A beam with a rectangular cross section of size $$250$$ $$mm$$ wide and $$350$$ $$mm$$ deep is prestressed by a force of $$400$$ $$kN$$ using $$8$$ numbers $$7$$ $$mm$$ $$\phi $$ steel cables located at an eccentricity of $$75$$ $$mm.$$ Determine the loss of prestress due to creep of concrete. Grade of concrete is $$M40;$$ Coefficient of creep is $$2;$$ stress at transfer is $$80\% $$, Modulus of elasticity of steel $$\left( {{E_s}} \right)$$ is $$2.0 \times {10^5}\,\,MPa.$$

In section, shear centre is a point through which, if the resultant load passes, the section will not be subjected to any

Two steel plates each of width $$150$$ $$mm$$ and thickness $$10$$ $$mm$$ are connected with three $$20$$ $$mm$$ diameter rivets is placed in zig-zag pattern. The pitch of the rivet is $$75$$ $$mm$$ and gauge is $$60$$ $$mm.$$ If the allowable tensile stress is $$150$$ $$MPa,$$ the maximum tensile force that the joint can withstand is

The problem of lateral buckling can arise only in those steel beams which have