多年冻土地区L型挡土墙土压力(冻胀力)的分析与试验  

Experiment and Analysis of the Earth Pressure (Frost Heaving Forces) on L-Type Retaining Wall in Permafrost Regions

作　　者：梁波[1] 王家东[1] 严松宏[1] 黄志军[1] 杨泉[1] 

机构地区：[1]兰州铁道学院土木建筑学院,甘肃兰州730070

出　　处：《冰川冻土》2002年第5期628-633,共6页Journal of Glaciology and Geocryology

基　　金：铁道部科技开发计划项目 (2 0 0 1G0 0 1 A 0 1)资助

摘　　要：为适应多年冻土区土体冻胀过程所产生的较大变形的特性 ,缩短施工进程 ,减少扰动时间 ,在青藏铁路格拉段选择了一个试验工点进行了L型悬臂挡墙的初步验证性试验研究 .通过对L型挡墙的受力模式分析 ,确定了对粗颗粒填料不考虑冻胀力的土压力设计控制值 .通过与现场实测土压力分布规律的对比 ,探讨了土压力与冻胀力的关系 .In order to adapt itself to the greater deformation of the earth frost heaving process in permafrost regions, to shorten the construction time and to reduce the time of earth disturbed as soon as possible, a test\|constructing site was chosen to do a experiment study about designing and using L\|type retaining wall in the section from Golmud to Lhasa of the Qinghai-Tibetan Railway. By analyzing the models of forces upon L\|type retaining wall, controlling designing values of earth pressure are confirmed without considering the frost heaving forces, because the filling materials are thicker grains. The relationship between earth pressures and frost heaving forces are initially studied.\;Through analysis and tests, under the precondition of having not gone through a freezing and thawing cycling period, the following initial conclusions can be drawn.\;(1) When coarse\|grained heat\|insulated material is used, several analysis model provided in this paper are entirely feasible to design retaining wall. But the model of sliding along a frozen surface is better.\;(2) For frost heaving soil, without considering earth pressure to design retaining wall based on frost\|heaving force is also feasible. The critical problem is to define frost-heaving ratio.\;(3) When the measured earth pressure of hypothetical wall\|back conforms to general parabola\|distribution law, it is suggested that the design and test are reliable.\;(4) From test results and analysis, it is predicted that as long as the filling is non\|frost heaving soil and there is a width enough to keep warm, the influence of frost heaving will decrease to the minimum. Other measurements (including measuring the contact\|surface pressure between filling and nature soils) show there is no frost\|heaving phenomenon, indicating the validity of heat\|insulated material.

关 键 词：多年冻土 L型挡墙 土压力 冻胀力 铁路 

分 类 号：U213.152.2[交通运输工程—道路与铁道工程] U213.14