动力排水固结法加固软土路基的模型试验研究  

Study of model tests of soft soil foundation by dynamic drainage consolidation

作　　者：薛茹[1] 李广慧[1] 

机构地区：[1]郑州航空工业管理学院,郑州450015

出　　处：《岩土力学》2011年第11期3242-3248,共7页Rock and Soil Mechanics

基　　金：2010年河南省科技攻关项目(No.102102210372)

摘　　要：软土中孔隙水压力长消规律是研究动力排水固结法加固机制及控制施工效果的关键因素。针对这一问题,设计了动力排水固结法加固软土路基的模型试验装置并进行了试验。试验模拟某高速公路现场条件,按不同锤重、不同落距、不同锤底面积等工况分别进行。重点研究了动力排水固结法加固软土路基时,夯击击数、夯击能、夯锤重量及落距等参数在不同组合情况下土体不同深度处孔隙水压力的长消规律。研究表明,夯击能相同的情况下增加夯击次数将导致孔隙水压力消散减慢,但保持夯击能不变的情况下增加锤重比增加落距的加固效果好;高夯击能能使孔隙水压力有较大增幅,相应的加固范围也会增大。为了促使孔隙水压力消散,施工时宜采取多遍夯击,逐遍增加夯击能的施工方法。In the process of soft foundation treatment using dynamic drainage consolidation,the growth and dissipation of pore water pressure play the decisive role.It is not only primary bases to control the construction schedule,but also is an important parameter to ascertain the strengthening depth and evaluate the reinforcement effect.So the model test,it simulated an expressway site conditions,is carried out with test apparatus designed by ourselves.In order to comprehend the variation of pore water pressure under different parameter combination,these parameters include tamping times;tamping energy;hammer weight;hammer bottom’s area and fall distance,the test is divided into several groups.These tests include the pore water pressure of the same or different depths under different or the same tamping times,the pore water pressure of the same depth with different combinations between tamping energy and hammer weight and so on.Research shows that,when keeping tamping energy invariant,increasing tamping times will slower dissipation of pore water pressure.And increasing hammer weight will be more effective than increasing fall distance.The high tamping energy can make pore water pressure has bigger amplitude,and the corresponding reinforcement range will increase.In order to speed up dissipation of pore pressure,construction procedure should adopt the method of ＂multiple tamping,and successive increase tamping energy＂.

关 键 词：动力排水固结 模型试验 孔隙水压力 软土路基 地基处理 

分 类 号：TU447[建筑科学—岩土工程]