以静力学、冲击动力为实验手段,得出煤在不同应变率荷载下的应力-应变关系。根据实验结果及煤体动态力学特征,通过改进朱-王-唐本构模型建立了体现煤体应变率效应、损伤特征的本构方程。将建立的方程嵌入有限元程序中对煤体在不同峰值冲击荷载作用下的损伤机理进行研究,研究结果表明:煤体在冲击荷载下出现层状间隔劈裂结构,煤体的劈裂损伤主要有2种形式:①由较大拉剪应力形成的“快速跃升式”损伤;②拉剪-压剪交替作用累积形成的“慢速阶梯式”损伤。
Stress-strain relations of coal were derived under various rates of strain by means of impact and static experi- ment. According to experimental results and the dynamic features of coal, the constitutive equations of coal strain-rate effect and damage characteristics were established by improving Z-W-T constitutive models. Embedding the established equation into finite element program and researching coal' s damage mechanism under impact loading of different peaks, the study reveals that the layered interval splitting structure appears when coal is splitting structure has mainly two kinds of forms. One is "zooming" damage led by "stepped" damage led by compression-tension shear damage accumulation under impact loading, whose tension shear, the other is