爆破施工对紧邻既有隧道影响的研究

Research on the Influence of Blasting Construction on the Adjacent Existing Tunnel

以某高速公路隧道改扩建为工程背景,在实测的基础上,根据理论力学合力矩原理,对炮孔进行简化,应用ANSYS/LS-DYNA建立爆破数值模型,对比实测数据和模拟结果显示,简化后的数值模型能够较准确地反映实际的爆破振动情况。综合结果显示,当新建隧道与既有隧道平行时,爆破作业产生的振动最大为垂直于隧道走向的水平方向,当净距为18.15~25.48m,在远离既有一侧进行爆破开挖,最大单响药量为24kg时,爆破振动对既有隧道的影响在安全允许范围内。

Taking the reconstruction and expansion of a highway tunnel as the engineering background,on the basis of actual measurement,according to the theory of resultant moment,the blasting hole was simplified,and ANSYS/LS-DYNA was applied to establish the blasting numerical model.Compared with the measured data and simulation results,the simplified numerical model can reflect the actual blasting vibration accurately.The comprehensive results show that when the new tunnel is parallel to the existing tunnel,the maximum vibration generated by blasting operation is perpendicular to the horizontal direction of the tunnel.When the clear distance is 18.15~25.48m,blasting excavation is carried out far away from the existing side,and maximum single blow blasting charge is 24kg,the influence of blasting vibration on the existing tunnel within the safe permissible range.