| Shaft lining, as the role of main pathway between underground engineering and surface, which carries the security system of coal mine. Once shaft lining rupture, it will cause unrecoverable economic costs.In the late 1980 s to the early 1990 s, research institutes and production units have been playing close attention to the Huang-Huai coal mine area by virtue of the rupture of shaft lining was occurred. In recent years, the deformation of shaft linling in the multiple coal mine of Wan Bei area was occurred once again in the context of undirectly mining, some of which have seriously affected the safety in production, and even lead to shut down. So we can see that the deformation mechanism of shaft lining is complex, at present still not know clearly. Therefore, we carry forward the study on the deformation of shaft lining in thick unconsolidated layers and analyze its rupture mechanism, which both have theoretical significance and practical application value. Taking the deformation of main shaft lining in Qianyinzi coal mine for example, which locate in the south of Wan Bei Su Zhou, the reason of its deformation was revealed by using the method of numerical simulation and physical simulation. The main research results are as follows:(1)Through the systematic analysis of characters and other relevant factors of ruptured shaft lining of Wan Bei whole mining area, combined with the engineering geology and hydrologic geology conditions of industrial square in Qianyingzi coal mine, we conclude that the loss of the third and fourth aquifer in deep unconsolidated layers is the main factor of the rupture of shaft lining. Meanwhile, the ground settlement around the shaft is mainly caused by the loss of the third aquifer, and affected by the loss of the fourth aquifer is relatively small.(2)Base on effective stress principle and according to the surface subsidence, we roughly calculate the increment of effective stress caused by the loss of the third aquifer, simultaneously, combined with the increment of effective stress caused by the loss of the fourth aquifer, as a logic consequence, 2D numerical simulation was adopted to analyze interactions between shaft and its surrounding soil due to the loss of both the third and fourth aquifer. The result shows that there has a good linear relationship between maximum vertical additional force of shaft linling and the surface subsidence caused by the loss of the third aquifer, as well as water lowering of the fourth aquifer. At the same time, accumulation process of maximum vertical additional force of shaft linling presents lower and upper stages.(3)In order to study the size of additional force, strain, as well as spatial-temporal evolutional laws, we creatively design the simple indoor physical simulation experiment system of shaft linling, and findly the analysis results was achieved which were indential with numerical simulation. |
