掏槽爆破作用下振动波形预测及影响分区确定

Prediction of vibration waveforms and the determination of influence zones under the action of tunnel cutting blasting

为研究隧道掘进过程中掏槽爆破对既有建筑物的影响,构建地表质点爆破振动波形预测函数,引入基于爆破振动波形理论的影响区域划分方法。基于等效球形药包理论,结合萨道夫斯基公式和爆破振动频率预测公式,将拟合系数与等效振源强度函数中的工程参数建立联系,构建适用于实际工程的爆破振动波形函数。依托现场监测数据,验证引入方法的可靠性。最后,分别以质点峰值振速、振动位移作为标准划分爆破振动影响区域。根据计算结果,掌子面在邻近被保护对象水平距离D=50 m时应采取相应的控制爆破措施。

To study the impact of cut hole blasting on existing buildings on the surface of the tunnel during tunneling,a surface particle vibration waveform prediction function was constructed,and a method of dividing the affected area based on the vibration waveform theory was proposed.First,starting from the theory of ground vibration waveform caused by the equivalent spherical charge blasting in a semi-infinite elastic medium,considering the characteristics of ground vibration in the actual medium,combining the Sadolfsky formula and the frequency prediction formula similar to its form,the fitting coefficient and equivalent the coefficients in the source intensity function are connected to construct a surface vibration waveform function suitable for actual engineering;Then the correctness of the surface particle vibration waveform function is verified through on-site monitoring data;Finally,the peak vibration velocity and cumulative displacement of the particle are used as the control standards.Divide the area of influence.According to the calculation results,appropriate controlled blasting measures should be taken when the horizontal distance between the tunnel face and the protected object is D=50 m.