【摘要】 对围岩切应力与单轴抗压强度的比值、岩爆事件的空间分布、TBM掘进隧道的围岩稳定及超深井井壁稳定等问题的分析表明,静荷载理论在岩爆研究中的局限性是明显的。对于钻爆法开挖的硬岩隧道,岩爆应该是处于非均匀应力状态的围岩在爆炸加载波、卸载应力波及岩爆应力波多次扰动的情况下,裂纹发生大规模瞬时动力扩展的结果,这可以概括为岩爆的岩石动力学机理。卸载扰动在已开挖围岩表面附近将产生P波、S波和Rayleigh波,对围岩扰动最大的是P波和Rayleigh波。P波和Rayleigh波的性质、分布及衰减规律可以较好地解释地应力量级对岩爆的控制及岩爆事件的空间分布等。更多还原

【Abstract】 It is found out that the limitations of static load theory in rock burst research are apparent by ways of analyzing the ratio of maximum tangential stress at the opening to the unconfined compressive strength,the spatial distribution of rockburst events,the stability of surrounding rocks of tunnels excavated with TBM and the super-deep holes. To the tunnels excavated with drill and blast tunneling,rockburst should be the results of cracks propagating extensively in the twinkling of an eye after the surrounding rocks under the state of anisotropic stress are disturbed repeatedly by stress waves resulting from blasting,instant unloading and rock bursting. This may be summarized as dynamics mechanisms of rockburst. The types of stress waves resulting from the unloading disturbance in other blasting rounds are the same as those stemming from blast-loading disturbance,that is,P wave,S wave and Rayleigh wave. The disturbance of P wave and Rayleigh wave on surrounding rocks is apparent. The properties,distribution and attenuation of P wave and Rayleigh wave can reasonably explain the effect of geostress on rockburst and the spatial distribution of rockburst events.更多还原