Question

The change that take place during the process of consolidation of a saturated clay would include

• A. an increase in pore water pressure and an increase in effective pressure
• B. an increase in pore water pressure and a decrease in effective pressure
• C. a decrease in pore water pressure and a decrease in effective pressure
• D. a decrease in pore water pressure and an increase in effective pressure

Answer 1

The correct option is D a decrease in pore water pressure and an increase in effective pressure

When stresses are increased, the excess pore pressure is equal to stress increment at t = 0. Naturally effective stresses decrease by the same stress increment. With the onset of consolidation excess pore pressure starts dissipating and effective stresses increase. Finally at the end of consolidation the stress increment is completely transferred to soil grains and only hydrostatic pore pressure exists. So effective stress is maximum at the end of consolidation.