摘要
对土工格栅与压实膨胀土的界面特性进行拉拔试验,筋材为高密度聚乙烯(HDPE)单向土工格栅,填土为南水北调中线工程新乡段的膨胀性泥灰岩风化土。结果表明:上覆荷载较大时,土工格栅的变形较明显,格栅刚体平动时的拉拔力更接近峰值,界面摩阻力的分布非均匀,且其均匀程度随拉拔力变化。较小上覆荷载下,峰值拉拔力时土工格栅刚体平动占筋土相对位移的比例较大,界面摩阻力分布较均匀。当界面摩阻力非均匀分布,可导致上覆荷载较大而其界面平均摩阻力反而较小。筋土相对位移1cm―2cm范围内,界面一般可达峰值强度,界面强度曲线可表达为线性函数。
A large-scale shear test apparatus with the carry out a series of pull-out tests, to investigate the filling of 600mm×600mm×600mm size is employed to interface behavior between the geogrid and compacted expansive soil. In the tests, the high density polythene （HDPE） uniaxial geogrid and the weathered expansive marlite in Xinxiang, the Middle Route of South to North Water Transfer Project （SNWT） are adopted. The results show that under the great vertical load, the geogrid deformation is great, the pull-out force approaches the peak value when the rigid motion occur more, the interface friction distributes nonuniformly, and the uniform degree varies with the pull-out force. While under the lower vertical load, the rigid motion of geogrid takes a great proportion to the total displacement, and the interface friction distributes uniformly basically. When the interface friction distributes nonuniformly, the average friction may decrease even under a greater vertical load. The peak strength of the interface can be attained with the relative displacement no more than 1cm--2cm. The strength curve of the interface can be described as a linear function.
出处
《工程力学》
EI
CSCD
北大核心
2009年第11期145-151,共7页
Engineering Mechanics
基金
国家"十一五"科技支撑计划重大项目(2006BAB04A10)
关键词
土工合成材料
膨胀土
拉拔试验
界面特性
单向土工格栅
南水北调工程
geosynthetics
expansive soil
pull-out test
interface behavior
uniaxial geogrid
south to north water transfer project
作者简介
汪明元（1972-），男，四川成都人，高工，博士生，从事加筋土、土石坝、膨胀土及土工数值方法研究（E-mail：wmy_90@163．com）；
龚晓南（1944-），男，浙江金华人，教授，博士，博导，从事复合地基、软土力学、基坑工程等教学研究（E-mail：xngong@hzcnc．com）
包承纲（1935-），男，浙江宁波人，教授，学士，博导，从事土工合成材料、膨胀土及离心机等教学研究（E-mail：bcgang@public．wh．hb．cn）
施戈亮（1983-），女，湖北新州人，硕士生，从事土工合成材料、膨胀土研究（E-mail：copperpea123@sina．com．cn）．
