论文部分内容阅读
通过分析岩石在高温下的弹塑性力学性质,建立了二维非线性热—固耦合数学模型;在考虑岩石热物理性质随温度变化的基础上,采用有限元方法,对煤炭地下气化过程中顶底板的热应力场进行了数值计算;进而研究了层状岩石在高温环境中的热应力场和易破坏区域的分布情况。模拟结果表明,在气化煤层燃空区的顶底板和燃空区两侧煤壁的顶底板都受到较大的拉应力作用,其中两侧的煤壁顶底板在拉、压应力交界处还导致剪应力的产生。因此,大的拉应力和剪应力的位置是岩石容易破裂的关键位置。
By analyzing the elasto-plastic mechanical properties of rock at high temperature, a two-dimensional nonlinear thermo-mechanical coupling model is established. Based on the change of thermal physical properties of rock with temperature, the finite element method The thermal stress field of roof and floor is numerically calculated. Then the distribution of thermal stress field and fragile zone in layered rock under high temperature is studied. The simulation results show that the roof and floor of the coal wall on both sides of the burned area and the gas floor of the gasification coalbed are subjected to a greater tensile stress, in which the top and bottom of the coal wall on both sides of the coal seam at the junction of tension and compressive stress Lead to the generation of shear stress. Therefore, the location of large tensile stress and shear stress is the key to the rock rupture.