西南高寒地区冰积土坝料流固耦合宏细观渗流变形本构关系研究

Glacial soil is adopted to build earth-rock dams in southwest China alpine region because traditional materials are lack. Scientifically understanding to the macroscopic and microscopic fluid-solid coupling seepage deformation mechanisms of glacial soil under hydro-pressure has been a key issue which needs to be urgently solved in the reliability evaluation of earth-rock dams. This research project was carried out supported by the Gushui and Rumei earth-rock dams which are located in the southwest China alpine region. Based on the stereology, soil mechanics, nonlinear continuum mechanics, mesomechanics, fluid-structure interaction theory and modern material testing technology, the micro-structure model of glacial soil will be established in this project. Then, fluid-solid coupled isotropic nonlinear consolidation model of glacial soil under hydro- pressure will be built. Constitutive relationship of continuum porous media seepage deformation for glacial soil will be also established. The constitutive relationship of macroscopic and microscopic fluid-solid coupling seepage deformation of glacial soil will be built via the micro level porosity variation in glacial soil under stress. The study aims to analyze the change rules of micro-structure in glacial soil under stress, to illuminate the macroscopic and microscopic seepage deformation coupling mechanism of glacial soil which is bear by complex stress load, to reveal the macroscopic and microscopic coupling mechanism of seepage deformation in glacial soil earth-rock dams. The study will provide scientific basis and theoretical guidance for the stability evaluation of earth-rock dams which are made up of glacial soil coupling by seepage and deformation.

由于缺乏传统筑坝材料,西南高寒地区土石坝工程广泛采用冰积土坝料。科学认识水压作用下冰积土坝料流固耦合宏细观渗流变形作用机理,是评价水压作用下冰积土坝料土石坝工程可靠性所亟待解决的关键问题之一。本项目选择西南高寒地区古水、如美等水电站土石坝工程为研究对象，运用体视学、土力学、非线性连续介质力学、细观力学、流固耦合理论等理论与现代材料测试技术，构建冰积土细观组构模型、宏观层面水压作用下冰积土各项同性流固耦合非线性固结模型、细观层面冰积土多孔连续介质渗流变形本构关系，通过宏观受力条件下冰积土内细观孔隙率的变化量，建立流固耦合作用下冰积土坝料统一的宏细观渗流变形本构关系，分析宏观受力条件下冰积土材料细观组构的变化规律、阐明复杂应力路径条件下冰积土的宏细观渗透变形机理及耦合效应、揭示冰积土坝料高土石坝宏细观渗流变形耦合作用机理。研究成果可为评价冰积土坝料土石坝渗流变形稳定提供科学依据和理论指导。

国家自然科学基金项目“西南高寒地区冰积土坝料流固耦合宏细观渗流变形本构关系研究”（No.11862024）2018年8月立项，研究时段为2019年1月至2022年12月。项目主要针对西南高寒地区土石坝工程广泛应用冰积土坝料、评价水压作用下冰积土坝料土石坝工程可靠性需重点研究的实际，研究水压作用下冰积土坝料高土石坝宏细观渗流变形耦合作用机理。截止目前，项目组按既定研究计划完成了研究任务，达到预期目标。本项目完成了冰积土物理力学性能、细观组构研究，宏观受力条件下冰积土坝料细观组构变化规律研究，复杂应力路径条件下冰积土宏细观渗流变形耦合作用机理研究，复杂应力路径条件下冰积土流固耦合宏细观渗流变形本构关系研究等研究内容。项目研究共发表学术论文24篇，其中SCI收录11篇（JCR Q1区3篇、JCR Q2区5篇），SCI收录论文累计影响因子49.492，被引用63次；获发明专利授权3项、实用新型专利授权3项、省级工法1项；参编行业标准2项；项目研究在国内学术会议开展大会特邀（主题）报告2次；获省部级科技奖励3项；项目部分成果被企业应用实现产值8093万元，获取利润447万元；项目培养毕业硕士生18名，培养博士生（在读）1名；项目组成员获准后续国家级科研项目2项；项目组主要成员2人晋升副教授职称。项目重点解决了2个关键技术问题：（1）揭示了水压作用下冰积土坝料宏细观渗流变形耦合效应；（2）建立了水压作用下冰积土宏细观渗流变形耦合本构关系。项目在宏观受力条件下冰积土坝料细观组构变化规律、冰积土坝料土石坝渗流变形稳定性研究方面有一定创新、科学研究和推广应用价值。