工程爆破中减震孔的隔震机理与效果研究
发布时间：2018-09-08 18:25
【摘要】：当今,工程爆破已经在实际工程中运用的越来越多,爆破的震动效应对周围环境的影响也越来越突出,如何减小爆破振动对周围环境的危害日益受到工程师的关注。本文以长沙地铁一号线汽车北站为工程背景,从理论分析、数值模拟和监控数据统计分析三个方面对减震孔的隔震原理、隔震效果进行研究。(1)从理论上对减震孔的隔震原理进行分析。爆破地震波传播过程是爆破地震波与传播介质的相互作用的过程,传播介质的物理力学性质对爆破地震波的传播产生很大的影响。在传播介质中打减震孔就相当于改变传播介质的物理性质,使爆破地震波发生折射、反射,从而削弱继续向前传播爆破地震波能量。本文采用节理刚度描述的界面模型来研究应力波与非完全固结介质界面之间的相互作用,把介质界面看成具有位移间断的线弹性半空间的接触面。最终得到透射系数小于1,说明爆破地震波在经过减震孔时能量有损失。(2)运用Midas/GTS软件,模拟得出减震孔具有一定的隔震作用,其减震率为10%～20%,并且减震孔的排数越多隔震效果越好,孔距越小隔震效果越好,当爆心距为10m减震孔的隔震效果较好,其减震率可以达到16%左右,随着爆心距的增加,其隔震效果逐渐减小,当爆心距为25m时减震率只有6%,所以减震孔的爆心距在10m～25m时隔震效果比较好。(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,运用MATLAB软件对爆破监控的数据进行回归分析。可知有减震孔的震动速度小于无减震孔的震动速度,其减震率在10%-20%之间,并且随着爆心距的增大,减震孔对爆破振动的隔震作用越来越不明显,有减震孔的拟合曲线与无减震孔的拟合曲线几乎重合。最后对Midas/GTS数值模拟的数据与现场监控的数据对比,得出两种结果接近,说明Midas/GTS数值模拟软件对模拟爆破振动是可信的。
[Abstract]:Nowadays, engineering blasting has been used more and more in practical engineering, and the effect of blasting vibration on the surrounding environment is becoming more and more prominent. How to reduce the damage of blasting vibration to the surrounding environment has been paid more and more attention by engineers. In this paper, based on the engineering background of Changsha Metro Line 1 Automobile North Station, the isolation principle of the shock absorber hole is analyzed from three aspects: theoretical analysis, numerical simulation and statistical analysis of monitoring data. The isolation effect is studied. (1) the isolation principle of the shock absorber hole is analyzed theoretically. The propagation process of blasting seismic wave is a process of interaction between blasting seismic wave and propagating medium. The physical and mechanical properties of propagating medium have a great influence on the propagation of blasting seismic wave. It is equivalent to change the physical properties of propagation medium to make blasting seismic wave refraction and reflection so as to weaken the energy of further propagation of blasting seismic wave. In this paper, the interface model of joint stiffness is used to study the interaction between the stress wave and the interface of the incomplete consolidated medium. The interface of the medium is regarded as a contact surface in a linear elastic half-space with displacements. Finally, the transmission coefficient is less than 1, which indicates that the energy of blasting seismic wave is lost when it passes through the damping hole. (2) by using Midas/GTS software, it is found that the shock absorption hole has a certain isolation effect. The more the number of holes, the better the isolation effect, and the better the isolation effect is, the smaller the hole spacing is, the better the isolation effect is. When the core distance is 10 m, the isolation effect is better, and the damping rate can reach about 16%, with the increase of the blast center distance. The isolation effect decreases gradually, and the damping rate is only 6 when the blasting center distance is 25m, so the isolation effect of the blast center distance of the damping hole is better at 10m~25m. (3) based on the least square principle, the blasting monitoring data of the North Station of Changsha Metro Line 1 are used. The data of blasting monitoring are regressed by MATLAB software. The results show 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%. With the increase of the distance between the blast centers, the isolation effect of the damping hole on the blasting vibration is less and less obvious. The fitting curve of the damped hole almost coincides with the fitting curve of the non-damped hole. Finally, by comparing the data of Midas/GTS numerical simulation with field monitoring data, two results are obtained, which shows that Midas/GTS numerical simulation software is reliable for simulating blasting vibration.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U231.3;U455.6
，
本文编号：2231328
[Abstract]:Nowadays, engineering blasting has been used more and more in practical engineering, and the effect of blasting vibration on the surrounding environment is becoming more and more prominent. How to reduce the damage of blasting vibration to the surrounding environment has been paid more and more attention by engineers. In this paper, based on the engineering background of Changsha Metro Line 1 Automobile North Station, the isolation principle of the shock absorber hole is analyzed from three aspects: theoretical analysis, numerical simulation and statistical analysis of monitoring data. The isolation effect is studied. (1) the isolation principle of the shock absorber hole is analyzed theoretically. The propagation process of blasting seismic wave is a process of interaction between blasting seismic wave and propagating medium. The physical and mechanical properties of propagating medium have a great influence on the propagation of blasting seismic wave. It is equivalent to change the physical properties of propagation medium to make blasting seismic wave refraction and reflection so as to weaken the energy of further propagation of blasting seismic wave. In this paper, the interface model of joint stiffness is used to study the interaction between the stress wave and the interface of the incomplete consolidated medium. The interface of the medium is regarded as a contact surface in a linear elastic half-space with displacements. Finally, the transmission coefficient is less than 1, which indicates that the energy of blasting seismic wave is lost when it passes through the damping hole. (2) by using Midas/GTS software, it is found that the shock absorption hole has a certain isolation effect. The more the number of holes, the better the isolation effect, and the better the isolation effect is, the smaller the hole spacing is, the better the isolation effect is. When the core distance is 10 m, the isolation effect is better, and the damping rate can reach about 16%, with the increase of the blast center distance. The isolation effect decreases gradually, and the damping rate is only 6 when the blasting center distance is 25m, so the isolation effect of the blast center distance of the damping hole is better at 10m~25m. (3) based on the least square principle, the blasting monitoring data of the North Station of Changsha Metro Line 1 are used. The data of blasting monitoring are regressed by MATLAB software. The results show 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%. With the increase of the distance between the blast centers, the isolation effect of the damping hole on the blasting vibration is less and less obvious. The fitting curve of the damped hole almost coincides with the fitting curve of the non-damped hole. Finally, by comparing the data of Midas/GTS numerical simulation with field monitoring data, two results are obtained, which shows that Midas/GTS numerical simulation software is reliable for simulating blasting vibration.
【学位授予单位】：长沙理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U231.3;U455.6
，
本文编号：2231328
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