堆石料微侧壁摩擦力固结仪的研制与应用  

Development and application of an oedometer with negligible side-wall friction for rockfill materials

作　　者：王龙 朱俊高[1] 袁俊平[1] 陆阳洋 WANG Long;ZHU Jun-gao;YUAN Jun-ping;LU Yang-yang(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;Geotechnical Engineering Department,Nanjing Hydraulic Research Institute,Nanjing 210024,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]南京水利科学研究院岩土工程研究所,江苏南京210024

出　　处：《岩土工程学报》2022年第4期696-701,共6页Chinese Journal of Geotechnical Engineering

基　　金：长江水科学研究联合基金重点支持项目(U2040221);国家自然科学基金委员会-雅砻江流域水电开发有限公司雅砻江联合项目(U1865104);高等学校学科创新引智计划(111计划)(B13024)。

摘　　要：固结仪是研究堆石料长期变形特性最常用的仪器之一,但其应用受到侧壁摩擦力的限制。针对此问题,研制了一种加载稳定、可测量侧壁摩擦力的新型固结仪,介绍了该仪器的结构和工作原理。采用由互不接触的尼龙片组成衬垫贴于固结仪内壁的方法减小侧壁摩擦力。对风干堆石料进行固结试验,系统研究比较了衬垫层数为1~3层和厚度分别为0.3和0.5 mm时该方法的效果。试验结果表明,3层0.5 mm衬垫的效果最优;与无衬垫时相比,该方法下试样侧壁摩擦力平均下降91%,竖向应变是无衬垫时的1.2~1.8倍。将容器内壁覆盖3层0.5 mm衬垫作为减小侧壁摩擦力方法,对风干堆石料分别进行了使用该方法和无衬垫条件下的流变试验。结果表明,微侧壁摩擦力条件下试验结束时试样的竖向应变和次固结系数分别是无衬垫时的2.0和2.2倍。该仪器有效解决了侧壁摩擦力问题,提高了长期变形试验结果的可信性。The oedometer is one of the most commonly used apparatuses to investigate the long-term deformation behaviors of rockfill materials.However,the side-wall friction restrains its application.To overcome this limitation,an oedometer that can provide long-term and stable loading and measure the side-wall friction is developed.The main features of the apparatus are presented.To minimize the side-wall friction,the linings that consist of spaced and greased Polyamide plates are used to cover the oedometer wall.The consolidation tests are carried out to evaluate the performance of the anti-friction linings with layers in the range of 1~3 and with layer thickness of 0.3 and 0.5 mm,respectively.The best test results are obtained by using 3 layers of 0.5 mm-thick linings.At the same vertical stress,the side-wall friction is 91%smaller on average while the vertical strain is 20%~80%larger with 3 layers of 0.5 mm-thick anti-friction linings than that without linings.Therefore,the proposed method is chosen to reduce the side-wall friction,and the creep tests are carried out on air-dried rockfill materials.The test results show that the vertical strain at the end of the tests and the coefficient of the secondary consolidation are about 1.0 and 1.2 times larger with 3 layers of 0.5 mm-thick linings than those without linings.The apparatus substantially reduces the side-wall friction and improves the accuracy of creep test results.

关 键 词：堆石料 微侧壁摩擦力 固结仪 衬垫 流变试验 

分 类 号：TU431[建筑科学—岩土工程]