残积土的短时冻融累积损伤效应与边坡浅层多重失稳机制

项目名称： 残积土的短时冻融累积损伤效应与边坡浅层多重失稳机制

项目编号： No.41302215

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 阙云

作者单位： 福州大学

项目金额： 23万元

中文摘要： 短时冻土具有冻融次数频繁、冰雪融化后土质含水率高等特点。现场调查表明，短时冻土区残积土边坡浅层冻融垮塌频发，但相关基础理论研究一直未得到重视。项目以短时冻融循环与冰雪融化入渗为主线，重点研究短时冻融循环与冰雪融化入渗诱发残积土边坡浅层多重失稳机制。具体为：基于短时冻土区气候环境监测资料与室内试验，揭示短时冻融循环下残积土与冻融界面强度累积损伤特性，提出随含水率和冻融次数变化的残积土与冻融界面强度参数累积损伤模型；构建考虑融雪入渗的土壤大孔隙两域渗流模型以及考虑相变的短时冻土水热耦合模型，揭示冰雪融化入渗下残积土边坡的水热耦合效应，并与室内土柱模型试验对比验证；基于考虑残积冻土损伤的水-热-力三场耦合模型，分析短时冻融循环与冰雪融化入渗条件下残积土边坡温度场、水分场、应力场与变形场多场相互作用机制以及多重垮塌模式，并开展现场试验验证研究。成果可为短时冻土区残积土质边坡的灾害防治提供理论依据。

中文关键词： 短时冻土；冻融损伤；大孔隙流；多场耦合；多重失稳

英文摘要： Short-term frozen soil has the characteristics of great frequency of short- term freeze-thaw and high moisture content under the condition of snow infiltration. The results of the field investigation show that shallow collapse disease of residual soil slope occurred frequently. Unfortunately, the related basic theory has not been given enough attention. Taking short-term freeze-thaw cycles and snow infiltration as the main line，this project mainly studies on shallow multiple instability mechanism of residual soil slope induced by short-term freeze-thaw cycles and snow infiltration. The main content of the project is as follow：Firstly, strength damage model of residual soil and the freeze-thaw surface considering the change of moisture content and freeze-thaw cycles are proposed by laboratory test based on the monitoring data of climate environmental in short-term frozen soil area. Secondly, on the basis of model of soil macropore flow under the condition of snow infiltration and moisture-temperature coupling model considering the phase transition in short-term frozen soilt, the effect of moisture-heat coupling of residual soil slope under the condition of snow infiltration is revealed.Thirdly, the interaction mechanism of temperature field, moisture field, stress field and deformation field and multiple collapse

英文关键词： short-term frozen soil；freezing-thawing damage；macropore flow；multi-field coupling；mutipile slide