Analysis Of Stability Of Surrounding Rock And Support Technology In Large Section Chamber Of Deep Well

After decades of mining for the coal resources in China, the shallow coal resources which are easily mined are exhausted, and the deep coal-mining has become an inevitable trend. For the large section chamber of deep well, because of its burial depth and large cross section, the influence of natural factors, engineering factors and human factors should be comprehensively considered in the supporting designs of the chambers. The excavation process of the chamber is a process which is closely related to the stress path of the project. In the construction process of the chamber, surrounding rocks are repeatedly disturbed. The stresses of the surrounding rocks are unceasingly redistributed, and the deformations of the surrounding rocks are constantly changed. Eventually, the stability of the surrounding rocks is greatly affected.In this paper, combined with the engineering geological data and the data of the laboratory tests, the supporting schemes for the main drainage pump room in the second auxiliary shaft of Zhangji coalmine are numerically simulated by GTS. The change laws of the displacement field and stress field for the surrounding rock are analyzed, and the best supporting scheme is determined. Through the regular monitoring analysis on the convergence deformation of the surrounding rocks for the large section chambers of deep well, such as the ingate, the main pump room and the skip loading chamber of the second auxiliary shaft, it is known that the convergence deformations of surrounding rocks are relatively small. Through the analysis on the reinforced stress monitoring data of the skip loading chamber, it is known that the maximal compressive stress is on the position of the junction of the loading chamber and the shaft. Therefore, the support strength of the junction must be increased with the lining designs.In this paper, the loading chamber of the second auxiliary shaft of Zhangji coalmine is taken as an open and dynamic system. The dynamic response of the construction sequence, the excavation and the supporting is studied. The inherent law of natural factors, human factors and the stability of surrounding rock of the connected chambers in deep well is obtained. The results of this paper have an important guiding significance to solve the reliable support of the connected chambers in deep well, to prevent the damage of large cross section chamber effectively and to ensure the safe production of coal mine.