南水北调中线工程运行期膨胀土长期变形及稳定性分析  

Long-term deformation and stability analysis of expansive soil during operation period of Middle Route Project of South-to-North Water Diversion

作　　者：冯党 吴庚 张一楠 何宜霖 熊勇 何佳林 FENG Dang;WU Geng;ZHANG Yinan;HE Yilin;XIONG Yong;HE Jialin(Head Section,Middle Branch of China South-to-North Water Diversion Co.,Ltd.,Nanyang 473000,China;Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China)

机构地区：[1]中国南水北调集团中线有限公司渠首分公司,河南南阳473000 [2]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010

出　　处：《水利水电快报》2024年第7期29-34,共6页Express Water Resources & Hydropower Information

基　　金：水利部先进实用技术示范项目“伞型锚土体快速锚固技术”(SF-202201);中央级公益性科研院所基本科研业务费(CKSF2019199/YT);青年科学基金项目(51709016)。

摘　　要：南水北调中线工程运行数年后,部分膨胀土边坡渠段出现了长期变形问题。为掌握膨胀土渠坡长期变形规律,利用南水北调中线膨胀土边坡运行期长期监测资料,分析了膨胀土渠坡深层变形的长期发展特征及其与降雨的关系,揭示了膨胀土边坡深层位移长期发展的内在机理。借鉴土力学流变原理中剪切蠕变的负幂时间函数,分析了幂指数与蠕变衰减速率之间的关系,确定了边坡长期变形收敛与发散的判别阈值,提出了用于深挖方膨胀土边坡长期稳定状态的幂次判别法。选取典型膨胀土深挖方边坡,基于实测数据开展膨胀土边坡长期稳定状态评价。与后续实际运行状态对比表明,幂次判别法具有有效性。研究成果为膨胀土边坡稳定状态评价和运行维护提供理论与技术支撑。After several years of operation,the expansive soil slope of Middle Route of South-to-North Water Diversion Project had a long-term deformation problems in some canal sections.In order to grasp the long-term deformation law of expansive soil slope,the long-term development characteristics of deep deformation of expansive soil slope and its relationship with rainfall were analyzed by using the long-term monitoring data of expansive soil slope in the Middle Route Project of South-to-North Water Diversion,and the internal mechanism of long-term development of deep displacement of expansive soil slope was revealed.Based on the negative power time function of shear creep in the principle of soil mechanics,the relationship between power exponent and creep attenuation rate was analyzed,the threshold value of convergence and divergence of long-term deformation of slope was determined,and the power discrimination method for long-term stability of deep excavation expansive soil slope was proposed.The typical expansive soil deep excavation slope was selected,and the long-term stability state evaluation of expansive soil slope was carried out based on the measured data.The subsequent actual operation state results and the validity of the fractal dimension criterion were verified.The research can provide a theoretical and technical support for the stability evaluation and operation maintenance of expansive soil slope.

关 键 词：膨胀土 长期变形 幂次判别法 南水北调中线工程 

分 类 号：U213.14[交通运输工程—道路与铁道工程]