SHOTS - BUILDING MATERIAL & BUILDING CONSTRUCTION

💥 Gypsum is a mechanically formed sedimentary rock. 

💥 Quartzite is a silicious rock. 

💥 Slate is formed by metamorphic action on shale. 

💥 Heavy stone is suitable for retaining wall. 

💥 Hard stone is suitable for rubble masonry. 

💥 Soft stones is suitable for ornamental work. 

💥 Quartzite has most weather resisting characteristics. 

💥 A good building stone should not absorb water more than 5%. 

💥 Compact sand stone has more fire resisting characteristics. 

💥 Weight test is conducted on a stone used in docks and harbours. 

💥 Granite stone is best suited for construction of piers and abutments. 

💥 Crushing strength of good building stone should be more than 100mpa. 

💥 Specific gravity of most of the building stone lies between 2.5 to 3. 

💥 Pith-annular rings-heartwood-sapwood - cambium layer-inner and outer bark. 

💥 Shisham is hard wood and offer maximum resistance to the white ants. 

💥 Star shakes-the radial splits which are wider on the outside of the log and narrow towards the pith. 

💥 Chir and deodar yields soft wood. 

💥 Mulberry tree used for making of sports goods. 

💥 Dry rot caused due to lack of ventilation. 

💥 Foxiness caused due to over maturity. 

💥 Honey combing caused due to-seasoning. 

💥 Strength of the timber is maximum in the parallel direction. 

💥 10% to 12% is the moisture content of well seasoned timber. 

💥 The age of the tree can be known by annular rings. 

💥 1 st class timber has an average life of more than 10 years. 

💥 1 st class brick should not absorb water more than 20% when immersed in water for about 24 hours, 22% for 2nd class bricks and 25% for 3rd class bricks. 

💥 Crushing strength of 1st class bricks not less than 10.5N/mm^2, 7.5N/mm^2 for 2nd class bricks. 

💥 The main function of alumina in brick earth is to impart plasticity. 

💥 The percentage of alumina in good brick earth is 20 to 30%. 

💥 Excess of alumina in brick earth cause crack and warp on drying. 

💥 Excess of silica cause brittleness. 

💥 20*10*10 cm is the nominal size of the brick. 

💥 19*9*9cm is the standard size of brick. 

💥 50 to 60 % silica in good brick earth. 

💥 Silica makes the brick to retain the shape. 

💥 Kneading –the process of mixing the clay water and other ingredients called. 

💥 60 to 70% turn over in clamp burning where as 80 to 90% turn over in kiln burning. 

💥 Pug mill used for preparation of clay. 

💥 Refractory bricks used in combustion chambers. 

💥 The frog of the brick generally kept on the top face of masonry. 

💥 500 bricks required for one cubic metre of brick masonry. 

💥 Quick lime is calcium oxide. 

💥 Hydraulic lime is obtained from burning of kankar. 

💥 Lime and silica are the main ingredients of the Portland cement. 

💥 C3A is responsible for all undesirable properties of cement. 

💥 Le chatelier apparatus is used for testing the soundness of cement. 

💥 Vicat apparatus used for testing setting time of cement. 

💥 C3A is responsible for intial setting time of cement. 

💥 The intial setting time for ordinary Portland cement not less than 30minute. 

💥 The final setting time should be 10 hour. 

💥 The normal consistency of ordinary Portland cement is 30%. 

💥 Early attainment of strength of cement in rapid hardening of cement is due to finer grinding. 

💥 After storage the strength of the cement is decreases. 

💥 Addition of pozzolana to ordinary Portland cement cause shrinkage. 

💥 Gypsum consists of caso4 and H2O. 

💥 25mm to 50mm is the slump recommended for mass concrete. 

💥 Low heat cement is used in massive concrete structures. 

💥 Calcium chloride is the common admixture to accelerate the intial setting time. 

💥 The basic purpose of retarder in concrete is to increase the intial setting time of concrete. 

💥 Gypsum is most commonly used retarder. 

💥 Carbon influences the maximum properties in steel. 

💥 Wrought iron is the purest form of iron. 

💥 The ultimate tensile strength of steel is 420N/mm^2. 

💥 0.25% of carbon in mild steel. 

💥 Yield stress is used for identifying the quality of structural steel. 

💥 Flemish bond –alternate courses of header and stretcher. 

💥 English bond-alternate header and stretcher. 

💥 The pressure acting on the stones in stone masonry should be perpendicular to the direction of bedding planes. 

💥 Queen closer-the brick is cut into 2 equal parts in length wise. 

💥 English bond is provided in masonry for carrying heavy loads. 

💥 Slenderness ratio-effective length to least radius of gyration, for masonry walls not more than 20. 

💥 The differential settlement in case of sandy soil not more than 25mm. 

💥 In case of foundation on black cotton soil the most suitable method is to replace the poor soil. 

💥 Grillage foundation is the most economical foundation to transmit the heavy load. 

💥 Batter pile is used to resist the horizontal and vertical forces. 

💥 0.9m is the minimum depth of the foundation on clay soil. 

💥 The bearing capacity of a water logged soil can be improved by draining the soil. 

💥 Depth or height of arch-is the perpendicular distance between the intrados and extrados. 

💥 Flat roof is constructed where the rainfall is less and temperature is high. 

💥 Pitched and sloping roofs are suitable for coastal region. 

💥 The maximum number of steps generally restricted is 12. 

💥 Sum of tread and rise must between 400 to 450mm. 

💥 Minimum width of landing should be equal to width of stairs. 

💥 In any good stair case the maximum and minimum pitch is 40* and 25*. 

💥 Doglegged stairs are half turn stairs. 

💥 Horizontal projection at head and sill called horns. 

💥 Revolving door is suitable for entrance in an air conditioned building. 

💥 Attrition test determines the rate of wear of stones. 

💥 Efflorescence-formation of white patches on the brick surface due to presence of alkalies. 

💥 Vanadium steel used in the manufacture of axles and springs. 

💥 Neoprene is suitable for bearing of bridges. 

💥 To produce low heat cement it is necessary to reduce the C3A. 

💥 Timber can be made more fire resistant by sir abel’s process. 

💥 Creosote is derived from wood or coal. 

💥 Excess of sulphur in steel results in red shortness. 

💥 Distemper is used to coat interior surface not exposed to weather. 

💥 Putty is made up of powdered chalk and raw linseed oil. 

💥 The limit of proportionality is applied more in the case of mild steel. 

💥 The compacting factor test determines the workability. 

💥 The split tensile strength is 10% to 15%. 

💥 The approximate ratio between the strength of cement concrete 7 to that of 28 days is 2/3. 

💥 The moisture content of timber is 12%. 

💥 0.85P times amount of water is used ofr intial setting time, 0.72P for soundness cement. 

💥 Lime mortar is generally made with hydraulic lime. 

💥 The texture of sand stone is granular crystalline. 

💥 Seasoning of timber is required to remove sap from timber. 

💥 The ratio of youngs modulus of high tensile steel to that of mild steel is about 1. 

💥 Poly vinyl chloride is thermoplastic material. 

💥 High alumina cement is produced by limestone and bauxite. 

💥 The optimum number of revolutions required for concrete mix is 20. 

💥 Manganese steel used in the manufacture of rails. 

💥 Gauged mortar is obtained by adding sand and lime. 

💥 1300*to 1500* is the temperature range of cement in kiln. 

💥 Before testing setting time of cement one should be test for consistency. 

💥 The super plasticizer in a cement paste is disperse the particles, remove air bubbles and to retard setting. 

💥 Surkhi is added to lime mortar to impart hydraulicity. 

💥 Increase in fineness of cement results in increase in development of strength and leads to higher shrinkage. 

💥 The purpose of frog is to form key joint between brick and mortar. 

💥 Bricks are burnt at a temperature of 900-1200 degree Celsius.