论文部分内容阅读
爆破参数如爆破安全药量、起爆时差等计算的准确性对城市隧道低振速控制爆破至关重要,在逐孔微差爆破振动叠加情况下其计算十分复杂和困难.以南方某城市隧道工程为背景研究上述问题的解决方法:实测各段雷管样本起爆延时范围;进行现场单孔单自由面爆破实验获得不同药量-时间振动曲线;再利用MATLAB程序,根据每段不同延时范围,将两单孔曲线按相邻段起爆的多个微差间隔进行不同振动叠加,选择其中最大振速的合成曲线与单孔振动曲线按下一相邻孔的微差间隔进行新的振动合成,最终得到8孔微差掏槽爆破后的累积叠加曲线.以此与现场实测振动曲线比较,发现第二临空面形成时间在起爆70ms以内;爆破药量设计以起爆70ms前的微差爆破合成振速为依据,确定了安全药量计算方法,在试验隧道控制振速1.0cm/s条件下安全药量为1.0kg,现场监测表明全部爆破振速均在要求指标之内.
The accuracy of blasting parameters such as blasting safety dose, initiation time difference and so on is of vital importance to the low-speed controlled blasting of urban tunnels, which is very complicated and difficult to calculate in the case of superimposed blasting of holes by millisecond blasting vibration.With a city tunnel project As the background to solve the above problems: to measure the detonation delay range of each detonator sample; to carry out single-hole single free-surface blasting experiment on site to obtain different dose-time vibration curves; and then use the MATLAB program, The two single-hole curves are superimposed by different vibrations at a plurality of micro-differential intervals detonated by the adjacent sections, the synthetic curve with the maximum vibration speed is selected, and the single-hole vibration curve is pressed to generate a new vibration synthesis according to the micro-difference interval of an adjacent hole, Finally, the cumulative superposition curve of 8-hole micro-undercut blasting was obtained.Through comparison with the measured vibration curve in the field, it was found that the formation time of the second temporary airfoil was within 70ms of detonation, and the design of blasting dose was combined with the micro- Based on which the safety dose was calculated. The safety dose was 1.0kg under the condition that the control tunnel velocity was 1.0cm / s. The on-site monitoring showed that all the blasting vibration velocity Within the required indicators.