Safety Analysis of the Tunnel Excavation Blasting and the Supporting

Abstract

Wuhan east lake tunnel project is located in the national 5 a grade within the east lake scenic area, and it is a key project of Wuhan, which has a higher requirement on safety civilization construction. Using traditional unidirectional drivage CRD construction method in tunnel construction, significant impact on construction period, dismantling temporary arch suppression and middle wall for large drivers for construction, improve the efficiency of production of tunnel excavation. The removal of temporary inverted arch will affect the integrity of the original upper arch closed bracket and disturb the surrounding rock and soil around the excavation guide hole. Regarding the tunnel excavation blasting scheme design, through the dynamics of FLAC3D numerical simulation calculation, the dynamic response to blasting two-dimensional elastic-plastic time history analysis, the research analyzed the lining in the early dynamic response under blasting vibration, based on the control of blasting vibration measurement experiment, and through the measured results, the safety of the surrounding rock resistance to vibration is evaluated according to the construction under the condition of dismantling temporary inverted arch bottom drift of CRD method.