改性污泥复合材料时间效应三轴力学特性试验研究  

Research on time effect of modified sludge composites by triaxial tests on mechanical properties

作　　者：徐正明[1] 薛强[1] 赵颖[1] 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071

出　　处：《岩土力学》2011年第6期1713-1718,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目资助(No.50927904);湖北省重大科技开发项目资助(No.2008AC008);武汉市科技计划项目资助(No.201060723312;No.201050231025)

摘　　要：采用水玻璃、生石灰和絮状木质纤维作为污泥改性剂对城市污泥改性后,在不同养护龄期和不同改性剂配比下对改性污泥复合材料开展三轴固结不排水力学强度和破坏特征试验研究。改性剂设置3种配比5%、10%和15%,在相同围压下,养护5 d改性污泥复合材料破坏强度相对于原污泥相应地提高到1.25～1.426、1.12～1.33、1.2～1.5;养护10 d分别提高到1.33～1.45、1.154～1.35、1.56～1.67,改性剂配比5%和10%试验比15%硬化速度较快。养护10 d改性污泥在主应力差为20 kPa时,初始切线模量发生很大的突变,并且10%和15%组有3%～5%应变延时期。养护10 d时5%和10%配比的试样内摩擦角?值大于15%配比的试样,而黏聚力c值明显小于15%配比的试样。基于Konder应力-应变双曲线方程,利用主应力差渐近值作为归一化因子,建立改性污泥在三轴固结不排水条件下的主应力差-应变关系方程。Municipal sludge was modified by water glass,quick lime and flocculent fiber.The consolidated undrained triaxial tests were carried out for studying mechanical strength and failure characteristics of modified sludge composites.Three ratios of modifier were set as 5%,10% and 15%.After 5 days maintenance,compared with pure sludge,the failure strength of three modified sludge composites were increased by 1.25-1.426,1.12-1.33 and 1.20-1.50.After 10 days maintenance,the hardening speed of 5% and 10% modifier superior to that of 15%,the failure strength of three modified sludge composites were increased by 1.33-1.45,1.154-1.35 and 1.56-1.67 respectively.When principal stress difference reached 20 kPa after 10 days maintenance,initial tangent modulus have great mutations.Moreover,strain of modified sludge composites with 10% and 15% modifier have obvious 3%-5% delay period.The internal friction angle of 5% and 10% modifier are larger than that of 15%,whereas their cohesion much less than that of 15%.Based on stress-strain hyperbola proposed by Konde,the ultimate value of principal stress difference was adopted as the normalized factor.Meanwhile,the normalized stress-strain relationship of modified sludge was established under consolidated undrained triaxial tests.

关 键 词：改性污泥 时间效应 归一化方程 固结不排水三轴试验 抗剪强度 

分 类 号：TU443[建筑科学—岩土工程]