Application of cast-in-place pile protection method in excavating return air shaft fan drift
Because the return air shaft air tunnel generally adopts the construction technology of large excavation,the process has the disadvantages of large excavation area and large disturbance to the temporary shaft headframe,and the excavation process can not be carried out in parallel,resulting in long construction period.Therefore,reducing the excavation range of the air tunnel is a solution to the above problems.Based on the theory of slope protection,the supporting technology of cast-in-place pile is introduced into the construction of air return shafts air tunnel in Zhaoshipan Coal Mine.By the method of theoretical calculation and numerical simulation,the reasonable supporting parameters of cast-in-place pile are determined,which effectively solves the problem of slope protection during the excavation of air tunnel and greatly improves the construc-tion efficiency of air tunnel.
return air shaftfan driftcast-in-place pilefoundation pit excavationslope support