 Hello friends. Let me introduce myself first, I am Mr. Yusuke Kulkarni, assistant professor, Balchen Institute of Technology, Sholapur. Topic of our today's discussion is properties of building materials from selection point of view for construction. Learning outcomes of today's session are at the end of this lecture students will be able to enlist building materials, describe use and physical properties of different building materials. Definition and types. Materials which are used in building constructions or civilian constructions are known as building materials. There are number of building materials such as cement, sand, aggregates, water, all of these make concrete, so concrete is one more material which is formed from these. In mortar, bricks, stones, tiles, steel, aluminum, timber and so more. Let us discuss few of these today in detail. Here we can see one image in which different building materials are shown. Here you can see steel bars which are used as reinforcement in concrete. These are coarse aggregates which is ingredient of concrete, this is sand which is also ingredient of concrete, this is cement. Cement comes in bags of 50 kg, these are the bags of cement. These are bricks, so these are the few of the building materials. Now let us first see cement, one important material which forms important ingredient of concrete. The cement is a binding material which binds sand and aggregates together in concrete, in presence of water. And what are the ingredients in cement or how the cement is manufactured? It is manufactured in a powdered form and its ingredients are silica, lime, alumina, gypsum, clays and cell in definite proportions. There are many types of cement, few of them are ordinary Portland cement, Portland Pozolana, fly cement, white colored cement and so on. Now let us see what are the physical properties of cement as per IS Indian Standard 269 2013. These are the physical properties of cement, consistency in the range of 30 to 35 percent. Consistency of cement means its ability to get mixed with water and 30 to 35 percent water is sufficient to make a good paste of cement. Then fineness when sieved through 90 micron sieve, the overdue which is there should not be more than 10 percent, it should be less than 10 percent. Then initial setting time of cement, it should not be less than 30 minutes, remember. Otherwise cement will quickly set, it will not give us time to place it on site. Then final setting time, it should not be more than 600 minutes, it should be less than 600 minutes that means 10 hours. Soundness when tested on leach atelier molds, the expansion of these molds should be less than 10 mm. This strength after 28 days of curing should be minimum 43 Newton per mm square for 43 grade of cement. So, for 33 grade of cement, this will be 33 Newton per mm square and for 53 grade of cement, this will be 53 Newton per mm square. So, cement comes in three grades namely 33, 43 and 53 Newton per mm square capacities. Now let us discuss about sand, which is also called as fine aggregate as per IS 383 1970, the specifications are laid down. Now sand which is also known as fine aggregate makes an important ingredient of concrete and also mortar. Sand is available naturally on the banks of rivers, remember. And this sand is sieved through IS 4.75 mm sieve and the particles passing through this sieve are used for making of concrete and mortar. Density of sand is approximately 1800 kg per cubic meter, it may vary and sand should be made dust free before using in concrete, remember. Now coarse aggregate, these are coarser particles, so it is called coarse aggregate as per IS 383 again, the specifications are there and building stones are crushed and their particles are formed and sizes of these particles are 40 mm, 20 mm, 10 mm, etc. and these are called coarse aggregates. Physical properties of aggregates are density approximately 1600 kg per cubic meter, it may vary from source to source. Generally 20 mm aggregate size is used for making of concrete, concrete coarse aggregate should be angular and water absorption should be less than 1% for making good concrete. Its impact and crushing strength should be good, coarse aggregates for many important ingredient of concrete. Then steel reinforcement, let us see steel bars which are used in concrete for making concrete more stronger in its tensile strength, IS 1786 gives the specifications, high yield strength deform bars called HYSD bars are used, they come in two categories, FE415, 415 is yield strength of steel Newton per mm square and FE500 are these two grades they are used in concrete for making concrete more stronger in tensile strength also, mild steel bars of FE250 grade are also used but as secondary reinforcement in concrete. Circular steel bars are there, they come in the range of 6 mm, 8 mm up to 40 mm. Water makes an important ingredient of concrete remember and potable water should be used for making of concrete, pH value should be 7 and water is required for curing of concrete also, so it is very important ingredient of concrete. Then let us see concrete, concrete IS 456 2000 the specifications are there, what is concrete? Concrete is a composite material obtained from mixing of cement, sand, coarse aggregate and water in definite proportions. There are different grades of concrete and there uses also we will see. Names of concrete are like M10, M15 in which M stands for mix and this number for example 10 stands for characteristic compressive strength of concrete after 28 days of curing. So, M10 means strength after 28 days will be 10 Newton per mm square compressive strength and nominal mix proportions in M10 are 1 is to 3 is to 6, proportions of cement is to sand is to coarse aggregate and these are the concretes used for works of lower importance. M15 is next concrete grade whose proportion nominal mix proportions are 1 is to 2 is to 4, compressive strength 15 Newton per mm square and this concrete is also used for works of lower importance below foundation for bed in compound walls etc. The next M20 grade, this is important grade of concrete used everywhere for all the building constructions structural components like slabs, beams and columns, foundations. Nominal mix of proportions of this concrete are 1 is to 1.5 is to 3, compressive strength 20 Newton per mm square. M25 is the next, its nominal mix proportion is 1 is to 1 is to 2, compressive strength is 25 Newton per mm square and this concrete is used then for water tanks, water tanks, hydraulic structures where high precision is required and concrete of higher grade is useful there. M30 and above all these mixes are designed, mixed design is done and compressive strength for M30 will be 30 Newton per mm square and these concretes are used for pre stress concrete, dam constructions, high rise structures etc. Concrete up to grade M60 may be there, M60 or nowadays M100 they are getting bricks. Standard dimensions of bricks are 190 mm by 90 mm by 90 mm. Here you can see image of a brick, image of bricks. These bricks are used for construction of walls remember, they are having prog here provided prog so that there is good bond between two layers of bricks. Specifications of first class bricks as per IS 1077, all bricks should be of first class of standard specifications, brick should be made of good earth, very soil well burnt, they should not absorb water more than 20%. Some crushing strength of bricks should be 35 Newton per mm square, when fallen from a height of 1 meter on ground it should not get broken remember, this is important. And bricks should be of deep cherry red copper color, regular in shape, edges of the brick should be sharp, when struck they should emit clear ringing sound, there should not be any cracks, chips and flaws in bricks. Building stones as per IS 3 3 1 6, their appearance should be good when these are used for face work they should have uniform color, pleasing color and they must be free from cracks cavities flaws etc. Strength of building stone crushing strength should be from 60 to 200 Newton per mm square, hardness toughness and resistance operation should be good, durability should be good, porosity should be less porous, not more than 1% water should be absorbed, resistance to fire should be there, specific gravity from 2.4 to 2.8, little pause we will take here friends, these are two questions solve them, what should be minimum compressive strength of cement 43 grade cement and first class brick solve them, so answers are OPC 43 Newton per mm square, first class bricks 35 Newton per mm square. Here we can see construction work in progress, these are the references for today's session, thank you.