铁路立体交叉隧道施工爆破震动响应研究

Study of construction blasting vibration response in railway interchange tunnel

文章通过建立不同交叉角度、净距和围岩条件的试验工况,对交叉段新建隧道施工爆破地震波引起的既有隧道衬砌的峰值速度进行分析,探讨了不同因素作用下立体交叉隧道施工爆破的动力响应。研究结果表明:处于既有隧道迎爆侧拱底和墙脚之间区域影响最为显著;除净距是上下交叉隧道最显著的影响因素外,随着交叉角度的增加,拱底速度峰值呈增大趋势,并且增长率逐渐加快;岩体越坚硬完整,爆破振动波传播衰减越慢,爆破地震波在传到既有隧道之前,出现峰值回升。

Through the establishment of experimental conditions with different cross angle,clear distance and rock conditions,the peak velocity of the existing tunnel lining caused by the seismic waves during the construction blasting of the new tunnel in cross section is analyzed to explore the dynamic response of construction blasting of interchange tunnel under the influence of different factors.The results are as follows：the maximum effect occurs between the arch bottom and wall foot facing the blasting side;in addition to the clearance of cross tunnel being the most significant factor,the peak velocity of bottom arch increases synchronously with the increase of crossing angle under the same clearance and the rate of growth accelerates gradually;the blasting vibration wave propagation decays slower in complete and hard rock,the peak velocity rebounds before blasting seismic waves reach the existing tunnel.