PERMISSIBLE STRESSES (CLAUSE B-2, IS456:2000)

PERMISSIBLE STRESSES (CLAUSE B-2, IS456:2000),Permissible Stresses in Concrete ( IS 456),Permissible Stress in Steel Reinforcement ( IS 456) PERMISSIBLE STRESSES (CLAUSE B-2, IS456:2000) The working stress method is based upon the concept of permissible stresses. Permissible stresses are obtained by dividing the ultimate strength of concrete or yield strength of steel (0.2% proof stress) by appropriate factors of safety. The factors of safety used in working stress method are: (i)        For concrete (a) in bending compression - 3.0 (b) in direct compression - 4.0 (ii)       For steel - 1.78 There are greater chances of variation of strength of concrete due to improper compaction, inadequate curing and variation in the properties of concrete. The chances of variation in the properties of steel are less as it is fabricated in factories where good workmanship and better quality control is possible. So, lesser value of factor of safety is used for steel as…

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Types of R.C.C. beam, Fundamental assumptions of elastic theory of bending

Learn: Types of R.C.C. beam,Singly,doubly and T, Flanged Reinforced Beams,fundamental assumptions of elastic theory, Assumptions in the theory of simple bending of R.C.C. beams(Working stress method) Plain Cement Concrete has low tensile strength. A beam made up of plain cement concrete will have low load carrying capacity and will fail by cracking in the tension zone. It is therefore reinforced by placing steel bars in the tensile zone. These bars will take up the tensile stresses and thus increase the load carrying capacity or strength of the beam. The steel placed in the tensile zone, is called as longitudinal steel or main steel.  TYPES OF R.C.C. BEAM            Types of  R.C.C. beam are of following :             (i)        Singly Reinforced Beams : This is the one of Types of  R.C.C. beam in which steel reinforcement is placed in the tensile zone only are called as singly reinforced beams.             (ii)      …

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