摘要
基于 Q3 黄土三轴剪切试验确定了应力-应变曲线的初始切线模量,结果表明,初始切线模量随固结围压的增大而减小,随含水量的升高而降低。围压作用下湿陷性黄土的结构损伤性较压硬性更加突出。基于初始切线模量定义的损伤比,能够反映球应力增大和进水增湿作用引起的结构破损变化。根据损伤比建立的应力-应变关系能够考虑加载及浸水耦合作用,为评价湿陷性黄土地基的可能湿陷变形量提供了一条有效途径。
Based on the stress-strain relation of Q3 loess triaxial compression tests with different stress paths, including conventional axial loading, lateral unloading, and constant mean principle stress with different water contents of 2.0%, 8.5%, 15.0%, and 18.0%, the initial tangent modulus were obtained. It was shown that the initial tangent modulus of structural loess decreases with increasing lateral consolidation pressure but decreases with increasing water content, and the damage of loess structure subjected to compression stress is more serious than its hardening due to compressing. Because the initial tangent modulus decreases gradually with the increase of compression stress and water content and reflects the structural damage increase of loess, this parameter can be used to define the damage variables by the composite theory. A structural damage ratio of Q3 loess was proposed by the change of initial tangent modulus between the initial tangent modulus of undamaged loess and completely damaged loess. With the consideration of the coupled action of compression and water content, the constitutive model is proposed in terms of the damage ratio, which is a new approach for evaluating the possible collapse settlement of loess foundations.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2004年第24期4161-4165,共5页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金(10172070)
陕西省自然科学基金(2001c52)资助课题。
关键词
损伤力学
湿陷性黄土
结构
损伤演化
Compression testing
Strain
Stresses
Structure (composition)
