关键词: 盾构隧道, 超前致裂, 爆破损伤, 数值模拟

Abstract: Aiming at the problem of hard bedrock intrusion often encountered in the process of shield tunnel excavation，based on the characteristics of drilling and blasting method and shield tunnel excavation construction，a kind of advanced fracturing technology of shield tunnel horizontal single hole multiple blasting was proposed，and the numerical simulation research was carried out by ANSYS/LS-DYNA software. The results showed that using the complete restart technology and the initial volume fraction method，the subsequent blasting perfectly inheritsed the related variables such as stress and damage after the previous model blasting. After three times of horizontal single-hole blasting，the cavity radius at the hole bottom of the tunnel model was gradually expanded from 10 cm to 35 cm，the axial damage influence depth of the model was gradually expanded from 125 cm to 916 cm，and the radius of the radial damage influence was slowly expanded from 68 cm to the whole section. The damage to the surrounding rock of the tunnel was small，and the advanced cracking effect of the rock mass on the shield tunnel excavation route can be realized.

Key words: shield tunnel, advanced cracking, blasting damage, numerical simulation