摘要
针对大、小变形法地基沉降量结果的差异问题,从大变形应力和应变度量、本构关系以及本构参数等概念的角度进行探讨。在连续介质力学有关原理基础上,先后研究了基于Green应变、Almansi应变和自然应变的地基大变形沉降量计算式。基于欧拉应力——Almansi应变对、欧拉应力——自然应变对的大变形法压缩本构关系整理方法,以及大、小变形法切线体积压缩系数之间的转换方法等。理论分析和算例分析结果表明,遵循该转换关系的条件下,同一问题所得的大、小变形法最终沉降量结果是相同的,忽略该转换关系将导致大变形法沉降量计算结果偏大或偏小于小变形法的结果,这也为合理确定大变形法本构参数提供新的参考。
Aimed at the controversy on the results of ground settlements predicted both by large-strain and small-strain methods, the significant concepts of finite-strain stress and strain measures, constitutive relations and related parameters etc., are investigated. Based on fundamentals of continuum mechanics, the large-strain settlement formula in respect to Green strain, Almansi strain, and natural strain are presented. The large-strain constitutive relationship of soil compression is proposed with respect to Euler stress - Almansi strain pair and Euler stress - natural strain pair. A transform method between the tangent volume compressibility coefficients using large-strain and small-strain schemes is put forward. The theoretical analysis and the corresponding case study show that the computational settlements by large-strain and small-strain methods should be identical in the case of strictly following the presented transform method; otherwise the value of large-strain settlement might be over or under that of small-strain method. The transform method can also provide new reference for determining reasonably the large-strain constitutive parameters.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2009年第7期1920-1926,共7页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No50708077)
北京交通大学科技基金资助项目(No2008RC025)
中国博士后科学基金项目(No20060400177)
关键词
地基沉降
大变形
本构关系:有限应变
切线体积压缩系数
foundation settlement
large deformation
constitutive relation
finite strain
tangent volume compressibility
