岩土力学2023，Vol.44Issue(11)：3288-3298,11.DOI:10.16285/j.rsm.2023.0540
考虑地层变异和参数空间变异的浅基础承载力可靠度分析
Bearing capacity of shallow foundations considering geological uncertainty and soil spatial variability
摘要
Abstract
The bearing capacity of shallow foundations is significantly affected by stratum uncertainty,mainly including geological uncertainty and spatial variability of soil properties.The influence of geological uncertainty and soil spatial variability on the bearing capacity of shallow foundations has been separately investigated in previous studies.This study aims to develop a general probabilistic computational framework to reveal the effects of geological uncertainty and spatial variability of soil properties on the bearing capacity of shallow foundations,in which the geological uncertainty is simulated by Markov random field and the soil spatial variability is characterized using log-normal random field in different strata considering variations of the vertical scale of fluctuation.Based on the borehole and soil data collected from Mawan,Shenzhen,shallow foundation bearing capacity analysis is performed according to the proposed computational framework.The subset simulation method is used to accelerate the calculation of the reliability of each scenario,and reduction factors are proposed to reduce the calculation results to different degrees with the aim of simplifying the consideration of spatial variability.Contribution indexes are defined to quantify the effects of the geological uncertainty and spatial variability of soil properties on the bearing capacity results of shallow foundations.The results show that the traditional deterministic bearing capacity calculation will overestimate the bearing capacity of shallow foundations without considering the stratum uncertainty.When the number of boreholes is sparse,the geological uncertainty has a greater influence on the calculation results;when the number of boreholes is sufficient,it is mainly dominated by the spatial variability of soil properties.关键词
浅基础承载力/地层变异/参数空间变异/贡献率指标Key words
bearing capacity of shallow foundation/geological uncertainty/soil spatial variability/contribution indexes分类
建筑与水利引用本文复制引用
姜琪浩,王金铜,侯波,张东明,张晋彰..考虑地层变异和参数空间变异的浅基础承载力可靠度分析[J].岩土力学,2023,44(11):3288-3298,11.基金项目
国家重点基础研究发展计划项目(No.2021YFF0502200) （No.2021YFF0502200）
博士后创新人才支持(No.BX20220234) （No.BX20220234）
中建铁路投资建设集团有限公司资助项目(No.CSCECZJTT-2021-07).This work was supported by the National Key Research and Development Program of China(2021YFF0502200),China National Postdoctoral Program for Innovative Talents(BX20220234)and China Construction Railway Investment and Construction Group Support Project(CSCECZJTT-2021-07). （No.CSCECZJTT-2021-07）
