Statistic constitutive equation of top-coal damage for fully mechanized coal face with sub

Statistic constitutive equation of top-coal damage for fully mechanized coal face with sublevel caving

ZHAI Xin-xian

【期刊名称】《煤炭学报：英文版》 【年(卷),期】2008(014)001

【摘要】Under the action of abutment pressure in front of fully mechanized coal face with sublevel caving (CFSC), top-coal over CFSC deformed. In the process of whole de-formation of top-coal, it changed from continuum elastic mass to non-continuum plastic mass contained fissures, become a loose body. According to its bearing characteristics and mechanical properties, top-coal mass can be divided into four deformation zones along the winning direction of CFSC, i.e. initial stress zone, elastic zone, plastic zone and loose zone. Top-coal in plastic zone located in the post-peak zone of the stress-strain curve for top-coal. With equivalent strain principle of damage mechanics and mathemati-cal theory of statistic, combining the movement law of top-coal, set up a constitutive equa-tion with damage statistics for top-coal in different position in CFSC. The equation illus-trated the mathematical relationship among top-coal bearing capacity, horizontal confining pressure along the winning direction of CFSC and mechanical properties of top-coal mate-rial. The conclusions not only provide a basis for numerical computer simulations on damage deformation and failure