【摘要】 将时变结构力学理论应用于岩爆发生机制的研究,以一个新的角度对岩爆动力源进行分析。地下洞室的围岩存在具有承载能力的自稳结构,首次提出了"自稳时变结构"的概念,定性地分析了临近开挖洞室的围岩自稳时变结构的特点。应用质点系动量定理,分析了围岩自稳时变结构的动力学响应。围岩自稳时变结构的质量随时间发生变化时,系统会出现负阻尼的情况,会形成动力不稳定系统而诱发岩爆。建立了围岩自稳时变结构诱发岩爆的力学模型,由力学模型可得出岩爆发生的两个条件:①围岩承受的切向应力σθ应使岩石产生扩容;②围岩自稳时变结构的质量减少。研究表明:岩爆的发生机制可通过围岩自稳时变结构理论得到很好的解释。更多还原

【Abstract】 The time-varying structure theory is applied to the researches on the mechanism of rockburst, the energy source of which is analyzed from a new angle. There are self-sustaining bearing structures in the surrounding rock of underground cavern. Furthermore, the concept of self-sustaining time-varying structure is put forward firstly, and the characteristics of the self-sustaining time-varying structures near the underground cavern are analyzed qualitatively. Applying the particle system momentum theorem, the dynamic response of the self-sustaining time-varying structures is calculated. The results indicate that the change of structural mass with time can supply negative damping which can cause dynamic instability and thus induce rockburst. A mechanical model is established to explain how the self-sustaining time-varying structures induce rockburst, if satisfying the two conditions: one is rock dilatancy under tangential stress σθ in the surrounding rock, the other is mass decrease of the self-sustaining time-varying structures. The researches indicate that the mechanism of the rockburst happening in underground engineering can be interpreted well by the time-varying structure theory.更多还原