This paper on a criterion for rockbursts is focused mainly on the stress concentration and gradient change of the tangential stress of the surrounding rock. Two parameters are introduced into tunnelling strain rockburst prediction: the radius of the plastic zone and the radial stress at the elastoplastic junction after excavating the surrounding rock. A new rockburst criterion is proposed based on the mechanism for throwing-type rockbursts and catastrophe theory. Meanwhile, a new multi-factor index for identifying rockburst classification is given based on rockbursts in actual engineering. The results show that there is a certain correlation between strain rockbursts and the plastic-zone radius and radial stress of the surrounding rock, which can be estimated using the mechanical parameters and stress distribution before excavation, whereupon strain rockbursts can be predicted. By dividing the rockburst interval through a large number of rockburst examples, the accuracy of the criterion reaches 80·36%, and the accuracy for moderate-to-strong rockbursts reaches 83·33%.

中文翻译：

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将塑性区和切向应力引入隧道应变岩爆预测

本文针对岩爆的判据主要关注围岩切向应力的应力集中和梯度变化。隧道应变岩爆预测中引入两个参数：塑性区半径和开挖围岩后弹塑性接合处的径向应力。基于抛掷型岩爆机理和突变理论，提出了一种新的岩爆判据。同时，根据实际工程中的岩爆情况，给出了一种新的岩爆分类识别多因素指标。结果表明，应变岩爆与围岩塑性区半径和径向应力存在一定的相关性，可以利用开挖前的力学参数和应力分布进行估计，因此可以预测应变岩爆。通过大量岩爆实例划分岩爆区间，判据准确率达到80·36%，中强岩爆准确率达到83·33%。