增强体复合土动弹性模量影响因素的研究  

Experimental study on factors influencing the dynamic elastic modulus of composite soil with different reinforcements

作　　者：曾国红[1] 白晓红[1] 张卫平[2] 孙晋 

机构地区：[1]太原理工大学建筑与土木工程学院,山西太原030024 [2]太原市建筑设计研究院,山西太原030012 [3]山西建筑职业技术学院,山西太原030006

出　　处：《水利学报》2009年第5期576-582,共7页Journal of Hydraulic Engineering

基　　金：国家自然科学基金资助项目(50578104);山西省自然科学基金资助项目(20041061);太原市专项基金资助项目(07010779)

摘　　要：通过水泥土、灰土、水泥砂浆3种增强体复合试样以及纯粉土试样的动三轴试验,研究了不同增强体对土体动弹性模量的影响,讨论了围压、置换率的影响程度。研究发现:增强体的设置使得土体的动弹性模量Ed及最大动弹性模量Edmax显著提高,复合试样的Ed和Edmax均随增强体刚度、置换率及围压的增大而增大。在各影响因素中,对水泥砂浆复合试样而言增强体设置对Edmax的提高程度最大;置换率增加对Edmax的提高程度随围压的增加而降低,且置换率对水泥土增强体复合土的影响最大,对水泥砂浆增强体复合土的影响最小;围压的增加对Edmax的提高程度随置换率的增加而减小,低置换率下围压的影响随增强体刚度不同而不同,随着置换率的提高围压对不同增强体复合土的影响逐渐趋于一致。文中同时给出不同增强体、置换率及围压对复合试样Edmax的影响规律表达式及各提高系数的回归公式。The effect of composite soil with different reinforcement, including the cement-soil, lime-soil and cement mortar, on dynamic elastic modulus of soil was experimentally studied by dynamic tri-axial test. It is found that the reinforcement remarkably elevate the soil dynamic elastic modulus Ed and maximum dynamic elastic modulus Edmax, and these moduli increase following the increase of stiffness of reinforcement, replacement ratio and confining pressure. Among these three kinds of reinforcement to be study, the effect of cement mortar reinforcement on elevating Edmax is the most. The effect of replacement increase on Edmax decreases as the confining pressure increases. The replacement ratio has the greatest effect upon the composite silt with cement-soil reinforcement but the smallest effect upon those with cement mortar reinforcement. The effect of confining prossure decreases as replacement ratio increases, and it varies by different reinforcement at lower replacement ratio. However, following the increase of replacement ratio the influence of confining pressure on different reinforced composite soils tends to a same level. The formulas of Edmax for different kinds of reinforcement with replacement ratio and confining pressure taken into account are given.

关 键 词：水泥土增强体 灰土增强体 水泥砂浆增强体 复合土 动荷载 动弹性模量 最大动弹性模量 

分 类 号：TU472[建筑科学—结构工程]