Research and Analysis on the Influence of Small Clear Distance Drilling and Blasting Method on the Existing Tunnel Structure

Abstract

In order to study the vibration influence of tunnel drilling and blasting method on the built tunnel with small clear distance, taking the intersection of Zhuhai Dahengqinshan No. 1 tunnel and Zhuji urban rail tunnel as the engineering background, we used ABAQUS finite element software to conduct numerical simulation analysis on the influence of different blasting loads on existing tunnels with small clear distance in Zhuji tunnel construction. The following conclusions were drawn: the blasting construction of the tunnel under construction had the greatest impact on the vault of the existing tunnel; when the peak load was reduced by half, the stress value, vertical displacement, and resultant velocity of Mises were also reduced by half, which indicates that reducing the peak value of blasting load appropriately can ensure the safety of tunnel construction. When the peak load is 2.7 MPa, the measured and simulated values were less than the resultant velocity limit required by the specification. In addition, the relative error between the measured value and the simulated value was less than 5%, indicating the accuracy of the numerical simulation.

Analysis of the vibration impact of railway tunnel blasting excavation on existing highway tunnels

“…Based on the blasting dynamic analysis and weighted double-shear strength criterion, Liu et al [1] studied the impact of ultra-close blasting on existing tunnels, and proposed the nearby blasting safety assessment and blasting scheme preference method. Huang et al [2] used ABAQUS to establish the Zhuji tunnel model, exploring the impact of different blasting loads on the constructed small-clearance tunnels. It concluded that the blasting construction of the under-construction tunnels had the greatest impact on the vaults of existing tunnels.…”