Question

QUESTION (1):

A clay till has a cohesion of 10 kPa and a friction angle of 30 degrees. The vertical stress in the unit is 90 kPa and horizontal stress is 50 kPa. The porewater pressure in the clay till is 40 kPa. Using effective stress, sketch the Mohr circle and failure envelope for the clay till. Is failure expected?

(Question Continue from question 1)

Assume that the clay till has been subjected to displacement due to shearing in the past, and the cohesion in the unit is zero. Sketch the new failure envelope and re-evaulate for failure.

Is failure expected?

Question (2):

There is a 2 m change in head over 100 m distance, the hydraulic conductivity is 10^-6 m/s, and the porosity is 0.30. Calculate the specific discharge in m/year. (Numeric answer only, report to 2 significant figures)

Answer 1