7. The initial effective stresses on a saturated soil element at a certain depth in a soil mass are o', = 40 kPa, oʻ2 = 20 kPa, and o'z = 20 kPa. The groundwater level is well below the soil element....

Extracted text: 7. The initial effective stresses on a saturated soil element at a certain depth in a soil mass are o', = 40 kPa, oʻ2 = 20 kPa, and o'z = 20 kPa. The groundwater level is well below the soil element. The changes in stresses on the soil element are shown in Fig. 5. 100 kPa 20 КPа 50 kPa O kPa О КРа 20 kPa Fig.5 a) Calculate the change in principal stresses; b) Plot the total stress path in (p, q) space.