Principle involved in the relationship between submerged unit weight and saturated weight of a soil is based on

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 $$2.0 \times {10^5}\,\,MPa.$$

Maximum strain at the level of compression steel for a rectangular section having effective cover to compression steel as $$d'$$ and neutral axis depth from compression face $${X_u}$$ is

In reinforced concrete, pedestal is defined as compression member, whose effective length does not exceed its dimension by