全尾砂胶结充填体弹塑性本构模型实验研究  

Elastoplastic Constitutive Model Experiment of Full Tailings-cemented Filling Body

作　　者：吴姗[1,2] 宋卫东[1,2] 张兴才[3] 周家祥[3] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]金属矿山高效开采与安全教育部重点实验室,北京100083 [3]武汉钢铁集团矿业有限责任公司,湖北武汉430080

出　　处：《金属矿山》2014年第2期30-35,共6页Metal Mine

基　　金：国家自然科学基金项目(编号:51274023);教育部博士点基金项目(编号:20120006110022)

摘　　要：针对4种灰砂比、5种料浆浓度的全尾砂胶结充填体进行了单轴压缩实验,得出了其在单轴压缩条件下的物理力学特性。根据充填体单轴抗压强度分别选取灰砂比1∶6、1∶8,料浆浓度65%、70%的充填试块进行了4组不同围压下的三轴压缩实验,得到了充填体全应力-应变曲线及其物理力学参数。根据实验结果建立了充填体线弹-弹塑-塑性软化-理想塑性的本构模型,将充填体峰后应变软化阶段分为2种情况:在围压较小时,表现出明显应变软化,应力脆性跌落;在围压较高时,应变软化不明显,峰后直接进入塑性流动状态,残余强度与峰值强度差值减小。研究结果为充填体强度设计提供了理论依据。Uniaxial compression strength of full tailings-cemented filling body based on four gray sand ratio and five concentration of slurry were tested so as to obtain its physical and mechanical properties under uniaxial compression. Then, triaxial compression experiments under four different confining pressure were tested based on gray sand ratio of 1： 6,1： 8 and concentration of slurry of 65% ,70% to obtain stress-strain curve and physical and mechanical parameters of filling body. According to the experimental results, the constitutive model of linear elastic-elastic-plastic-plastic softening-ideal plastic was established, which divided the stage of post-peak strain softening of filling body into two cases： When the confining pressure is less, strain softening and brittle stress drop is showed obviously; When the confining pressure is higher, the stress-strain curve shows that strain softening is not obvious, which directly comes into the plastic flow after the peak, and the difference between residual strength and peak intensity decreases. This result provides a basis for strength design of filling body.

关 键 词：全尾砂胶结充填体 三轴压缩 全应力-应变曲线 弹塑性本构模型 

分 类 号：TD327[矿业工程—矿井建设] TD981