吕梁地区压实马兰黄土变形与抗剪强度特性  

DEFORMATION AND SHEARING STRENGTH CHARACTERISTIC OF COMPACTED MALAN LOESS IN LüLIANG REGION

作　　者：胡长明[1] 梅源[1] 王雪艳[1,2] 

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]西安建筑科技大学华清学院,陕西西安710043

出　　处：《工程力学》2013年第10期108-114,共7页Engineering Mechanics

基　　金：陕西省科技攻关计划项目(2011k10-20);包头市科技计划项目(2011x1006)

摘　　要：针对吕梁地区压实马兰黄土的变形及抗剪强度特性开展了压缩及直剪试验研究,分析了初始压实度及初始含水量与抗剪强度指标之间的关系及其对土体压缩变形的影响,并基于割线模量法提出了压实马兰黄土在初始压实度及初始含水量变化时的变形修正公式。研究结果表明:压实马兰黄土初始含水量w及初始压实度K与粘聚力c及内摩擦角φ呈线性关系;在不考虑压实度及含水量的影响时,侧限压缩应变ε与垂直压力p关系可用ε=kpn表达;压实马兰黄土割线模量Esoi与K呈线性关系,且与1/w的关系曲线与抛物线非常相似。建立的压实马兰黄土在初始压实度及初始含水量变化时的变形修正公式可以用于吕梁地区压实马兰黄土填筑地基变形分析与计算。Compression tests and direct shear tests are carried out to study the deformation and the shearing strength characteristics of compacted Malan Loess in Liiliang region. Analyses are made on the relationship between the initial compaction degree as well as the initial water content and the shear strength indexes and on their effects on the compressive deformation of soil. By employing secant modulus method, the modified formula of deformation is established, when initial compaction degree and initial water content of compacted Malan loess has been changed. The results of the research show that the relationship between the initial water content w as well as the initial compaction degree K and the cohesion c as well as the angle of internal friction is linear, and that the relationship between the confined compression strain e and the vertical pressure p can be formulated as E=kpn without consideration of the effects of compaction degree and water content. Moreover, the results indicate that the relationship between the secant modulus Esoi and K is linear and that the relationship curve between Esoi and 1/w is similar to a parabola. Hence, when the initial compaction degree and the initial water content have been changed, the modified formula of deformation can be used to analyze and calculate the deformation compacted Malan Loess in Lliang region.

关 键 词：压实马兰黄土 抗剪强度 变形特性 割线模量 变形系数 

分 类 号：TU472[建筑科学—结构工程]