大连地区路基软土冻融循环三轴试验研究  

Experimental study on soft soil subgrade under freeze-thaw cycles by triaxial tests in Dalian area

作　　者：江宗斌[1] 姜谙男[1] 

机构地区：[1]大连海事大学道桥所,辽宁大连116026

出　　处：《大连海事大学学报》2013年第3期117-120,共4页Journal of Dalian Maritime University

基　　金：国家自然科学基金资助项目(51079010);大连市交通科技项目(2011-10);中央高校基本科研业务费资助项目(2012TD015)

摘　　要：以大连海事大学附近黄浦路路基土为研究对象,通过SLB-1型三轴试验仪进行不同冻融次数的三轴压缩试验,研究冻融对土的特性的影响.在不同围压(0-800kPa)和不同冻融循环(0-20次)的组合条件下,获得含水率、主应力差-应变、强度参数的变化规律.试验结果表明:相同冻融次数时,剪切强度随围压增大而增大;相同围压下土的内摩擦角、黏聚力和剪切强度随冻融次数的增加呈现先减小后增大的趋势;含水率随冻融次数的增加先升高后降低.转折点对应冻融次数在7次左右.采用超固结效应机理对冻融过程特性变化进行分析.Take subgrade soil from Huangpu Road near Dalian Maritime University as research object, compression tests were carried out in different confining pressures and different times of freezing-thawing cycles using SLB-1 triaxial apparatus, and the effects of freezing-thawing on subgrade soil were studied . Under the condition of combination of different confining pressures（0 - 800kPa） and different times of freezing-thawing cycles （0 ~ 20）, the change law of moisture content, principal stress differ- ence-strain and strength parameter is obtained. Results show that under the same times of freezing-thawing cycles, shear strength increases with increasing of confining pressure. Under the same confining pressure, internal frictional angle, cohesive strength and shear strength present the tendency of reducing first and then increasing with the increase of the times of freezing-thawing cy-cles, however moisture content presents the tendency of increas- ing first then reducing with the increase of the times of freezing- thawing cycles. The turning point is about in the position of 7 times. Over consolidation effect mechanism is used to analyze the characteristic change of frozen-thaw process.

关 键 词：路基土 冻融循环 静三轴压缩实验 强度参数 

分 类 号：TU411[建筑科学—岩土工程]