地应力影响下岩石爆破损伤模型及其数值试验

发布时间：2018-06-17 04:20

本文选题：岩石爆破损伤 + 爆破应力波　；参考：《东北大学》2014年博士论文

【摘要】：在采矿工程、地下交通工程和水利水电工程等岩体开挖工程中,爆破法仍是一种主要的破岩方法。实施岩石爆破时,一方面要使开挖部分的岩石达到高效的破碎,另一方面又要尽可能减少爆破对边界以外围岩的损伤或破坏,有效地保护爆后保留岩石的稳定性。在地下深部岩石工程爆破中,地应力对于爆破过程也有着非常重要的影响。因此,建立岩石爆破损伤模型,对不同地应力条件下岩石爆破损伤过程进行研究,对于认识爆破机理和提高爆破效率,并同时保持既有岩体的稳定性,具有重要的理论与工程意义。本文开展的研究工作包括：(1)在考虑岩石介质非均匀性的基础上,把爆破损伤视为爆破应力波和爆生气体压力共同作用的结果,同时考虑初始应力场的静态作用,基于损伤力学理论建立岩石爆破的力学模型,并通过COMSOL Multiphysics软件环境下的Matlab有限元编程,实现所建模型的数值求解,研发岩石爆破损伤的数值模拟工具。(2)基于该爆破损伤模型,针对不同地应力条件下单孔爆破、双孔爆破过程开展数值试验,研究不同侧压力系数和埋深对裂纹萌生-扩展-贯通过程的影响,探讨初始应力场最大主应力方向对爆生裂纹扩展的导向作用。(3)针对不同地应力条件下含节理岩体爆破过程开展数值试验,研究地应力条件和节理角度对爆生裂纹萌生-扩展-贯通过程的影响机理,特别是节理角度对爆生裂纹扩展方向的导向作用。(4)对不同地应力条件下切缝药包爆破过程进行数值试验,研究切缝对爆生裂纹的定向控制作用,探讨侧压力系数、切缝角度、切缝厚度等因素对切缝药包定向控制爆破效果的影响机理。(5)针对边坡开挖预裂爆破工程开展相关数值试验,探讨不同的装药参数、起爆顺序、布孔方式对预裂和光面爆破效果的影响,为边坡开挖爆破设计提供理论依据。
[Abstract]:In mining engineering, underground traffic engineering, water conservancy and hydropower engineering, blasting is still one of the main rock breaking methods. In carrying out rock blasting, on the one hand, it is necessary to make the rock in excavated part break up efficiently, on the other hand, the damage or damage to surrounding rock beyond the boundary must be minimized as much as possible, and the stability of rock should be effectively protected after blasting. In deep underground rock engineering blasting, ground stress also plays an important role in blasting process. Therefore, the damage model of rock blasting is established, and the damage process of rock blasting under different ground stress conditions is studied, which is helpful to understand the blasting mechanism and improve the blasting efficiency, and at the same time to maintain the stability of the existing rock mass. It has important theoretical and engineering significance. The research work carried out in this paper includes: (1) considering the inhomogeneity of rock medium, blasting damage is regarded as the result of the combined action of blasting stress wave and explosion gas pressure, and the static action of initial stress field is considered at the same time. Based on the damage mechanics theory, the mechanical model of rock blasting is established, and the numerical solution of the model is realized by Matlab finite element programming under the environment of COMSOL Multiphysics, and the numerical simulation tool of rock blasting damage is developed. The effects of different lateral pressure coefficients and buried depth on the process of crack initiation, propagation and penetration are studied by numerical experiments on single hole blasting and double hole blasting under different geostress conditions. This paper discusses the guiding effect of maximum principal stress direction of initial stress field on explosion crack propagation. (3) numerical experiments are carried out for blasting process of jointed rock mass under different ground stress conditions. The influence mechanism of stress condition and joint angle on the process of initiation, propagation and transfixion of explosive crack is studied. Especially, the guiding effect of joint angle on the direction of explosion crack propagation. (4) the numerical test of explosive charge blasting process under different ground stress conditions is carried out, the directional control effect of cutting joint on explosive crack is studied, and the lateral pressure coefficient and cutting joint angle are discussed. The influence mechanism of cutting joint thickness and other factors on the effect of directional controlled blasting of cutting seam charge. (5) to carry out relevant numerical tests for slope excavation pre-splitting blasting engineering, and to discuss different charging parameters and initiation sequence. The influence of hole layout on the effect of pre-splitting and smooth blasting provides theoretical basis for the blasting design of slope excavation.
【学位授予单位】：东北大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TU45

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