摘要
高心墙堆石坝心墙和岸坡混凝土垫层接触部位错切变形大,常通过设置接触黏土来增强这一位置的变形协调性和抗渗透破坏能力。已有试验研究表明,黏性土和混凝土接触面一般在大剪切变形下的抗渗透破坏能力增强,但其机理尚不明确。本文对这一机理展开研究。对黏性土-混凝土接触面进行了一组剪切-渗流试验,并对其中一个试样在不同阶段于接触面附近取样,利用X射线断层扫描术(即XCT扫描)试验对其进行微观结构扫描。通过图像处理软件对试样进行三维结构重建,并提取了在试验过程中不同相对位移下接触面附近土样的表观孔隙率分布。通过对表观孔隙率的分布及XCT扫描的典型截面图像分析,研究了黏性土-混凝土接触面在一定固结压力下发生大剪切变形后抗渗能力增强的机理。
The position of the core wall of the high-core rockfill dam and the concrete cushion on the bank slope are the key positions that are prone to seepage failure.The impermeability of this position is often enhanced by set-ting up contact with cohesive soil.According to an experimental study,the impermeability of the contact surface of cohesive soil and concrete is enhanced under large shear deformation,but the mechanism remains unclear.To study the mechanism,this paper takes soil samples near the contact surface in different stages of the cohesive soil-concrete interface shear-seepage test to perform X-ray computed tomography scanning,and then conducts three-di-mensional reconstruction using image process program.The soil near the contact surface at different stages of the test is analyzed.The pore distribution and apparent porosity change of the sample reveal the mechanism of the enhanced impermeability of the cohesive soil-concrete interface under large shear deformation.
作者
于际凯
刘千惠
YU Jikai;LIU Qianhui(Xuzhou Water Conservancy Building Design and Research Institute,X uzhou 221116,China;China Coal Research Institute,Beijing 100013,China)
出处
《中国水利水电科学研究院学报（中英文）》
北大核心
2022年第5期422-427,共6页
Journal of China Institute of Water Resources and Hydropower Research
基金
中国煤炭科工集团有限公司科技创新创业资金专项重点项目(2022-ZD002)。
关键词
黏性土-混凝土接触面
剪切
渗流
微观结构
XCT扫描
clayey soil-concrete interface
shear
seepage
micro-structure
X-ray computed tomography scan-ning
