大厚度自重湿陷性黄土力学特性及湿陷变形规律

项目名称： 大厚度自重湿陷性黄土力学特性及湿陷变形规律

项目编号： No.51509257

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 水利工程

项目作者： 姚志华

作者单位： 中国人民解放军空军工程大学

项目金额： 20万元

中文摘要： 黄土地区工程建设遇到的大厚度自重湿陷性黄土越来越多，但相应的工程经验和理论认识不够丰富，针对大厚度自重湿陷性黄土研究的欠缺和空白，以兰州和平镇大厚度自重湿陷性黄土为研究对象，通过室内非饱和土试验、理论建模和数值模拟等手段，对其力学特性和湿陷变形规律进行研究，主要内容包括：进行一系列的非饱和原状Q3黄土及其重塑土的力学试验，研究其变形、强度、屈服和持水特性；以Barcelona非饱和土弹塑性修正模型为基础，引入非饱和原状Q3黄土加载和湿陷过程中的结构演化方程，提出完善的非饱和原状Q3黄土结构性本构模型；以连续介质力学为基础，建立非饱和原状Q3黄土流固耦合模型，并设计相应的有限元程序，对黄土场地的现场浸水试验进行多场耦合分析。本项目成果可以为大厚度自重湿陷性黄土地区的工程建设提供理论支持和科学依据。

中文关键词： 大厚度自重湿陷性黄土；力学特性；湿陷变形；结构性；渗流固结

英文摘要： There are more and more self weight collapsible loess with heavy section in the engineering construction of collapsible loess area, but the theory understanding and relevant engineering experience are poor. Aiming at research deficiency of the self weight collapsible loess with heavy section, taking the self weight collapsible loess with heavy section in Heping Town, Lanzhou city as the study object, its collapsible deformation and mechanical properties are researched by the methods of the indoor unsaturated soil tests, theoretical modeling and numerical simulation. The main contents includes, a series of mechanical tests of unsaturated undisturbed Q3 loess and its remolded soil are carried out to reveal the deformation, strength, yield and water holding characteristics. On basis of Barcelona unsaturated soil elastoplastic modified model, structural constitutive model of unsaturated undisturbed Q3 loess is established by using of damage evolution equation during loading and collapsing process. Based on the continuum mechanics, a seepage consolidation coupling model of undisturbed Q3 loess is presented. The corresponding seepage consolidation finite element program is compiled to simulate the in-situ soaking test in collapse loess ground with heavy section. The project results would provide theoretical support and scientific basis for engineering construction in self weight collapse loess regions with heavy section.

英文关键词： self-weight collapse loess with heavy section;mechanics properties;collapsible deformation;structure;seepage- consolidation