20 x 10 x 10 cm. This size is common in MP and only some other places where machine made bricks are available. English size: 23 x 11.5 x 7.5 cm or 9″ x 4.5″ x 3″ nominal size. This is the most popular size available in most parts of India. Bengal size: 25 x 12.5 x 7.5 cm size or 10″ x 5″ x 3″. This size is popular in in West Bengal and some parts adjoining West Bengal and North East. A few other sizes are also used in some localized areas. Basically, the size of a brick is governed by its weight, which should not be more than 3 Kg, so that a mason can lift it by one hand and work full day. The width should be 4 to 5″ so that a mason can hold it using his fingers and thumb. The ratios of length: breadth: thickness are so chosen that the bricks when laid in masonry make a pattern (or Bond) so that vertical joints do not come one above the other in alternate courses. Special bricks – fly ash bricks: Lecture Notes Page | 44  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Special bricks are specially shaped bricks that allow for a lot of creative shapes and architectural features. These include copings and capping, plinth headers, single and double bullnose, cant brick shapes we also supply prefabricated arches too. Fly ash bricks are hi-tech well-improved quality bricks used for construction of brick masonry structures. They are used as replacement for normal clay bricks and has better properties than it. Fly ash bricks competitive in comparison to the conventional clay bricks and provide enormous indirect benefits. Composition of Fly Ash Bricks The important compositions of fly ash bricks are: Fly ash Cement Sand Water Sources of Fly Ash 72% of India's power plants are coal based. These power stations generate nearly 40 million tons of fly ash annually. Fly ash contains Co2 emitted from Thermal power plants, industries using coal as a fuel emits unwanted ash and smoke from which fly ash is produced. In all the power plants and industries, they separate the fly ash by using the cyclone converter. This fly ash is then used as a raw material for manufacture of bricks. Nature of Pollution Caused by Fly Ash Fly ash causes severe pollution of air and water, and its disposal gobbles up large tracts of land. Well- planned programs for proper management of fly ash are therefore being undertaken to enhance the use of fly ash in various applications, so that our already perilously imbalanced environment can be protected Manufacture of Fly Ash Bricks The fly ash brick is nothing but a slow setting pozzolana cement mix. The process is same as making cement in cement factories whereas the clay and limestone are burnt with coal and gypsum. And it is mixed and ground to cement. In fly ash mix also the fly ash, which is burnt clay particles (oxides of clay) obtained from burning coal, which contains clay from the mines. When hydrated lime powder, gypsum are mixed and ground in a pan, the mixture gives a slow setting pozzolana cement. While the mix is pressed at low pressure at low moisture content in hydraulic machine, which is specially designed to give high pressure load Lecture Notes Page | 45  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) at a slow rate, in the order of 350kg/square inch. At this of rate of pressure and with holding the pressure for a desired time gives ultimate strength to fly ash bricks. Benefits of Fly Ash Bricks for Environment The increase in greenhouse gases, out of which CO2 is one of the major constituents, increases the global warming year after year, causing drought and floods. The total CO2 Emissions globally account for 24,960 million tons at 1990 levels. Cement and building materials industry is one of the major contributors. The CO2 emission is about ninety million tons out of cement and forty-nine million tons out of clay bricks production in India. As per the ongoing practices in India, each million clay bricks consume about 200 tons of coal (or any other fuel with equal quantity of thermal values) and emit around 270 tons of CO2. Fly ash bricks production in energy-free route saves the emissions totally, befitting the project to qualify under Clean Development Mechanism (CDM), as envisaged by Kyoto Protocol towards the welfare of Mother Earth. Lecture Number: 20 Topics to cover: Characteristics of good brick Characteristics of good brick: Bricks should be uniform in colour, size and shape. Standard size of brick should be maintained. They should be sound and compact. They should be free from cracks and other flaws such as air bubbles, stone nodules etc. with sharp and square edges. Bricks should not absorb more than 1⁄5 of their own weight of water when immersed in water for 24 hours (15% to 20% of dry weight). The compressive strength of bricks should be in range of 2000 to 5000 psi (15 to 35 MPa). Salt attack hampers the durability of brick. The presence of excess soluble salts in brick also causes efflorescence. The percentage of soluble salts (sulphates of calcium, magnesium, sodium and potassium) should not exceed 2.5% in brunt bricks. Brick should not change in volume when wetted. Bricks should neither overburnt nor under-brunt. Lecture Notes Page | 46  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Generally, the weight per brick should be 6 lbs. and the unit weight should be less than 125 lbs. per cubic ft. The thermal conductivity of bricks should be low as it is desirable that the building built with them should be cool in summer and warm in winter. Bricks should be sound proof. Bricks should be non-inflammable and incombustible. Bricks should be free from lime pitting. Lecture Notes Page | 47  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Building Construction and Construction Materials UNIT 3 SPECIAL AND PROCESSED CONSTRUCTION MATERIALS Unit Content: Introduction Water proofing, Termite proofing Thermal and sound insulating materials Paints Course Outcome CO201.3: Select relevant special type of construction (CO) Covered for materials. this unit: Number Lectures planned in Teaching FOUR Plan: Reference: Building construction by Foundation Publishing by S N P Shrivastava Rangwala, S.C., Building Construction, Publishing, House, Anand Punmia B.C., and Jain A.K., Building Construction Lecture Notes Page | 48  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Lecture Number: 21 Topics to cover: Types of material and sustainability in construction works of materials - Water proofing Special and processed construction material are the material which is used for the protection of our building. Due to rain or leakages water will enter into the sub structure that will cause the building to get damage, to avoid that water proofing is provided. Similarly, to protect the building from termite or insect attack termite proofing is used. To protect the building from cracks paints is used. So special and processed materials will be like paint, distemper, varnish which went through some manufacturing process which is used for the protection of our building. 3.1 Types of material and sustainability in construction works of materials: WATER PROOFING: Waterproofing in building construction is the process of making a structure water- resistant or impervious to the ingress of water. Waterproofing is essential as it prevents water from penetrating buildings and helps to keep the interior areas dry. It is essential to waterproof your house. Interior areas of our house must be kept dry from roof to basement. Water infiltration can lead to damages such as insect infestation, mold and in worst cases building failures. Waterproofing the house before construction will avoid these problems. Materials for water proofing: ❑ Water proofing with bituminous sheets ❑ Water proofing by elastomeric paints ❑ Water proofing by epoxy ❑ Integral waterproofing compound Water proofing with bituminous sheets Bituminous sheets made using vegetable or animal fibre materials. Nowadays it is replaced by sheets made of inorganic material like fibre glass and plastics. Disadvantages of the bituminous system is the problem of renewal. Water proofing by elastomeric paints The thickness of these paint coating is about 0.5 to 0.75mm. Preferably applied using a roller or it can also be sprayed or brushed. Lecture Notes Page | 49  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Few types of these paints are ❖ Acrylic based paint ❖ Polyurethane based paint ❖ Poly vinyl acetate co-polymer-based paint ❖ Polymerised elastomeric bitumen Water proofing by epoxy ❖ Epoxy, two phase system or araldite and hardener with or without filling materials are used for repairing of concrete as well as waterproofing of terraces. ❖ Two coats of epoxy mix consisting of Araldite GY 257 and hardener HY 840 in equal proportion by weight have been found to give good result as a waterproofing material. Integral waterproofing compound ❖ These are available in the market having the brand name of CICO, Impermo, Accoproof etc., ❖ These are available in powder or liquid form. ❖ These are added to cement mortar or cement concrete during mixing to reduce the permeability of the mix. Water proofing in wet areas: Washing areas like bathrooms toilet Veranda and balconies Upper floor of two storey building – Affect the slab, water dripping down Effective way to keep off this moisture penetration is to apply a coat of bitumen during the construction. Lecture Number: 22 Topics to cover: Termite proofing Termite proofing: ❑ Termite proofing is the treatment given to a building, to control or prevent the termite growth in the building. The termites enter into buildings through cracks, walls, pipes and floor joints etc. Once termites developed in the building area, it is very difficult and costly to finish. Woodwork is frequently attacked and damaged by termites, mostly by white ants that fed on wood and other cellulosic materials like textiles, paper and cardboard. Lecture Notes Page | 50  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Sometimes, white ants may also damage non-cellulosic materials like plastic, leather and rubber. Hence, it is essential to treat the building with termite-proofing to protect household things like furniture, cupboards, finishing’s, clothing and paper. Types of Termites: Based on the habitat, termites are of two types Ground-nesting termites Drywood termites Termite proofing materials: Chemicals for anti-termite treatment available in the market under the brand names Durmet that consist Chloropyrifos concentrate 1.0% by weight and Dursban TC. The other chemicals like Aldrin, DDT can prevent the growth of termites, but these chemicals pose significant health hazards for human beings However, many of these chemicals are now banned under IS code, and the following emulsifiable chemicals are recommended: Heptachlor concentrate: 0.5% by weight Chlorpyrifos concentrate: 1.0% by weight Chlordane concentrate: 1.0% by weight Pre construction treatment: Anti-termite treatment should start when the pits are ready to prevent the entry of subterranean termites into the buildings by creating a chemical barrier in the soil surrounding the construction premises. The various stages of anti-termite treatment carried out are as follows: 1. site clearance 2. Bottom and sides of trenches up to a height of 300 mm should be treated with Durmet solution at the rate of 5 litres per square metre of surface area. 3. The refilled earth in contact with walls and columns should be treated with anti-termite chemicals for a width of 300 mm. About 3 to 5 litres per linear metre of the vertical surface should be used. 4. 4) After filling the earth up to plinth level for flooring, 50 to 70 mm deep holes should be drilled at 150 mm grid pattern. Treat these holes with the chemical solution at the rate of about 5 litres per square metre area. 5. The junction of walls and floors should be treated at the rate of 15 litres per square metre of the wall surface. Lecture Notes Page | 51  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) 6. After the completion of construction, holes 300 mm deep should be drilled along the external perimeter of the building at an interval of 150 mm. The holes should be filled with chemicals at the rate of 5 litres per metre length. 7. Expansion joints and perimeters of pipes and conduits should also be treated with anti- termite chemicals. 8. Before installing windows and doors in contact with masonry should be coated with two layers of paint. Post construction treatment: If termite growth is found in any building, post-construction treatment is required for termite- proofing. Pressure pumps are used to ensure proper chemical penetration, and the procedures are described below: Outside walls around the building: If flagging concrete is present around the building, then holes of diameter 12 mm are drilled at distances of 300 mm and a chemical solution is pumped inside the holes. If there is no flagging concrete, then 500 mm deep holes are drilled at distances of 150 mm using iron rods and filled with chemicals. Soil under floor: For treating floor, walls, construction joints, cracks, etc.., holes of diameter 12mm are made 300 mm apart. These holes are pumped into soak the soil with a chemical solution of about 1 litre. Treatment at plinth level: The holes are drilled on both sides of the wall at plinth level at an angle of 45¬° and a distance of 300 mm from the centre. The chemical solution is pumped in and after they are sealed with cement mortar in proportion 1:2. For better protection from termites, structural barriers can be provided with concrete or with metal sheets. Concrete barriers are more durable than metal barriers as they are likely to fail due to corrosion or other damage. Concrete barriers can be of 50-75 mm thick concrete extending about 50-75 mm on both sides of the plinth. Termites have the potential to damage your building significantly. So, termite-proofing services are highly essential for any building to eliminate and dismantle termites attack and protect the wood interiors of the building. Lecture Number: 23 Topics to cover: Thermal and sound insulating materials Thermal and sound insulating materials: Lecture Notes Page | 52  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) Thermal Insulation: The process of insulating against transmission of heat. Heat Transfer: From WARM to COOL In buildings, where the ideal situation is to have a relatively stable temperature, two situations arise.  In winter; energy must be used to maintain a comfortable temperature. Without proper insulation heat is lost to the colder outside air.  In summer; temperatures are usually higher outside than inside, the building interior must be cooled to keep it comfortable. The less insulation that is used, the greater are the cost for air-conditioning. Kinds of thermal Insulation: All the materials that used to prevent heat losses are known as thermal insulation. There are 9 basics kinds; 1. Loose fill 2. Blankets 3. Batts 4. Structural insulation board 5. Slab or block insulation 6. Reflective insulation 7. Sprayed-on 8. Foamed-in place 9. Corrugated insulations 1. Loose Fill Usually it is bulky and can be divided into two main types; Fibrous Granular Fibrous type is made from mineral wool, rock, glass or slag wool, or vegetable fiber – usually wood fiber. Granular insulations are made from expanded minerals such as perlite and vermicullite or from ground vegetable matter such as granulated cork. 2. Blanket insulation Blanket insulation is made from fibrous material, such as mineral wool, wood fiber, cotton fiber, or animal hair, manufactured in the form of a mat. Mats are made in various thickness and cut in a variety of widths, sometimes with a paper cover. 3. Batts They are similar in basic manufacture to blankets, but they are restricted as to length, usually being 1.2 m or less. Some are paper covered, some are made without a cover and fit between framing members by friction (see Figure 6.1). 4. Structural Framing Board It is made from a variety of substances, such as cane, wood and mineral fibers. It is used for exterior or interior sheating, insulating roof decking, roof insulating board, and interior finishing board. 5. Slab Insulation Slab or block insulation is made in rigid units, normally smaller in area than insulation board, through some of them may be made from two or more pieces of insulation board Lecture Notes Page | 53  BUILDING CONSTRUCTION AND CONSTRUCTION MATERIALS (2015301) cemented together to make a thick slab. It is made also from cork, shredded wood, and cement, mineral wool with binder, cellular glass, foamed concrete, foamed plastic, cellular hard rubber, concrete made with “perlite, vermicullite, expanded clay as aggregate” 6. Reflective Insulation They are composed of metallic or other special surfaces with or without some type of backing.Unlike others, reflective insulations rely on their surface characteristics, thickness of air space, temperature differences etc. for their insulating value. 7. Sprayed-On Insulation Produced by mixing some fibrous or cellular material with an adhesive and blowing the mixture on to the surface to be insulated. Areas that are difficult to be insulated are treated in this manner (shape, location, etc.). 8. Foamed-in Place Insulation Made from synthetic liquid resins. Two ingredients are used which, when mixed, produce a foam which solidifies to fill the space into which the mixture was introduced. 9. Corrugated Insulation Made from paper, corrugated or cemented into mult