Field study on stability of the surrounding rock of inclined shaft in thick gravel stratum of Yili's first coal mine

In order to study surrounding rock stability of inclined shaft in gravel stratum of Yili’s First Coal Mine, the field tests on surrounding rock in no water and water-rich section of air shaft and material well were done respectively.The results show that ① the surrounding rock of large section inclined shaft in no water gravel stratum is steady.Shed temporary support, reinforced concrete wall as a permanent support is an effective method of supporting.When driving in the use of excavators the whole section is dug, and temporary support in a timely manner.The length of temporary support according to the stability of surrounding rock to determine usually can be controlled in 20~30m.② The surrounding rock in water-rich gravel stratum is easy to instability.The combination support method of advanced support, temporary support and the permanent support should be adopted.Support should focus on water seepage or gushing water treatment face.The results can provide reference for Lili’s mine building programs.