减震孔对爆破地震的隔振效果研究

发布时间：2018-05-12 12:28

本文选题：减震孔 + 爆破振动　；参考：《长沙理工大学》2015年硕士论文

【摘要】：在爆破工程中,有效地控制或减小爆破震动对保护区域的破坏,为人们所关注。本文以长沙地铁一号线汽车北站基坑开挖爆破为工程背景,从理论分析、数值模拟和现场监控数据三个方面研究减震孔对爆破地震波的隔振原理、以及减震孔诸因素对隔震效果的影响规律。(1)从理论上分析减震孔的隔振原理。减震孔隔振效应实际上是应力波在介质中传播时人为衰减的复杂问题。将爆破应力波从减震孔孔底分成上部应力波和底部应力波,应力波在减震孔孔壁产生反射、透射和绕现象,减震孔能部分阻隔其传播,加速应力波能量衰减,减小对保护区的破坏。(2)运用Midas/GTS软件,模拟得出,减震孔具有一定的隔振作用,利用Excel软件拟合减震孔在不同参数组合时的隔振效果规律计算公式,得出了如下的结论:增加减震孔的孔径、排数,减少孔距可有效的隔振,随着减震孔与主炮孔的间距的增加,减震孔的隔振效果越差。(3)利用长沙地铁一号线汽车北站爆破监控数据,以最小二乘原理为基础,对爆破监控的数据进行回归分析。可知有减震孔的振动速度小于无减震孔的振动速度,其减震率在10%~20%之间,减震率随爆心距的增大而减小,减震孔的减震效果在爆破近区较好。最后对Midas/GTS数值模拟的数据与现场监控的数据对比,表明两种结果大致吻合,说明爆破振动数值模拟所讨论的减震孔诸因素对隔振效果的影响规律符合实际。
[Abstract]:In blasting engineering, people pay more attention to effectively control or reduce the damage of blasting vibration to protected area. In this paper, based on the engineering background of excavation and blasting of foundation pit of Changsha Metro Line 1 Automobile North Station, the vibration isolation principle of shock absorber hole to blasting seismic wave is studied from three aspects: theoretical analysis, numerical simulation and field monitoring data. And the influence of various factors on the isolation effect of the shock absorber hole. 1) the isolation principle of the shock absorber hole is analyzed theoretically. The isolation effect of shock absorption holes is actually a complex problem of artificial attenuation of stress waves propagating in medium. The blasting stress wave is divided into the upper stress wave and the bottom stress wave from the bottom of the damping hole. The stress wave produces reflection, transmission and winding phenomenon in the wall of the damping hole. The energy of the damping hole partially blocks its propagation and accelerates the energy attenuation of the stress wave. Midas/GTS software is used to simulate the vibration isolation effect of the damping hole, and the Excel software is used to fit the formula of the vibration isolation effect of the damping hole when the different parameters are combined. The conclusions are as follows: increasing the aperture and number of shock absorption holes and reducing the spacing between the holes can be used to effectively isolate the vibration, with the increase of the spacing between the damping holes and the main gun holes. The worse the vibration isolation effect of the shock absorber hole is, the worse the vibration isolation effect is. (3) the blasting monitoring data of Changsha Metro Line 1 is used to analyze the blasting monitoring data based on the least square principle. It is known that the vibration velocity of the damping hole is smaller than that of the non-damping hole, and the damping rate is between 10% and 20%, and the damping rate decreases with the increase of the distance between the blast centers. The effect of the damping hole is better in the near area of blasting. Finally, the comparison between the data of Midas/GTS numerical simulation and that of field monitoring shows that the two results are in good agreement with each other, which indicates that the influence of various factors of shock absorption holes discussed in numerical simulation of blasting vibration on the isolation effect is in line with the actual situation.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU352.1;P315.9

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