潘谢煤田13-1煤层煤岩冲击动力学性能及本构关系的建立

利用分离式Hopkinson压杆（SHPB）对潘谢煤田张集煤矿13-1煤层煤岩进行了不同应变率的冲击压缩实验，结果表明：煤岩动态应力-应变曲线表现出显著的应变硬化与应变率硬化等动态力学特性，煤岩峰值应力及动态弹性模量均随应变率提高而提高，得到了其动态强度与应变率的关系表达式。基于实验结果，通过改进朱－王－唐模型，建立了反映煤岩峰值应力前动态应力-应变关系的本构方程。通过数据拟合，获得了本构方程的相关参数，拟合参数表明：煤岩材料对高应变率的响应具有敏感性，在高应变率条件下气煤比无烟煤表征更明显的脆性特征，即气煤破坏应变更小。利用Fortran语言开发了VUMAT煤岩材料子程序，并对煤岩SHPB实验进行了数值模拟，模拟结果与实验结果吻合较好。

Mechanical properties and establishment of constitutive relation of coal rock in 13-1 coal seam from Panxie coalfield under impact load

The uniaxial impact compression test of coal rock in 13-1 coal seam from Panxie coalfield was conducted under different strain rates by using Split Hopkinson Bar (SHPB).The results show that the coal rock dynamic stress-strain curves take on dynamic characteristics such as strain hardening and strain rate hardening,and both of peak stress and dynamic elastic modulus of coal rock increase as the strain rate increases.The relationship between the peak strength of coal rock and strain rate was obtained from the test data.Based on experimental results,the constitutive equation was established by modifying Z-W-T constitutive model to reflect the dynamic stress-strain relationship of coal rock before peak stress.Being obtained through data fitting,the constitutive parameters indicate that coal rock is sensitive to the response of high strain rate,and under high strain rates,gas coal demonstrates a brittle feature more obviously than anthracite.VUMAT subroutine was developed by using Fortran language,and the SHPB experiment of coal rock was numerically simulated.The simulation results are in good agreement with those obtained by experiment.