充填膏体蠕变硬化特征与机制试验研究  

Experimental study of creep hardening characteristic and mechanism of filling paste

作　　者：陈绍杰[1,2] 刘小岩[1] 韩野[3] 郭宇航[1] 任凯强[1] 

机构地区：[1]山东科技大学矿山灾害预防控制省部共建国家重点实验室培育基地,山东青岛266590 [2]安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,安徽淮南232001 [3]山东科技大学材料科学与工程学院,山东青岛266590

出　　处：《岩石力学与工程学报》2016年第3期570-578,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51474134);教育部新世纪优秀人才支持计划(NCET–13–0880);山东省自然科学基金重点项目(ZR2013EEZ001)~~

摘　　要：为研究充填膏体的蠕变硬化特性,对采用特定配比制成的充填膏体试样进行含水率与密度、单轴压缩与单轴压缩蠕变、电镜扫描等系列试验研究。结果表明:试验试样含水率及密度呈正态分布,离散性小,其单轴压缩强度与密度和含水率均无相关性;蠕变过程中,充填膏体随应力水平提高水平间弹性阶段应变率减小而瞬时变形模量增大,每个应力水平加载2,4及8 h时,瞬时变形模量增长率分别为1.17×105%,1.21×105%,1.23×105%,平均为1.20×105%;加载时长为2,4和8 h时,充填膏体有效模量强化系数分别为0.813 9,0.873 7,0.911 8,平均为0.866 5;蠕变过程中试样内部结构调整趋于压密闭实、裂纹扩展发生偏转汇聚,蠕变硬化大于损伤;充填膏体在加载时长为2,4及8 h时,蠕变系数分别为1.06,1.16及1.20,平均蠕变系数为1.14。In order to explore the creep hardening characters of filling paste,a series of experiments were launched with specific compositions,including the water content and density determination experiments,the uniaxial compression experiment and creep experiment and the scanning electron microscopy. The results show that water content and density of the samples comply with the normal distribution with small discrepancy. The water content and density have no correlation with the strength of filling paste. The strain rate at the elastic stage decreases and the instantaneous deformation moduli of specimens increase with the increasing of stress level. The instantaneous deformation moduli under loading period of 2,4 and 8 h are 1.17×105%,1.21×105% and 1.23×105% respectively,and the average growth rate is 1.20×105%. The enhancing factors of effective moduli are respectively 0.813 9,0.873 7 and 0.911 8 under 2,4 and 8 h loading,and the average enhancing factor of effective moduli is 0.866 5 which is 1.14 times of the factor in uniaxial compressive experiment. The internal structure of filling paste specimens becomes well-distributed and dense under slowly loading process. The adjustment of internal structure of filling paste occurs and there are triangular strengthening cracks inside under long-term bearing,leading to the increasing of loading capacity. The adjustment of internal structure becomes more obvious with longer loading period. The creep coefficients of filling paste under 2,4 and 8 h loading are 1.06,1.16 and 1.20 respectively,and the average creep coefficient is 1.14.

关 键 词：采矿工程 充填膏体 短时蠕变试验 瞬时变形模量 有效模量 硬化机制 

分 类 号：TD82[矿业工程—煤矿开采]