坝体心墙与垫层混凝土结合处黏土碾压和防渗现场试验

Field test study of filling and penetration of highly plastic clay located between the dam core wall and cushion concrete

对糯扎渡水电站心墙与垫层混凝土结合部位的高塑性黏土进行现场碾压与防渗试验,采用沉降量、灌水法、环刀法等多种方法对黏土质量进行检测对比,探讨高塑性黏土的压实机制以及颗粒级配、铺土厚度、碾压遍数等不同施工工艺参数及不同参数的组合对压实与防渗效果的影响,提出结合施工工艺参数,黏土现场压实质量控制应以沉降差或沉降率为主、渗透性可以采用压实度来进行控制,该方法可有效地保证填筑质量,加快施工进度,并可对有压实机防渗要求的类似工程的质量控制、检测和评价提供参考,具有重要的实用价值。

The compaction and penetration tests of highly plastic clay,located between the dam core wall and cushion concrete in Nuozhadu hydropower station,are performed.The compaction mechanism and the influence of different construction technological parameters such as grain composition,filling thickness and compaction times,etc.are discussed by the field roller compaction and penetration test.On the basis of the test,the optimal technological parameters and quality control specification of the given project are found by contrast tests for which various detection methods such as compaction settlement,watering method and cutting ring are adopted.And field compaction and penetration quality control method of highly plastic clay is put forward;namely,differential settlement and compaction is given priority but construction technological parameters must be considered at the same time.The method may insure filling quality effectively and quicken construction progress.And it also can provide scientific data,standards for the quality control,quality check,quality evaluation of the projects for which highly plastic clay soil is adopted as filling material.It has significant applicable value.