Influence of Ground Water on Blasting Construction of Adjacent Tunnel

During the construction of a mountain tunnel, water-rich strata are often encountered. Current research on the influence of groundwater on the blasting construction of the adjacent tunnel is not in-depth enough. Based on the Yingpanshan tunnel project of Huali Expressway in Yunnan Province, China, this paper analyzes multi-factor couplings such as blasting dynamic load, large-section excavation, groundwater and adjacent construction. An adjacent construction model with a size of 80×80×50m is established by COMSOL Multiphysics software. Considering the change of permeability and elastic modulus of the model, the influence of blasting construction on the adjacent construction is reflected by the vibration velocity of the existing tunnel lining. The results show that the impact of groundwater on the safety of the adjacent structure is mainly related to the permeability, and its influence degree increases with the water pressure. In the water-rich stratum with high permeability of rock mass, it is necessary to pay attention to the influence of groundwater on the safety of adjacent blasting construction.