尾砂胶结含盐冻结充填体力学特性研究  

Study of mechanical properties of frozen saline cemented tailings backfill

作　　者：吴再海 纪洪广 姜海强 齐兆军 寇云鹏 WU Zai-hai;JI Hong-guang;JIANG Hai-qiang;QI Zhao-jun;KOU Yun-peng(Beijing Key Laboratory of Urban Underground Space Engineering,School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;Backfill Engineering Laboratory,Shandong Gold Mining Co.,Ltd.,Laizhou,Shandong 261441,China;Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]北京科技大学土木与资源工程学院城市地下空间工程北京市重点实验室,北京100083 [2]山东黄金矿业科技有限公司充填工程实验室,山东莱州261441 [3]东北大学深部金属矿山安全开采教育部重点实验室,辽宁沈阳110819

出　　处：《岩土力学》2020年第6期1874-1880,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51804063);国家自然科学基金重点项目(No.51534002)。

摘　　要：矿山充填开采正逐步向寒区甚至永久冻土区发展,这些区域含盐地下水分布非常广泛。同时,极端寒冷条件下往往需要向充填材料中加入一些防冻盐以防止料浆在输送过程中发生冻结。通过室内测试分析了-6℃环境下不同盐分(Na Cl)膏体充填体力学特性(强度和初始弹性模型)随时间演化特征。利用单轴压力机测得了龄期为7、28、90 d膏体充填体的强度和初始弹性模量,结果表明NaCl的加入会降低冻结充填体的强度,其影响程度取决于胶结料类型。试样的强度随着养护时间的增加而增大。此外,不论盐分浓度、养护时间和胶结料类型,试样的强度与初始弹性模量之间存在显著的线性关系。该研究结果可以为寒区含盐膏体充填技术的开展提供一些依据。Backfill mining operations are increasingly being performed in cold regions or even permafrost areas.The water available for the preparation of mine backfill is often naturally saline.Further,in some extremely cold regions,anti-freezing agents are often used to avoid the freezing of the paste during the pipeline transportation.This study,the time-dependent evolution of uniaxial compressive strength and initial elastic modulus of cemented paste backfill(CPB)with different saline concentrations(NaCl)at-6℃was experimentally investigated.Uniaxial compressive tests were conducted on various CPB samples for different curing times(7,28 and 90 days).The results show that the strength of CPB decreases with the addition of NaCl.All of samples experience an increase in strength with increasing curing time,due to the ongoing cement hydration.Moreover,there exists an obvious linear relationship between the uniaxial compressive strength and the initial elastic modulus,regardless of salinity,curing time and binder type.The results of this investigation could provide some technical information for the implications for backfill practices in cold regions.

关 键 词：含盐膏体 冻结 强度 初始弹性模量 

分 类 号：TD853.34[矿业工程—金属矿开采]