隧道楔形分段掏槽爆破减震机理及试验研究

发布时间：2018-04-20 04:27

本文选题：隧道工程 + 楔形分段掏槽　；参考：《现代隧道技术》2017年04期

【摘要】：为合理解决邻近既有建(构)筑物隧道爆破开挖中降低爆破振动强度与确保施工效率之间的矛盾,基于隧道开挖时常用的楔形掏槽方式,文章优化提出了适用于中软岩隧道开挖的减震爆破技术——楔形分段毫秒延迟掏槽爆破技术。此技术借助掏槽炮孔内实行间隔分段装药结构及毫秒延迟起爆技术,确保掏槽腔体由外及内分次分层形成,以达到有效减震和获取良好爆破进尺的目的。文章在详细分析楔形分段掏槽爆破中岩体破碎和减震机理的基础上,基于微差爆破和应力波传播理论提出了影响楔形分段掏槽爆破减震和掏槽效果的掏槽深度比、段间装药分配比、炮孔倾角和段间延迟时间等关键技术参数的确定方法,并应用于指导开展现场隧道爆破试验的参数设计。现场爆破试验结果表明:楔形分段毫秒延迟掏槽爆破技术是一种既能有效降低爆破振动强度又能确保隧道施工速率的技术措施;与常规楔形掏槽爆破技术相比,此技术可将掏槽爆破产生的振动强度降低30%以上,并可获得良好的爆破进尺与效果。
[Abstract]:In order to reasonably solve the contradiction between reducing blasting vibration intensity and ensuring construction efficiency in blasting excavation of adjacent existing building (construction) tunnel, based on the wedge-shaped cutting method commonly used in tunnel excavation, In this paper, a new blasting technique, wedge-shaped segmented millisecond delayed cutting blasting, which is suitable for the excavation of middle soft rock tunnel, is put forward. With the help of the intersecting charge structure and millisecond delay initiation technology in the cutting hole, this technique ensures that the cut cavity is formed by the external and internal stratification, in order to effectively reduce the vibration and obtain a good blasting advance. On the basis of detailed analysis of the mechanism of rock mass breakage and vibration absorption in wedge sectioned cut blasting, based on the theory of millisecond blasting and stress wave propagation, the cutting depth ratio which affects the damping and cutting effect of wedge segmented cut blasting is put forward in this paper. The methods of determining the key technical parameters such as the ratio of charge distribution between sections, the angle of hole inclination and the delay time between sections are applied to guide the parameter design of the field tunnel blasting test. The results of field blasting test show that wedge-shaped segmented millisecond delay cutting blasting technology is a technical measure which can effectively reduce blasting vibration intensity and ensure tunnel construction rate, and is compared with conventional wedge cutting blasting technology. This technique can reduce the vibration intensity of cutting blasting by more than 30% and obtain good blasting scale and effect.
【作者单位】：遵义市新区开发投资有限责任公司;西南交通大学土木工程学院;中铁东方国际集团有限公司;
【基金】：乌鲁木齐市应用开发研究计划项目(Y131320008)
【分类号】：U455.6

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