Influence of bucket boot on penetration resistance of side-rounded caisson foundation and analysis of soil volume in caisson

FAN Shuntao; LYU Peng; DONG Sheng

doi:10.13984/j.cnki.cn37-1141.2025.06.009

Abstract：During the penetration process of the side-rounded caisson,the soil in the caisson will be high.Too high soil height will make the bucket foundation unable to be installed to the specified depth,thus failing to provide the designed bearing capacity.In practical project,bucket boots are used to im-prove the penetration capacity of the caisson.Therefore,it is necessary to analyze the penetration re-sistance of the caisson under different bucket boots forms and the height of the soil in the caisson to provide a reference for engineering applications.This paper used the Coupled Euler-Lagrangian(CEL)method to simulate the penetration process of the side-rounded caisson,and compared it with the field test data.The result fitted well,which confirming the effectiveness of this method.The influence of the bucket boots form on the end resistance and the height of the soil in the bucket,the influence of the wall thickness and soil weakening parameters on the volume of the soil in the bucket were analyzed.The results showed that the larger the chamfer of the bucket boot,the smaller the end resistance,and the outer chamfer of the bucket base was easier to reduce the height of the soil in the bucket during the penetration process.The greater the wall thickness of the caisson and the sensitivity coefficient of the soil,the greater the soil volume increased ratio of the caisson,the greater the ductility coefficient of the soil,and the smaller the soil volume increased ratio.Finally,the soil volume increased ratio in the bucket was fitted according to the calculation results.The formula of the soil volume provides a refer-ence basis for the engineering installation.