减振孔参数对降振效率影响研究

发布时间：2018-03-31 07:42

本文选题：爆破　切入点：爆破振动　出处：《湖南科技大学》2016年硕士论文

【摘要】：爆破振动危害控制是爆破工程领域和学术界研究的重大前沿课题。减振孔作为一项有效控制爆破振动技术被广泛应用于保护边坡、基坑、建(构)筑物,获得了良好的经济效益和社会效益。当爆破地震波传经减振孔时,会发生反射、绕射和透射,波的强度将被削弱。关于减振孔的研究甚少,减振孔参数设计缺乏理论指导。因此,研究减振孔降振效率的影响因素对指导爆破振动控制中减振孔参数优化设计具有极其重要的意义。本文通过对比研究减振孔参数,利用数值计算、模拟试验、数值模拟等研究手段分析减振孔参数对降振效率的影响,取得成果如下:(1)通过分析空孔中应力波波场,研究应力波在单个空孔附近的传播规律,根据稳态波方程及边界条件,得出单个空孔(圆孔)直径和泊松比与减振因子RF之间的一般关系。(2)通过建立预留不同参数下的混凝土减振孔模型,对比分析了不同参数及布置方式条件下的试验数据,得出了减振孔参数对降振效率影响的基本规律。试验结果表明:随着减振孔孔径D、排数n、超深H的增大,减振率也会增大。而对于减振孔爆心距e、孔距a则恰好相反。(3)实测表明,振动径向主频一般都会小于垂直方向主频,垂直方向上主频相对于水平方向主频会更高。(4)运用有限元ANSYS/LS-DYNA数值模拟软件,建立不同减振孔参数(孔径D,排数n,孔距a,爆心距e,孔深h、超深H等)的爆破源—减振孔模型,分析应力波在减振孔的前后观察点振速峰值变化情况,通过数值计算,图表对比分析,表明数值模拟结果和现场模拟试验结论基本一致。
[Abstract]:The hazard control of blasting vibration is an important frontier subject in the field of blasting engineering and academic circles. As an effective blasting vibration control technology, vibration absorber hole is widely used to protect slope, foundation pit, and build (construct) structures. Good economic and social benefits are obtained. When the blasting seismic wave passes through the damping hole, reflection, diffraction and transmission will occur, and the intensity of the wave will be weakened. The design of damping hole parameters lacks theoretical guidance. Therefore, it is of great significance to study the factors affecting the damping efficiency of the damping hole to guide the optimum design of the damping hole parameters in the blasting vibration control. In this paper, the parameters of the damping hole are compared and studied. By means of numerical calculation, simulation test, numerical simulation and so on, the effect of damping hole parameters on the vibration reduction efficiency is analyzed. The results are as follows: 1) by analyzing the stress wave field in the hollow hole, the propagation law of the stress wave near a single hole is studied. According to the steady wave equation and boundary conditions, the general relationship between the diameter of a single hollow hole and Poisson's ratio and the vibration absorption factor RF is obtained. The experimental data under different parameters and layout conditions are compared and analyzed, and the basic law of the influence of the damping hole parameters on the vibration reduction efficiency is obtained. The experimental results show that: with the increase of the aperture D, the number of n and the super depth H of the damping hole, The measured results show that the radial main frequency of vibration is generally smaller than the vertical main frequency. The main frequency in the vertical direction is higher than that in the horizontal direction. The finite element ANSYS/LS-DYNA numerical simulation software is used to establish the blasting source-damping hole model with different damping hole parameters (aperture D, row number n, hole spacing a, burst center distance E, hole depth h, ultra deep H, etc.). The variation of peak value of stress wave at the observation point before and after the vibration absorption hole is analyzed. Through numerical calculation and chart comparison, it is shown that the numerical simulation results are basically consistent with the field simulation test results.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TB41

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