摘要
扁铲侧胀试验过程以扁铲探头的贯入过程为基础,而贯入过程本身可能会对测试位置的土体造成一定的扰动,从而对试验结果产生影响。但目前关于扁铲探头贯入过程引起的土体宏细观变化特征尚不清楚。进行了扁铲探头贯入过程的颗粒流数值模拟,探讨贯入过程中土体颗粒的位移分布和孔隙率变化特征。结果表明,扁铲探头贯入过程中以周围土体的水平位移为主,对称分布在探头两侧,并近似呈半椭圆形向外扩散,影响范围距探头侧面可达220 mm,而探头中下部周围土体很窄范围内产生向下的竖向位移分布;探头周围土体在贯入过程中表现出一定的可逆性剪胀和不可逆剪胀,同时探头贯入对土体产生的影响与土体上覆有效压力及初始密实状态有关。
The flat dilatometer test(DMT)is based on the first blade penetration process,and the blade penetration may cause a certain disturbance to the soil at test location,which may further lead to the affection of test results.However,the characteristics of the macro and mesoscopic changes of soil caused by the penetration process of dilatometer penetration are still unclear.Numerical simulation of the DMT blade penetration into sand by particle flow code(PFC)was carried out,and both displacement distribution and porosity change characteristics of soil particles during the penetration process were studied.The results show that the horizontal displacement of the surrounding soil is dominant during the dilatometer penetration process,which is symmetrically distributed on both sides of the blade,and spreads out approximately in a semi-elliptical shape,and the influence range can reach 220 mm from the side of blade.A downward vertical displacement distribution is generated in a very narrow range of the soil around the lower part of the blade.The soil around the blade shows a certain degree of reversible dilatancy and irreversible dilatancy during the penetration process,and the influence of blade penetration on soil is related to the overburden effective pressure and the initial density of soil.
作者
葛娟
刘培成
陈忠清
吕越
祁娅颖
Ge Juan;Liu Peicheng;Chen Zhongqing;Lv Yue;Qi Yaying(School of Civil Engineering,Shaoxing University,Shaoxing Zhejiang 312000,China;Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province,Shaoxing Zhejiang 312000,China)
出处
《科技通报》
2021年第4期109-114,共6页
Bulletin of Science and Technology
基金
浙江省公益技术应用研究计划项目(No.2016C33052)
关键词
扁铲侧胀试验
贯入过程
颗粒流
数值模拟
砂土
the flat dilatometer test(DMT)
penetration process
particle flow code(PFC)
numerical simulation
sand
作者简介
葛娟(1996-),女,硕士研究生,主要从事岩土工程方面的科研工作;通信作者:陈忠清(1984-),男,博士,讲师,主要从事岩土工程及工程地质方面的科研与教学工作。E-mail:Q_CHEN_YK@163.com。
