Cantilever retaining wall is constructed to retain the earth in order to create a change of elevation. The stability aspect of a retaining wall is important to prevent any failure of the structure. Referring to Figure 2, check the stability of the cantilever retaining wall against: (1) Sliding (ii) Rotation (ii) Bearing failure (iv) Stability 5 Marks 4 Marks 3 Marks 2 Marks 0.5 m 3.0 m 0.6 m 1.0 m 0.5 m t Concrete Figure 2 In order to calculate item (ai), (ai), and (ai); below are the details of the cantilever retaining wall: (a) Height of retain excavation = 5.0 m high (b) Unit weight of concrete = 24 kN/m3 (c) Allowable bearing capacity of the soil beneath the wall (qalw) = 150 kN/m? (d) Interface friction angle between the base of wall and soil ('b) = 18 (e) Unit weight of backfill soil (Y') = 18 kN/m3 %3!