Civil Engineering UPSC PYQ 2019

A 6 m high retaining wall supports a dry cohesionless backfill with horizontal surface. The backfill has unit weight gamma = 17.5 kN/m^3 and angle of internal friction phi = 34 deg. A uniform surcharge load of 20 kN/m^2 acts on the ground surface. Find the total active lateral thrust on the wall per meter length and its location above the base. If the water table rises to a height of 2.5 m above the base with gamma_sat = 19.5 kN/m^3, compute the new total thrust and its point of application.

Design a simply supported one-way reinforced concrete slab for an office floor with clear span of 3.5 m. The slab is supported on 230 mm thick masonry walls. Live load = 4.0 kN/m^2, floor finish = 1.0 kN/m^2. Use M 20 grade concrete and Fe 415 grade steel. Apply limit state design method and check for deflection control.