Influence of Shape of Cross Section on the Load–Settlement Behaviour of Strip Footings

Abstract

The bearing capacity of footings has been extensively studied, both theoretically and experimentally over the past decades. In all the type of footings except shell foundations, the shape of the cross section adopted is rectangular and the base has been considered as a plane surface. The pattern of soil movement beneath the footing during loading is a significant factor contributing to the load–settlement behaviour. By altering the shape of the cross section of the footing, it would be possible to provide better confinement of underlying soil thereby improving the load–settlement behaviour. This paper investigates the influence of the shape of the cross section of the footing on its behaviour. The different shapes of the cross section of footing adopted for the study are sloped cross section, curved cross section and rectangular cross section with vertical flanges. A series of non-linear finite element analyses are carried out with the FE software PLAXIS 2D and the results are validated by carrying out laboratory scale load tests and comparing the results. It is observed from the results that the load–settlement behaviour of the footings can be significantly improved by altering the shape of the cross section. The improvement is significant when the shape of the cross section is Curved or Rectangular with flanges. The optimum length of flanges is observed to be 20% of the width of the footing.