Investigation of long-wavelength elastic wave propagation through wet bentonite-filled rock joints  

作　　者：Ji-Won Kim Song-Hun Chong Jin-Seop Kim Geon-Young Kim 

机构地区：[1]Disposal Performance Demonstration R&D Division,Korea Atomic Energy Research Institute,Daejeon,34057,Republic of Korea [2]Department of Civil Engineering,Sunchon National University,Suncheon,57922,Republic of Korea

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2023年第10期2496-2507,共12页岩石力学与岩土工程学报（英文版）

基　　金：funding support from the Nuclear Research and Development Program of the National Research Foundation of Korea(Grant Nos.2021M2E1A1085193 and 2020M2C9A1062949).

摘　　要：The saturation of the compacted bentonite buffer in the deep geological repository can cause bentonite swelling,intrusion into rock fractures,and erosion.Inevitably,erosion and subsequent bentonite mass loss due to groundwater inflow can aggravate the overall integrity of the engineered barrier system.Therefore,the coupled hydro-mechanical interaction between the buffer and rock during groundwater inflow and bentonite intrusion should be evaluated to guarantee the long-term safety of deep geological disposal.This study investigated the effect of bentonite erosion and intrusion on the elastic wave propagation characteristics in jointed rocks using a quasi-static resonant column test.Jointed rock specimens with different joint conditions(i.e.joint surface saturation and bentonite filling)were prepared using granite rock discs sampled from the Korea Underground Research Tunnel(KURT)and Gyeongju bentonite.The long-wavelength longitudinal and shear wave velocities were measured under different normal stress levels.A Hertzian-type power model was used to fit the wave velocities,and the relationship between the two fitted parameters provided the trend of joint conditions.Numerical simulations using three-dimensional distinct element code(3DEC)were conducted to better understand how the long-wavelength wave propagates through wet bentonite-filled rock joints.

关 键 词：Engineered barrier system Bentonite erosion and intrusion Jointed rock mass Long-wavelength elastic wave velocity Quasi-static resonant column test Three-dimensional distinct element code(3DEC) 

分 类 号：P64[天文地球—地质矿产勘探]