粘粒尾矿材料次固结特性影响因素研究  

Influence Factors on the Secondary Consolidation Properties of a Clay Tailings Mine

作　　者：陈锋[1] 胡晓明[1] 巫尚蔚 

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 [2]重庆大学资源及环境科学学院,重庆400044

出　　处：《土工基础》2017年第3期308-312,349,共6页Soil Engineering and Foundation

基　　金：国家自然科学基金(编号:51234004)

摘　　要：针对尾矿库扩容增高建设过程中遇到的固结问题,以粘粒尾矿材料为试验材料开展一维固结试验,研究加荷比、干密度、预压荷载大小及预压时间对粘粒尾矿材料的次固结系数的影响。研究表明:在固结应力为600kPa之前加荷比会对次固结系数有影响,600kPa以后几乎没有影响;次固结系数随着干密度的增大而增大;经过预压之后,试样沉降量明显小于未处理的试样,预压效应在固结应力为100~800kPa时起作用,当固结应力大于800kPa时,预压处理效应消失;预压时间在一定范围内对次固结系数影响较大,当达到一定的时间时,这种时间效应逐渐消失。最后,研究试验材料的次固结系数与压缩指数间的关系,研究表明二者之间可以用线性关系式表示。The consolidation related concerns were raised during a height increase of a tailing dam for its capacity expansion. Asa a result, one dimensional consolidation tests were conducted on the cohesive tailing dam materials. The objective of the tests is to investigate various impact of potential influence factors on the secondary consolidation properties of the cohesive tail- ing dam materials. These factors are： loading ratio, dry unit weight, magnitude of preloading and duration. The results indi- cate that, the loading ratio has some effect on the coefficient of secondary consolidation when the confining pressure is less than 600 KPa; The coefficient of secondary consolidation does not change when the confining pressure is greater than 600 KPa. The coefficient of secondary consolidation increases with the dry unit weight of the sample, after the preloading, the settlement is significantly less than samples without preloading. The influence of the preloading on the coefficient of the secondary consolida- tion has effect when the confining pressure is within the range of 100 KPa to 800 KPa. The preloading effect is not obvious when the confining pressure is greater than 800 KPa. The preloading duration has effect on the coefficient of the secondary con- solidation when the time is less than a threshold value. After this value, the preloading effect is not obvious. It is also conclu- ded that the relationship between the coefficient of secondary consolidation and the compression index can be statistically repre- sented by a linear regression formula.

关 键 词：尾矿 次固结 加荷比 干密度 预压 

分 类 号：TU411[建筑科学—岩土工程]