Bearing Capacity of Clay Overlain by Stiff Soil

Abstract

Many soft-clay deposits are overlain by a stiffer layer or crust. The stiff upper layer spreads the applied loads over a wide surface of the soft soil providing an effect similar to surcharge stress. The bearing capacity of the lower soft soil is estimated considering the load spread outside the footing width as a variable surcharge stress. Linear and exponential decreases and a triangular distribution of stresses are analyzed. The improvement in bearing capacity is obtained as a function of the extent and distribution of the surcharge stresses.