适用于海洋土的弹塑性本构模型  

Elasto-Plastic Constitutive Model Suitable for Marine Soil

作　　者：陈小奔 戚承志 郭云鹏 王玉琪 Chen Xiaoben;Qi Chengzhi;Guo Yunpeng;Wang Yuqi(School of Civil and Traffic Engineering,Beijing Advanced Innovation Center for Future Urban Design Beijing University of Civil Engineering and Architecture,Beijing 100044)

机构地区：[1]北京建筑大学土木与交通工程学院北京未来城市设计高精尖创新中心,北京100044

出　　处：《北京建筑大学学报》2018年第3期1-5,17,共6页Journal of Beijing University of Civil Engineering and Architecture

基　　金：国家自然科学基金项目(51478027;51774018);国家重点基础研究发展计划(973计划)(2015CB57805);长江学者和创新团队发展计划(IRT_17R06)

摘　　要：高围压和高孔隙水压会对海洋土的力学性质产生影响,一方面会在土颗粒之间形成黏结应力,另一方面会使土的剪胀行为逐渐过渡为剪缩行为.基于修正剑桥模型理论,引入修正参数α,改进修正剑桥模型剪胀方程,使它能够反映砂土的剪胀特性和剪切强度随有效围压增大而增大的特点.同时修改原修正剑桥模型的屈服面,考虑黏结应力pb的影响,从而建立能够反映海洋土力学性质的弹塑性本构模型.最后将改进后的模型理论值与已发布文献中试验值对比,发现二者具有较好的一致性,表明了该模型的合理性.The high confining pressure and high pore water pressure affect the mechanical properties of the marine soil. On the one hand, it will form the bond stress between the soil particles. On the other hand, the dilatancy behavior of the soil will be transferred to the shrinkage behavior gradually. Based on the modified Cambridge model, the modified parameters a are introduced to improve the dilatancy equation of the modified Cambridge model, so that it can reflect the dilatancy behavior and shear strength of the sand increased with the effective confining pressure. At the same time, the yield surface of the model is modified and the influence of bond stress Pb is considered to establish an elastoplastic constitutive model which can reflect the mechanical properties of marine soil. Finally, compared the calculated values of the improved model with the experimental values published in the literature, it is found that both of them have good consistency, which indicate the rationality of the model.

关 键 词：高围压 修正剑桥模型 剪胀行为 

分 类 号：TU432[建筑科学—岩土工程]