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目前爆破震动荷载作用下地下围岩稳定性判别主要依靠单一强度因子的独立阈值稳定性判据,这类判据多为定性分析,没有同时考虑爆破震动三要素的综合作用效果,且未建立稳定性判据与巷道围岩破坏程度之间的定量关系,在实际工程应用中存在一定的缺陷和不足。通过建立爆破荷载作用下的不同类别巷道围岩有限元模型,提取巷道围岩的响应信号,基于小波变换理论建立时间能量密度函数分析巷道围岩响应信号的时、频域特征,进而将时间能量密度曲线与时间轴围成的面积TEDI作为评估爆破震动效应的判别指标,建立了TEDI与巷道围岩损伤程度的定量关系,为进一步完善基于小波能量理论的巷道围岩损伤预警体系奠定基础。
At present, the criterion of stability of underground surrounding rock under blasting vibration load relies mainly on the independent threshold stability criterion of single intensity factor. Such criteria are mostly qualitative analysis without considering the combined effect of the three elements of blasting vibration and not establishing stable The quantitative relationship between the criterion and the degree of damage to the surrounding rock of tunnel has some defects and shortcomings in the practical engineering application. Through the establishment of the finite element model of surrounding rock of different types of tunnel under the action of blasting load, the response signal of surrounding rock of tunnel is extracted, and the time and energy density function is used to analyze the time and frequency domain characteristics of the surrounding rock response signal based on the wavelet transform theory. As a discriminant index to evaluate the blasting vibration effect, the TEDI is established as a quantitative index of the damage degree of the surrounding rock of the roadway, which lays the foundation for further improvement of the early warning system of the surrounding rock damage based on the wavelet energy theory.