Proceedings of DFI-India 2018: 8th Conference on Deep Foundation Technologies for Infrastructure Development in India, (DFI)
Extent of Failure Zone in Soil at the Cutting Edge of Open Caisson: FE Evaluation and Regression Analysis
Jitesh T. Chavda, Research Scholar and G. R. Dodagoudar, Professor
Open caissons are deep foundations sunk into the ground by removal of soil within the caisson shaft. A cutting edge with a tapered inner face is used at the bottom of the caisson to allow the bearing failure of the soil which is in contact with the cutting edge. The soil is removed within the shaft of the caisson during sinking which results in bearing failure of the soil due to self-weight of the caisson. The formation of influence zone in the soil at the cutting edge is termed as failure zone. In this study, the finite element (FE) analysis is carried out to evaluate the extent of failure zone in the c-? soil at the cutting edge of the open caisson. The cutting edge is penetrated into the soil and the extent of the failure zone is evaluated. The effect of variation of tapered angles of the cutting edge, the radii ratio of the open caisson, unit weight, friction angle and cohesion of the soil, and magnitude of the surcharge on the extent of the failure zone is investigated. From the FE results, the multivariate linear and nonlinear regression analyses are performed and easy to use predictive equations are developed to estimate the extent of failure zone in the soil beneath the cutting edge. These equations help in quick estimation of the extent of failure zone based on the configuration of the open caisson adopted at the construction site.
|article #3147; publication #1050 (India2018)|