复杂环境水下控制爆破工程影响效应测试分析

Tests and Analyses of the Effect of Underwater Controlled Blasting Projects in Complex Environments

摘要:

结合某沉管隧道沉管段基槽开挖工程,采用爆破动态效应的现场测试、理论分析等综合手段,探索水下爆破水中冲击波和爆破地震波动对邻近建筑物的动态效应特性。研究表明:(1)与地震波的峰值压力值相比,浅水条件下钻孔爆破水中冲击波压力值较小,传播速度也没有地震波快,特定情况下,在考量岸边堤岸及岸边建筑物的稳定性时可以忽略水冲击波的影响;(2)对于不同区域爆破施工来说,应根据其距离被保护对象的远近,选择各允许最大药量中的最小值作为最大爆破控制药量。研究成果对类似工程具有一定的借鉴意义。

Abstract:

As the effects of blasting vibrations from underwater construction blasting have increasingly gained attention, it is particularly important to conduct research to examine the behavior of underwater blasting vibrations. This paper combines the major foundation trench excavation projects of the immersed tube section in immersed tunnel engineering with indoor and outdoor testing of the bedrock, field tests of the dynamic blasting effects, theoretical analysis, and other comprehensive means to explore the effect of dynamic characteristics of underwater explosion shocks on adjacent land buildings and riverside embankments. The results show that(1) compared with the peak pressure value of a seismic wave, shock wave pressures of drilling blasting in water are small under the shallow water conditions and their propagation speeds are not faster than seismic waves, and therefore, when considering the stability of the embankment and shore buildings, the effects of water shock waves can be ignored under certain circumstances; and(2) concerning blasting constructions in different regions, the maximum blast should be the minimum of each of the allowed maximum doses based on the distances from the blasting point to the protected objects. The above results will provide an important reference for similar projects.