1. Effective stress is the average normal stress carried by the pore water pore air soil particles 2. The shear stress acting on a soil is 100 kPa. The normal stress is 120 kPa. The excess porewater pressure is 60 kPa. The effective stress is 100 kPa 120 kPa 80 kPa 60 kPa

The coefficient of earth pressure at rest for a sand having the Poisson's ratio value of 0.25 is. ?

11.5 Following are the results of a laboratory consolidation test on a sample of undis- turbed clay obtained from the field. Pressure, o' (kg/cm?) Final helght of specimen (cm) 2.540 0.5 2.519 1.0 2.5 2.0 2.428 4.0 2.322 8.0 2.206 16.0 2.09 © Cengage laeming 2014

A CID TXC test was performed on a sample of sand. At the end of consolidation, the back pressure was 140 kPa, and the cell pressure was 340 kPa. At failure, the deviator stress was (ơ1 – 03)f = 200 kPa. a. What was the total pore water pressure, u, at failure? b. Calculate the principle effective stresses, ơi' and os', at failure. c. Calculate the friction angle, d', for this soil.