干湿循环和含水率对尾砂压缩固结特性的影响研究  

Study on Consolidation Characteristics of Tailings with Different Moisture Content Under Dry-Wet Cycle

作　　者：王仲辉 王千福 田亚坤 伍玲玲 禹雪阳 张志军 WANG Zhonghui;WANG Qianfu;TIAN Yakun;WU Lingling;YU Xueyang;ZHANG Zhijun(School of Resource&Environment and Safety Engineering,University of South China,Hengyang 421001,Hunan,China;Hunan Engineering Technology Research Center of Mining Geotechnical Engineering Disaster Prediction and Control,Hengyang 421001,Hunan,China)

机构地区：[1]南华大学资源环境与安全工程学院,湖南衡阳421001 [2]湖南省矿山岩土工程灾害预测与控制工程技术研究中心,湖南衡阳421001

出　　处：《黄金科学技术》2022年第1期54-63,共10页Gold Science and Technology

基　　金：国家自然科学基金项目“吸湿—脱湿循环作用下铀尾矿的细观力学特性研究”(编号:51774187);“微生物注浆加固渗流场作用下的尾矿坝试验及机理研究”(编号:51804164);湖南省教育厅科研基金项目“基于介观结构及干湿循环作用的尾矿颗粒介质力学行为基础研究”(编号:20B496);湖南省研究生科研创新项目“干湿循环作用下细粒尾矿细观力学特性及变形机理研究”(编号:CX20210925);“微生物在致密型砂岩铀矿储层的迁移动力学研究”(编号:CX20210927);湖南省大学生创新创业训练计划项目“干湿循环条件下不同含水率的尾矿砂固结特性研究”(编号:202110555083)联合资助。

摘　　要：为辅助计算尾矿存积的沉降距离,指导放矿、尾矿子坝堆筑,提高尾矿坝的经济效益。研究干湿循环作用和含水率对湖南某金属尾矿库尾砂的压缩固结特性的影响。对含水率为10%、12%、14%、16%和18%的尾砂分别进行0~5次脱湿—吸湿—再脱湿试验,借助GZQ-1型全自动高压固结仪对试样开展了快速固结试验。研究结果表明:(1)相同条件下,孔隙比随着压力的上升而减少;(2)相同循环次数下,压缩系数随着含水率的上升而增加;相同含水率下,压缩系数随着干湿循环次数的增加呈“Λ”型变化;(3)不经干湿循环,固结系数随含水率的增加先上升后下降;在相同含水率条件下,随干湿循环次数的增加,固结系数的变化大致呈M型波动。前期循环过程受力以毛细水压力为主导,待颗粒运动稳定,尾砂孔隙结构发育完全,受力以黏结力和摩擦力为主导。With the improvement of mineral processing technology,the amount of tailings in storage is increasing year by year,and the particle size of tailings is getting finer and finer.However,such tailings have poor permeability,good water holding performance,long consolidation time and low mechanical strength.Such tailings often have problems such as difficult drainage,slow deposition and poor stability in the process of damfilling.In the complex climate and geographical environment,rainfall infiltration,water evaporation,repeated rise and fall of saturation line(that is,under the condition of dry-wet cycle),earthquake and so on will be encountered.These factors can not be ignored for the settlement of fine tailings pond.In order to help calculate the settlement distance of tailings deposit and guide ore drawing and tailings dam construction,the influence of dry-wet cycle and moisture content on the compression consolidation characteristics of tailings of a metal tailings pond in Hunan Province was studied.The tailings with water content of 10%,12%,14%,16%and 18%were subjected to 0~5 times of dehumidification-moisture absorption-dehumidification tests respectively,and rapid consolidation tests were carried out on the samples with the help of GZQ-1 automatic high-pressure consolidation instrument.The results show that:(1)Under the same conditions,the void ratio decreases with the increase of pressure.Without the dry-wet cycle,the void ratio of the sample at the optimum moisture content is the smallest,and the void ratio of natural moisture content,optimum moisture content and saturated moisture content changes in a U-shaped curve in turn.After the dry-wet cycle,the volume of tailings sample expands slightly,and the internal water-gas channel changes.After graded loading,the internal particles fill the pores,and finally the structure tends to be stable.(2)Under the same number of cycles,the compression coefficient increases with the increase of water content,Under the same moisture content,the compression coefficient chan

关 键 词：干湿循环 含水率 尾砂 E-P曲线 压缩系数 固结系数 

分 类 号：TD926.4[矿业工程—选矿]