In an oedometer apparatus a specimen of fully saturated clay has been consolidated under a vertical pressure of 100 kPa and is at equilibrium state. Immediately on increasing the vertical pressure to 150 kPa , the effective stress $\sigma^{\prime}$ and excess pore water pressure $\Delta u$ will be
A soil sample is underlying a water column of height h1, as shown in the figure. The vertical effective stresses at point A, B and C are $$\sigma {'_A}$$, $$\sigma {'_B}$$ and $$\sigma {'_C}$$ respectively. Let $$\gamma$$sat and $$\gamma$$' be the saturated and submerged unit weights of the soil sample, respectively and $$\gamma$$w be the unit weight of water. Which one of the following expressions correctly represents the sum ($$\sigma {'_A}$$ + $$\sigma {'_B}$$ + $$\sigma {'_C}$$) ?