昆明地区压实红黏土蠕变特性研究  

Rheological Properties of the Compacted Red Clay in Kunming Region

作　　者：孙希望 李良吉 杨果岳[2] 徐运龙 

机构地区：[1]中铁二院昆明勘察设计研究院有限公司,昆明650000 [2]湘潭大学土木工程与力学学院,湖南湘潭411105

出　　处：《土工基础》2018年第1期50-54,58,共6页Soil Engineering and Foundation

基　　金：国家自然科学基金资助项目(51508489);昆明市科技计划资助项目(2014-01-A-G-02-3049)

摘　　要：红黏土的工程特性地区差异很大,针对昆明地区高填方压实红黏土,对其在不同压实度、不同含水率与不同竖向荷载条件下进行了长期单轴蠕变试验来研究其蠕变特性。研究结果表明：在压实度大于92%时,压实度对蠕变影响不大;对在同一压实度情况下,当含水率低于21.26%时,压实红黏土蠕变随含水率的增大而变化较小,当含水率超过这一值时,蠕变随含水率的增大而增长较快。为了进一步分析含水率对压实红黏土蠕变的影响,引入次固结系数,发现同一压实度下,在含水率15.83%~21.26%区间内存在沉降最小含水率,并通过建立蠕变模型,计算工后沉降量,确定其沉降最小含水率为18.33%,低于最优含水率20.77%。The engineering characteristics of red clay soils vary significantly in different regions.This paper presents a case history of the rheological properties of the compacted Red Clay under high fill in Kunming area.The long-term rheological tests were performed on samples with different degrees of compaction and different moisture contents.The following conclusions can be obtained from the test results：when the degrees of compaction are greater than 92%,the creep properties are not affected by the degrees of compaction.Under the same degree of compaction,when the moisture content is lower than 21.26%,the creep decreases with the increase of moisture content.The secondary consolidation coefficient is introduced in the study to further characterize the effect of moisture content on the rheological properties of the Red Clay.Under the same degree of compaction,a moisture content for the minimum settlement exists between 15.83%and 21.26%.A post construction settlement analysis model was developed considering the creep effect.It was found that the moisture content for the minimum post construction was 18.33%,whereas,the optimum moisture content for the compaction was 20.77%.

关 键 词：压实红黏土 压实度 蠕变模型 沉降最小含水率 

分 类 号：TU443[建筑科学—岩土工程]