The factor of safety for the embankment constructing on soft clay is minimum at the end of construction. After that consolidation takes place, thereby increasing the shear strength of foundation soils. Reinforcement is normally introduced to maintain the stability owing to the following reasons:
(i) The reinforcement at the clay surface, which is capable of carrying tensile forces, generates shear stresses to resist the lateral deformation of clay and improves its bearing capacity.
(ii) The reinforcement could also hold in equilibrium the lateral trust developed by the fill above so that it reduces the stresses which tends to cause failure of clay foundation.
(iii) The reinforcement has a tendency to drive the failure mechanism deeper in the soft clay, which should possess higher shear strength because its strength generally increases with depth.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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