Mortar bolts are an important part of the tunnel support structure, and tunnel blasting can cause vibration hazards to the existing bolt support structure. According to the theory of blasting elastic wave theory, a dynamic mathematical model of bolts mortar bolts considering initial surrounding rock stress was established. Based on the blasting excavation example of the Longnan tunnel of a high-speed railway from Ganzhou to Shenzhen in China, the blasting dynamic response characteristics of mortar bolts in 0 ∼ 3 days, 3 ∼ 7 days, and 7 ∼ 28 days curing time under the blasting excavation of Classification-II, Classification-III, Classification-IV, and Classification-V surrounding rock were calculated and studied. The dynamic failure mechanism of mortar bolts with different curing time under blasting vibration was clarified. According to the limit axial force of the mortar bolts, the blasting safety distance and vibration velocity of the tunnel mortar bolts support structure was proposed.

砂浆锚杆是隧道支护结构的重要组成部分，隧道爆破会对既有锚杆支护结构产生振动危害。根据爆破弹性波理论，建立了考虑初始围岩应力的锚杆砂浆锚杆动力数学模型。以赣深高铁龙南隧道爆破开挖为例，研究了砂浆锚杆在0～3天、3～7天、7～28天养护时间下的爆破动力响应特性。对Ⅱ类、Ⅲ类、Ⅳ类、Ⅴ类围岩爆破开挖进行了计算研究。阐明了不同养护时间砂浆锚杆在爆破振动作用下的动态破坏机理。