中文摘要：

针对深埋圆形隧洞全断面爆破开挖,分析了岩体开挖瞬态卸荷力学过程及引起的围岩应力和应变能瞬态调整机制,讨论了瞬态卸荷动力效应的影响因素。计算结果表明,开挖岩体应变能越大、应变能释放速率越快,岩体开挖瞬态卸荷动力扰动越强烈。基于此,提出了依据炮孔周围爆生裂纹分布判断掌子面上主应力方向,各圈炮孔按掌子面上应变能密度由高到低的顺序分段起爆的施工期岩爆防治方法。该方法通过改变炮孔起爆网络显著地降低了岩体开挖瞬态卸荷的动力效应,可广泛用于水电、矿山、交通等行业深埋洞室贯通爆破。

英文摘要：

For excavation of a deeply-buried circle tunnel by the method of full-face blasting, the process of transient release of in situ stresses on excavation faces is briefly introduced. The stress and strain energy adjustments in the surrounding rock masses induced by the transient process are analyzed, and the main factors affecting the dynamic effects are also discussed. The results show that the dynamic effects of the transient release of in situ stresses are positively correlated to the strain energy magnitude of the rock masses to be excavated and the release rate of the strain energy. By controlling the dynamic effects caused by the transient release of in situ stresses, a prevention method for rock bursts during the construction process is proposed. In this prevention method, the direction of in situ stress on the blasting work face is first predicted according to the distribution of blast-induced cracks around a blasthole, and then the blastholes in a round are sequentially detonated in the order of the strain energy density from high to low. By changing the initiation sequence of blasting, the dynamic effects due to the transient release of in situ stresses are significantly reduced. The proposed prevention method can find widespread application in the holing blasts of deep-buried opening excavation in hydropower, mining and transport industries.