椭圆双极线性聚能水压爆破数值分析及应用

Numerical Analysis and Application of Elliptical Bipolar Linear Energy-gathering Hydraulic Control Blasting Based on SPH-FEM

研究目的:为减少爆破活动对隧道施工环境的影响,降低爆破过程中产生的粉尘浓度,同时增强对开挖区的爆破作用,经常会采用聚能水压控制爆破的爆破施工方式。为对椭圆双极线性聚能水压爆破荷载演化过程进行模拟和验证,本文依托金井铁路隧道现场工程试验和数值模拟的方法,分析聚能水压控制爆破作用机理及损伤演化过程。研究结论:(1)在椭圆双极线性聚能定向爆破作用下,炮孔附近的裂纹发展具有一定的趋向性,在增强聚能方向裂纹拓展的同时抑制了其他方向裂纹的发展;在炮孔中加入水介质,能够增强爆破效果;(2)对比三种聚能水压爆破结构形式,上部水压力聚能爆破结构造成的损伤主要集中于孔口附近,下部水压力聚能爆破结构对孔底产生的损伤较大,而两端水压力聚能爆破结构产生的损伤区域整体均匀,脱落下来的碎石破碎程度较高,且水介质能够中和爆破过程中产生的粉尘;(3)综上所述,将两端水压力聚能水压控制爆破结构应用于隧道施工建设能够取得最佳的爆破效果。

Research purposes:To reduce the influence of blasting activities on the tunnel environment,reducing the concentration of dust generated during blasting,while enhancing the blasting effect on the excavation area,the energy-gathering hydraulic blasting is often used.This paper simulates and verifies the gradual evolution process of the elliptical bipolar linear energy-gathering hydraulic blasting through numerical simulation and field engineering experiments in Jinjing railway tunnel,and analyzes the action mechanism and damage evolution process of energy-gathering hydraulic blasting.Research conclusions:(1) The development of cracks near the borehole has a certain tendency under the energy-gathering hydraulic blasting,enhancing the crack propagation in the energy gathering direction while restraining the development of cracks in other directions.It can enhance the blasting effect in the borehole by adding water.(2) By comparing hydraulic blasting three forms energy-gathering structure,the damage caused by the upper hydraulic energy-gathering blasting structure is mainly concentrated near the borehole,and the lower hydraulic energy-gathering blasting structure causes great damage to the hole bottom.And the damage area produced by the two-way hydraulic energy-gathering blasting structure is uniform,the falling stones have a higher degree of crushing,and the water medium can reconcile and neutralize the dust generated during the blasting process.(3) According to the above,the best blasting effect can be achieved by the construction of two-way hydraulic energy-gathering hydraulic control blasting of tunnel construction.