Extracted text: 5-4 For the given soil profile and the piezometric surfaces measured at the top of the two sand and gravel layers, determine the pore pressure and effective stress at points A, B, C, D, and E. Piezometers 2 m Ground surface 2 m Sand y = 18 kN/m3 Water table y_ 11m Y = 20 kN/m3 A 4 m Clay Y = 18 kN/m3 加。B 1Im 5 m Sand and gravel y = 22 kN/m3 2 m •D 5 m Clay Y = 19 kN/m3 Sand and gravel y = 23 kN/m3 %3D Cpyright by