平面应变条件下上海软粘土初始损伤试验研究  

Study of Initial Damage of Shanghai Soft Clay under the Condition of Plane Strain

作　　者：陈柏全[1] 袁聚云[1] 董建国[1] 

机构地区：[1]同济大学地下建筑工程系

出　　处：《勘察科学技术》2008年第5期11-14,共4页Site Investigation Science and Technology

摘　　要：材料力学中假设材料是各向同性的均匀介质,但在电子显微镜或光学显微镜下看到材料远非均匀,因而也不可能是各向同性的,岩土材料更是如此。岩土材料内部有许多孔隙和微裂缝,在一定外部荷载作用下,微裂缝会不断地扩展,使材料的强度和刚度等力学性能下降,这些导致材料和结构力学性能劣化的微观结构变化称为损伤。由于损伤的出现,使材料的力学性能下降,因此,如何能够准确的确定土的初始损伤门槛值,对工程实践意义重大。该文就上海软粘土初始损伤门槛值确定方法进行了研究,并提出了损伤线的概念和确定方法。As we know, materials are assumed as isotropic and homogeneous medium in the mechanics of materials, but they are far from homogeneous materials in electron microscope or optical microscope observation, therefore it is impossible to regard as isotropic, especially for geotechnical materials. There are many micropores and cracks in the inner of geotechnical materials. Under a certain external loads, micro-cracks will continue to expand, the strength and stiffness of the mechanical properties will decrease. These lead to deterioration of the mechanical properties of micro-structural changes so called damage. Because of damage appearing, the mechanical properties of materials decrease. Therefore, how to accurately determine the initial damage threshold of soil has important significance for engineering practice. In this paper, we study the methods for determining the initial damage threshold of Shanghai soft clay, and put forward the concept of damage line and methods of determination.

关 键 词：初始损伤 损伤线 门槛值 平面应变 有效应力 灰色粘土 

分 类 号：TU442[建筑科学—岩土工程]