基于广义位势理论的岩土塑性应变增量方向非唯一性问题  

Problem on non-uniqueness of direction of plastic strain increment of geomaterials based on generalized potential theory

作　　者：温勇[1,2,3] 杨光华[1,2,3] 傅旭东[1] 钟志辉[1] 姚捷[4] 

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072 [2]广东省水利水电科学研究院,广东广州510610 [3]广东省岩土工程技术研究中心,广东广州510610 [4]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《中南大学学报（自然科学版）》2015年第4期1428-1435,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51378131;51378403;51174093);中央高校基本科研业务费专项资金资助项目(2012210020203)~~

摘　　要：基于广义位势理论提出的考虑拟弹性的弹塑性模型(拟弹性弹塑性模型)把总的塑性应变分解为满足弹性分解准则的拟弹性部分和符合传统塑性理论假设的纯塑性部分,这样分解后建立的模型更为合理和简便,同时又可以解决岩土塑性应变增量方向非唯一性的问题。研究结果表明:基于广义位势理论的拟弹性弹塑性模型的模拟效果较好,传统的弹塑性模型只能反映塑性应变增量方向的唯一性,而拟弹性弹塑性模型则能够同时反映塑性应变增量方向的唯一性(高应力水平时)和非唯一性(低应力水平时),结果更符合实际,从而为解决塑性应变增量方向非唯一性问题提供了一种有效的方法。An elastic-plastic model considering quasi-elastic deformation（quasi-elastic-plastic model） was proposed based on the generalized potential theory, of which the traditional plastic strain increment was decomposed into quasi-elastic part and pure-plastic part. The quasi-elastic part obeys elastic rule and the pure-plastic part obeys the traditional plasticity theory. The proposed model is more reasonable and convenient, and it can solve the problem of non-uniqueness of the direction of plastic strain increment of geomaterials. The results of test validation show that the simulation effect of the quasi-elastic-plastic model based on the generalized potential theory is good. The traditional elasto-plastic model can only reflect the uniqueness of the direction of plastic strain increment, while the quasi-elastic-plastic model can reflect the uniqueness（in high stress level） and the non-uniqueness（in low stress level） of the direction of plastic strain increment simultaneously. It proves that the quasi-elastic-plastic model based on the generalized potential theory conforms to reality better than the traditional elasto-plastic model and it provides an effective method for the study on the problem of non-uniqueness of the direction of plastic strain increment.

关 键 词：广义位势理论 塑性应变增量方向 非唯一性 拟弹性弹塑性模型 

分 类 号：TU452[建筑科学—岩土工程]