复杂条件下库岸边坡变形破坏机理及防护

As the deformation failure under complex conditions of a reservoir bank slope may cause casualties and property losses, the research of the failure mechanism and protection is one of the important topics in rock and soil mechanics and geotechnical engineering. Taking reservoir bank slopes of the Three Gorges reservoir region as the study object, which have been obviously damaged in the storage period, combing with the monitoring data in a dozen years and adopting the methods of geological analysis, laboratory and field experiments, large-scale landslide model tests and numerical simulations comprehensively, this project will carry out researches on the geological evolution form, damage degradation mechanical properties of rock and soil, deformation mechanism, geology disaster risk assessment system under great danger and protection technology development and build a geologic model reflecting the dynamic evolution situation according to the typical bank slope by considering complicated conditions including reservoir water, rainstorm, snow melt-water and reservoir earthquakes as main disaster factors. It will also reveal the rock mechanics characteristics and damage evolution under complex conditions, obtain the variation rules of seepage field, stress field and displacement field of typical bank slope, set up the bank slope deformation damage evolution model according to its deformation mechanics. On the basis of dynamic risk assessment system for geological disasters of significant risk in the bank slope, a new economic and practical bank slope retaining structure system will be built, with new engineering and ecological protection techniques integrated into it. The research results have important value in theory and engineering applications.

库岸边坡在复杂条件下的变形破坏将造成人员伤亡和财产损失，库岸边坡变形破坏机理及其防护是岩土力学与岩土工程研究的重要课题。本项目以三峡库区蓄水以来发生明显变形破坏迹象的库岸边坡为研究对象，以库水、暴雨、冰雪融水、水库地震等复杂条件为主要致灾因素，综合采用地质分析、室内试验、现场试验、室内大型滑坡模型试验以及数值模拟等方法，结合库区十余年的监测资料，开展库岸边坡地质环境演化、岩土体损伤劣化力学特性、边坡变形破坏机理、库岸边坡重大危险性地质灾害风险决策及防护体系等问题研究，建立典型库岸段内边坡动态演化地质模型；揭示复杂条件下岸坡岩土体力学特性与损伤演化规律；掌握典型库岸边坡渗流场、应力场、位移场的变化规律；揭示库岸边坡变形破坏机理，建立变形破坏演化模型；基于库岸边坡地质灾害风险决策体系，构建经济实用的库岸边坡新型支挡结构体系，集成工程防护与生态防护新技术。研究成果具有重要的理论与工程应用价值。

库岸边坡变形破坏机理及其防护是岩土力学与岩土工程研究的重要课题，本项目以三峡库区蓄水以来发生明显变形破坏迹象的库岸边坡为研究对象，考虑库水、暴雨、冰雪融水、水库地震等主要致灾因素，综合采用地质分析、室内试验、现场试验、室内大型滑坡模型试验以及数值模拟等方法，结合库区十余年的监测资料，开展库岸边坡在复杂条件下的变形破坏机理及防护技术研究。主要研究成果如下：（1）建立了复杂环境下地质灾害动态时空演化模型，实现了区域解剖—局部解剖—点解剖的有机结合，构建了滑坡动态分类体系；（2）基于大量室内及现场试验，考虑水-岩作用、卸荷损伤、岩土体自重应力及流变等多种因素耦合影响，揭示了复杂条件下岸坡岩土体力学特性与损伤演化规律，获得了典型库岸边坡渗流场、应力场、位移场的变化规律；（3）综合室内大型滑坡模型试验和20余年的监测资料分析，揭示了在库水位变动与冰雪、暴雨联合作用及高频中低强度水库地震作用下库岸边坡变形破坏机理，阐释了复杂条件下库岸边坡水库地震迁移规律及成因机理；（4）基于以上研究成果，对重大危险性地质灾害的风险因子进行识别和优选，运用熵权理论综合确定评价指标的权重，建立了复杂条件下库岸边坡重大危险性地质灾害的风险决策体系；（5）研发防护能力强且经济实用的支挡结构体系，在此基础上，通过对工程防护体系外观结构的优化设计，结合项目组前期在边坡生态绿化与防护方面的研究成果，集成复杂条件下库岸边坡地质灾害工程防护与生态防护相结合的技术体系。研究成果可为复杂条件下库岸边坡变形破坏机理研究及防护技术研发提供科学依据。（6）发表论文106篇，其中SCI/EI收录43篇，授权发明专利42项，出版专著5部。培养硕士研究生33名，博士研究生9名。获得岩石动力学杰出贡献奖1项、湖北省科技进步奖二等奖1项、全国徐芝纶力学优秀教师奖1项、中国航海学会科学技术奖二等奖1项。项目超额完成了预定的研究任务，达到了预期研究目标。