露天台阶爆破振动高程放大效应研究

发布时间：2018-05-21 06:13

本文选题：露天台阶爆破 + 高程差　；参考：《江西理工大学》2015年硕士论文

【摘要】：随着国民经济发展对矿产资源的需求日愈增长,许多矿山都已进入深部开采阶段,露采产量占采矿总量的比重大,且接近40%的露天边坡存在不同程度的稳定性隐患。随着开采深度增加,爆破振动随高程差的增加出现放大效应。为此,探讨爆破地震波在传播过程中的高程放大效应机理及衰减规律,在保证最终边坡安全的基础上寻求经济合理的爆破开采技术具有重要的理论意义和现实工程价值。本文结合波动理论研究露天台阶爆破振动的高程放大效应,通过对永平铜矿实测数据分析表明,露天台阶爆破中高程差对地震波传播的影响很大,萨道夫斯基公式没有考虑高程差的影响,在永平铜矿的实际应用中发现其衰减规律误差较大;爆破振动高程放大效应具有方向性,振幅在垂直方向的放大效应更明显且更加具有规律性,爆破振动的放大效应幅度也要大于水平方向和径向。基于能量原理研究了爆破地震波在不同频带范围的能量分布特征,发现在露天台阶爆破中,爆破地震波能量主要集中在0~40Hz范围,平均占总能量的96%,随着测点高程的增大,爆破地震波的能量在0~10Hz占的百分比越来越大,平均占总能量的51.46%。结合边坡对不同频率的谐波分量的响应特征,提出了露天台阶爆破振动高程放大效应机理是基于爆破地震波在不同介质层中折射与反射叠加导致的高程放大效应之上,随着高程的增大,局部边坡岩体与接近其固有频率的谐波分量的共振,进一步加剧了高程放大效应的效果。由于爆破地震波的这种传播叠加特性及层次分析法权重计算,得出露天边坡的地质条件对爆破振动高程放大效应的影响最大,边坡地质条件好的高程放大效应放大系数更高,不考虑地质条件的影响下,高程差对高程放大效应的影响权重最大。高程放大效应还与露天台阶爆破的爆破参数、起爆方式、爆心距、高程差等因素相关;随着高程的增加放大系数逐渐增大,但不是单调增大的,当高程达到106.67m时放大系数逐渐减小;随着爆心距的逐渐增加,放大系数随之减小;放大系数随着单响最大起爆药量的增加而单调增加;随着爆源比例距离的增加,放大系数随之增大,当爆源比例距离增大到0.06858时放大系数增长缓慢且逐渐趋于平稳。运用量纲分析的原理构建了考虑高程影响下的爆破振动速度变化阈值方程,结合实测数据计算相对误差。对比显示,使用改进后的爆破振动速度变化阈值方程对边坡质点振动速度进行预测时相对误差在9.91%~13.63%,要比萨道夫斯基公式预测的质点爆破振动速度(相对误差在27.64%~31.96%)更为准确。能更加贴切的反映爆破振动在永平铜矿露天边坡传播过程中的高程放大效应。
[Abstract]:With the increasing demand for mineral resources in the development of the national economy, many mines have entered the stage of deep mining, and the open pit production accounts for a large proportion of the total mining amount, and close to 40% of the open-pit slope has different degrees of stability hidden danger. With the increase of mining depth, the blasting vibration is magnified with the increase of height difference. Therefore, it is of great theoretical significance and practical engineering value to explore the mechanism of elevation amplification effect and attenuation law of blasting seismic wave in the process of propagation, and to seek economical and reasonable blasting mining technology on the basis of ensuring the safety of the final slope. In this paper, based on wave theory, the elevation amplification effect of open-air bench blasting vibration is studied. By analyzing the measured data of Yongping Copper Mine, it is shown that the height difference in open-pit bench blasting has a great influence on the propagation of seismic wave. In the practical application of Yongping Copper Mine, it is found that the error of attenuation law is large, the effect of blasting vibration height amplification is directional, the influence of height difference is not taken into account in the Saadolski formula. The amplification effect of the amplitude in the vertical direction is more obvious and regular, and the amplitude of the amplification effect of the blasting vibration is larger than that of the horizontal direction and the radial direction. Based on the energy principle, the energy distribution characteristics of blasting seismic waves in different frequency bands are studied. It is found that in open-pit bench blasting, the blasting seismic wave energy is mainly concentrated in the 0~40Hz range, which accounts for an average of 96% of the total energy. The energy of blasting seismic waves accounts for an increasing percentage of 0~10Hz, accounting for an average of 51.46% of the total energy. According to the characteristics of slope response to harmonic components of different frequencies, the mechanism of elevation amplification effect of open-air bench blasting vibration is proposed, which is based on the elevation amplification effect caused by the refraction and reflection superposition of blasting seismic waves in different media layers. With the increase of elevation, the resonance of local slope rock mass with harmonic components close to its natural frequency further intensifies the effect of elevation amplification. Because of the propagation superposition characteristic of blasting seismic wave and the calculation of analytic hierarchy process weight, it is concluded that the geological condition of open-pit slope has the greatest influence on the effect of blasting vibration elevation amplification, and the magnifying factor of elevation amplification effect with good geological condition of slope is even higher. Without considering the influence of geological conditions, the influence weight of elevation difference on elevation amplification is the largest. The effect of elevation amplification is also related to the blasting parameters, initiation mode, blasting center distance, height difference, etc. With the increase of elevation, the magnification factor increases gradually, but it is not monotonous. When the height reaches 106.67m, the magnification coefficient decreases gradually, the magnification coefficient decreases with the increasing of the center distance, the magnification coefficient increases monotonously with the increase of the maximum explosive quantity, the ratio of detonation source increases with the increase of the distance of detonation source. The magnification coefficient increases, and when the ratio of explosion source increases to 0.06858, the magnification coefficient increases slowly and tends to steady gradually. Based on the principle of dimensional analysis, the threshold equation of blasting vibration velocity change considering the influence of height is constructed, and the relative error is calculated by combining the measured data. The comparison shows that the relative error of the modified threshold equation of blasting vibration velocity in predicting the vibration velocity of the slope particle is 9.91 and 13.63. It is more accurate for the particle blasting vibration velocity (relative error is 27.64 ~ 31.96) to be predicted by Pizadowski's formula. It can better reflect the elevation amplification effect of blasting vibration in the process of open slope propagation in Yongping Copper Mine.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD854.2

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