CAJ | 학술논문

在建的锦屏一级水电站蓄水后坝基(肩)软弱岩体在高水头作用下的弱化效应是工程建设十分关心的问题。为揭示这种弱化效应，提出一套岩体水压弱化效应的试验研究方法：采用岩体形成过程-力学条件模拟，力学参数控制三轴压缩全过程试验的手段制备岩体试件，对岩体试件进行现今天然状态与1～4 MPa静水压力的系列三轴压缩试验(围压为5，10，15，20，25，30 MPa)。试验结果及分析表明，在浅部低应力岩体中弱化效应十分显著，强度参数中的内摩擦因素 f 的弱化程度在13%以内，c 的弱化程度随静水压力的升高而急剧增大，最大可达100%；变形模量的弱化程度在20 MPa围压以下随静水压力的升高而增大，随围压的升高而减小，围压达到20 MPa后则基本无弱化现象。同时，建立了不同静水压力工况下岩体力学参数预测模型。这些成果已在锦屏一级水电站工程建设中得以应用，研究方法为岩体力学性能的试验室研究开辟了新的有效途径。
재건적금병일급수전참축수후패기(견)연약암체재고수두작용하적약화효응시공정건설십분관심적문제。위게시저충약화효응，제출일투암체수압약화효응적시험연구방법：채용암체형성과정-역학조건모의，역학삼수공제삼축압축전과정시험적수단제비암체시건，대암체시건진행현금천연상태여1～4 MPa정수압력적계렬삼축압축시험(위압위5，10，15，20，25，30 MPa)。시험결과급분석표명，재천부저응력암체중약화효응십분현저，강도삼수중적내마찰인소 f 적약화정도재13%이내，c 적약화정도수정수압력적승고이급극증대，최대가체100%；변형모량적약화정도재20 MPa위압이하수정수압력적승고이증대，수위압적승고이감소，위압체도20 MPa후칙기본무약화현상。동시，건립료불동정수압력공황하암체역학삼수예측모형。저사성과이재금병일급수전참공정건설중득이응용，연구방법위암체역학성능적시험실연구개벽료신적유효도경。
The weakening effect of high water head on dam foundation weak rock masses after impoundment for Jinping I hydropower station is a highly concerned subject for its engineering construction. A series of testing methods are suggested to reveal the weakening effect. Based on a geological process-mechanical mechanism simulation-mechanical parameter control theory,rock mass replica specimens can be prepared with complete process of triaxial compression test and used for hydro-mechanical coupling test. A series of triaxial compression tests with the confining pressures of 5,10,15,20,25,30 MPa are performed on the replica specimens under current natural state and hydrostatic pressures of 1-4 MPa. The result has shown that,the weakening effect is quite significant in the shallow low stress rock mass,the weakening rate of strength parameter f is within 13%,while the weakening effect of c increases dramatically up to 100%with the increasing hydrostatic pressure. The weakening rates of deformation modules increase with the increasing hydrostatic pressure when confining pressure is below 20 MPa,and decrease when confining pressure increases. However,when confining pressure exceeds to 20 MPa, the weakening effect is negligible. A prediction model of rock mass mechanical parameters is established according to the results. These achievements have already been applied to the engineering construction of Jinping I hydropower station,and the research techniques have opened up a new laboratorial way for research on rock mass mechanical properties.