考虑爆源特征的地面爆破震动波形预测与控制理论研究

The blasting vibration is an important subject in safety studies of engineering blasting. The waveform prediction is a key of blasting vibration control.The key problems in waveform prediction and control process of blasting vibration, such as the spherical charge blasting vibration focal mechanism, vibration source load and construction theory and technology of multi-parameter time-history vibration waveform function of the blasting vibration wave propagation on the surface, is studied in the case of ground rock blasting in this project. Thus,the spherical charge blasting vibration waveform prediction is achieved. The effects of the main blasting source factors, such as charge structure, charge length, explosive features,charge weight,multi-hole millisecond blasting and rock properties on blasting vibration are discussed, and the theoretical prediction of blasting vibration waveform controlled by many factors for single hole cylindrical charge blasting and millisecond blasting is strived to obtain. The multi-parameter prediction of cylindrical charge blasting vibration is also realized. The effects of blasting hole layout,numbers, interval time on millisecond blasting vibration characteristics are studied, and the waveform (frequency spectrum characteristic) control of blasting vibration are achieved. The theoretical results are verified and improved through the field and model tests and numerical simulation studies. The research results will further reveal the inherent mechanism of blasting vibration generation and propagation that is affected by explosion sources and mediums, and improve the existing single parameter prediction limitations of blasting vibration, increase the accuracy and reliability of blasting vibration prediction and control, and optimize the blasting design parameters. This would have a significant importance to both the theoretical study on prediction and control of blasting vibration effect and the engineering application.

爆破震动是爆破安全研究重要课题，波形预测是爆破震动控制关键。项目以地面岩石爆破为背景，研究爆破震动波形预测与控制过程中球状装药爆破震动震源机制、震源荷载以及地表震动传播波形时程函数构建理论与技术等关键问题，实现球形装药爆破震动波形预测。研究装药结构、装药长度、炸药性能、装药量、多孔微差爆破以及岩石特性等爆源主要因素对爆破震动的影响，建立由多因素控制的单孔柱状装药爆破和微差爆破震动波形预测理论，实现柱状装药爆破震动多参数预测。研究炮孔布设、数量、微差时间对微差爆破震动特性影响，实现爆破震动波形（频谱特性）控制。通过现场与模型试验及数值模拟研究，验证和完善理论分析结果。本成果将深入揭示爆源因素和传播介质等对爆破震动产生、传播影响的内在机理，改进目前爆破震动单参数预测的局限性，提高爆破震动预测和控制的精度与可靠性，优化爆破设计参数，这对爆破震动效应预测与控制理论研究和工程应用具有重要意义。

爆破震动波形预测与控制理论与技术是结构爆破震动效应预测与控制及爆破设计参数优化、实现爆破安全的关键。项目根据岩石中装药爆炸产生的弹塑性波的传播特点建立了弹塑性区发展的动力学模型，得到了岩石弹性区边界上的应力时程函数，提出了弹性区边界上爆破震动震源等效荷载的简单表达公式。根据Hoop点源理论和等效震源强度函数，得出了球腔压力源作用下地表质点震动波形函数，再根据萨道夫斯基公式、围岩的分级评分RMR和频率计算经验公式，构造出一个适用于实际工程且更加简洁的球形装药地表震动波形函数。利用叠加理论，得出柱状装药的地表震动波形函数。通过保角映射，建立了隧道掘进爆破引起的隧道未开挖段和已开挖段上方地表质点的震速计算方法。根据短柱装药爆破产生震动波的特点，研究了双孔微差爆破震动的局部放大效应，同时在短柱装药爆破的基础上研究了长柱装药特征及起爆方式对炸药爆破震动效应的影响，得到了长柱装药爆破下，药包长度、爆轰速度、埋置深度、起爆方式及围岩介质变化等对质点震速的影响，并利用萨氏公式拟合了柱状装药爆破下质点峰值速度。借鉴Blair的非线性群孔叠加理论，实现了振速波形函数的非线性叠加，得到了群孔微差爆破的地表振速波形函数，建立了一种新的群孔微差爆破地表震速波形预测方法，并通过振速波形函数探讨了微差时间和炮孔数量对地表振动的影响，得知合理的微差时间可以降低振速峰值，且使振动主频偏离保护对象的自振频率，并给出了合理微差时间的确定方法。首次采用电火花震源代替传统炸药，借助地下工程模型试验系统，开展了三维动态加载物理模型试验，测试了爆破地震波在围岩中的传播规律。成果能根据爆破震动安全判据和爆破参数在爆破前预测结构的安全性，并优化爆破设计，或通过技术手段（如微差爆破）改变震动波形，亦即改变震动频谱特性，实现震动效应控制。可以说，成果对工程爆破震动精细化控制理论与技术研究有着非常重要的理论和实用价值。