地基承载力深度和宽度修正系数分析  

Analysis of depth and width correction factors for bearing capacity of foundation soil

作　　者：介玉新[1] 傅志斌[2] 王杨强 殷常运 JIE Yuxin;FU Zhibin;WANG Yangqiang;YIN Changyun(State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China;China Institute of Geotechnical Investigation and Surveying Ltd,Beijing 100007,China)

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [2]建设综合勘察研究设计院有限公司,北京100007

出　　处：《清华大学学报（自然科学版）》2023年第11期1897-1908,共12页Journal of Tsinghua University(Science and Technology)

基　　金：国家自然科学基金项目(52090081,52108372);青年北京学者基金(2017A30);广西岩土力学与工程重点实验室开放基金项目(15-KF-01)。

摘　　要：在大面积人工填土的地基承载力计算中,中国现行《建筑地基基础设计规范》(以下简称《规范》)不考虑对基础宽度的修正,得到的地基承载力偏小,对工程安全有利,但在一些情况下却不够经济。该文对这一问题进行探讨,分析了地基承载力的定义、度量方法、相关理论原理和容许承载力的取值方法,探讨并推测了此前在人工填土、软弱下卧层等地基承载力修正系数选择上的可能依据。考虑到当前施工和监测技术相较于早期规范制定时已有很大进步,认为在满足一定条件下可考虑修正地基承载力宽度,并且可适当提高现有的深度和宽度修正系数取值。[Objective]The determination of bearing capacity of foundation soil is one of the classical research fields of soil mechanics.For large area artificial fill projects,the current specifications of China do not consider the correction factor of foundation width in the calculation of bearing capacity.This paper discusses this problem,and investigates the definition and measurement methods of the foundation bearing capacity,related theoretical principles,and the method of determining allowable bearing capacity.We also discuss and speculate the possible basis for the selection of correction factors of the bearing capacity of foundation soil made of artificial fill and soft underlying stratum.It may provides theoretical guidance for width and depth correction of bearing capacity of foundation soil in large area artificial fill under current technical conditions.[Methods]In this paper,two main approaches for calculating bearing capacity of foundation soil are studied.One is to determine the bearing capacity of the foundation soil according to the extension range of the plastic zone;the other is to use the ultimate load as the ultimate bearing capacity,and then divide it by the safety factor to obtain the bearing capacity.The width and depth correction of bearing capacity is also based on these theories.We reviews the sources of the calculation method of bearing capacity together with the width and depth correction factors in the current specifications of China.On the basis of deriving the calculation formula and analyzing the principle of bearing capacity of foundation soil,two cases are investigated in this paper:one is a homogeneous foundation soil,and the other is that the shear strength of the soil outside the foundation boundaries is lower than the foundation soil.The possible essence for the correction factors of the bearing capacity is then discussed in order to guide the determination of the width and depth correction factors for large area artificial fill.[Results]For large area artificial fill projects,the cor

关 键 词：地基 极限承载力 容许承载力 深度修正系数 宽度修正系数 

分 类 号：TU43[建筑科学—岩土工程]