尺寸效应对粉质黏土直接剪切试验强度指标的影响研究  

Study on the influence of size effect on the strength index of silty clay in direct shear test

作　　者：戴一鸣 韩中阳 余昌蔚 柳侃[2] Dai Yiming;Han Zhongyang;Yu Changwei;Liu Kan(Fujian Provincial Institute of Architectural Design and Research Co.,Ltd.,Fuzhou 350001,China;Key Laboratory of Geohazard of Hilly Mountains,Ministry of Land and Resources of China,Fujian Geological Engineering Survey Institue,Fuzhou 350002,China)

机构地区：[1]福建省建筑设计研究院有限公司,福州350001 [2]福建省地质工程勘察院国土资源部丘陵山地地质灾害防治重点实验室,福州350002

出　　处：《工程勘察》2021年第11期13-16,41,共5页Geotechnical Investigation & Surveying

基　　金：福建省2020年第一批建设行业科技项目(2020-K-71)。

摘　　要：本文通过现场人工取样,在相同室内试验条件下,对不同成因粉质黏土采用大体积试样和常规(规范法)试样进行了多组份的对比试验,试验研究成果发现试样体积效应对直接剪切试验结果有很大的影响,大体积试样土的强度指标c、φ值比常规(规范法)试验方法大,特别是黏聚力c值可相差一倍以上,坡积粉质黏土黏聚力c和内摩擦角φ值由于受颗粒组分的影响比常规(规范法)大一倍以上,研究成果对保证工程设计质量、安全和节约工程造价等具有重要的意义。Multi-component comparative tests were conducted on silty clay specimens of different origins using large-volume samples and conventional(standard method) samples obtained by manual sampling on site under the same indoor testing conditions. The results of the experimental study show that the outcome of direct shear test is influenced by the sample volume greatly;the strength index c and φ value of large-volume sample are larger than those of the conventional(standard method) test method, especially the cohesion c value can be more than doubled;and for the silty clay of slope deposit, the value of cohesion c and internal friction angle φ is more than twice as large as the conventional(standard method) due to the influence of particle composition. The study results are significant to ensure the design quality, construction safety and save engineering costs.

关 键 词：尺寸效应 粉质黏土 直接剪切试验 强度指标 对比试验 

分 类 号：TU41[建筑科学—岩土工程]