Dynamic Responses of a Coupled Tunnel with Large Span and Small Clear Distance under Blasting Load of the Construction of Transverse Passage

In order to investigate the law of dynamic responses a coupled tunnel with large span and small clear distance induced by blasting load applied on excavation face new horizontal adit for vehicles, 3D finite element model was established based project Yonghe tunnel’s transverse passage in Guangzhou, China. The laws vibration velocity stress existing are systematically analyzed according numerical calculation results. results show that main affected area lining is lower arch waist facing blast, where both maximum tensile appear. horizontally radial (along axis passage) contributor resulting lining. distributed varying trend similar velocity, there appears be satisfied positive linear correlation between two indexes. When from 10 m, blasting-load-induced maximal only 2.96 cm/s 0.20 MPa, respectively, which far less than stipulated related technical code. A negative power exponential relationship peak also found. According this relationship, will exceed threshold standard, i.e., 8 cm/s, if decreases 5.9 m. To improve safety redundancy construction, suggested m under current construction scheme.