(Solved): a) Why is the determination of lateral earth pressure important in Geotechnical engineering? (4 ma ...

a) Why is the determination of lateral earth pressure important in Geotechnical engineering? (4 marks) b) Using Mohr-Coulomb theory, explain the development of passive earth pressure. (6 marks) c) In the retaining wall shown in Fig. 2, calculate the Rankine active force, \( P_{\mathrm{a}} \), per unit length of the wall and the location of the resultant after the occurrence of the tensile crack. (10 marks) \[ \begin{array}{ll} H=7.5 \mathrm{~m} & \gamma=18 \mathrm{kN} / \mathrm{m}^{2} \\ \phi=20^{\circ} & c=13.5 \mathrm{kN} / \mathrm{m}^{2} \quad \alpha=10^{\circ} \end{array} \]