煤的动态力学本构模型  

Dynamic mechanical constitutive model of the coal

作　　者：付玉凯[1] 解北京[2] 王启飞[2] 

机构地区：[1]天地科技股份有限公司开采设计事业部,北京100013 [2]中国矿业大学(北京)资源与安全工程学院,北京100083

出　　处：《煤炭学报》2013年第10期1769-1774,共6页Journal of China Coal Society

基　　金：国家科技支撑计划资助项目(2012BAB13B02)

摘　　要：为揭示煤岩动态破坏机理,利用φ50 mm的分离式霍普金森压杆(SHPB)实验系统,对煤试样进行不同应变速率下的冲击加载实验,实验结果表明:煤体动态本构曲线前期就呈现出很强的非线性,初始弹性模量、屈服强度和极限强度都随应变率的增大而增大,塑性变形则是先增大后减小。根据动态本构曲线特征以及前人对本构模型的研究成果,运用弹塑性理论,建立了损伤体-黏弹性本构模型,模型的拟合曲线与实测动态本构曲线具有较好的一致性,拟合结果表明,煤体的动态力学性质对高低应变率的敏感性不同,对高应变率比较敏感,尤其是在300 s-1的应变率下,煤体的塑性流动最强,应力应变曲线产生了二类卸载(正斜率)。In order to reveal the mechanism of coal mass dynamic ple was made by φ50 mm split Hopkinson pressure bar （SHPB） damage , the impacting compression test of coal sam- experimental system under different strain rate. The experimental results show that the preliminary dynamic constitutive curve shows great nonlinear and initial elastic mod- ulus, yield strength and ultimate strength increase with the strain rate increasing, but plastic deformation first increases and then decreases. According to the dynamic constitutive curve characteristics and previous constitutive model re- search, damage visco-elastic constitutive model was introduced by using elastic and plastic theory. Dynamic constitutive model fitting curve has a good agreement with the measured curve, fitting results show that dynamic mechanical proper- ties of the coal have different sensitivity with high and low strain rate,it＇ s more sensitive to the high strain rate, espe- cially when the strain rate is 300 s-1 , the plastic flow of coal is strongest and the strain-stress curves exhibit the second kinds of unloading（ positive slope）.

关 键 词：霍普金森压杆 动态力学性能 本构模型 煤岩体 

分 类 号：TD313[矿业工程—矿井建设]