武汉地铁区间隧道下穿建筑物爆破振动控制技术研究

为有效控制爆破振动对周围建筑物的扰动,研究爆破振动传播规律,结合现场环境和爆破器材,对武汉地铁纸坊大街站-小镇站区间隧道左线下穿建筑物区段进行爆破方案优化设计,并在建筑物地表设置监测点对爆破振动进行监测,然后通过10次监测所得数据分析爆破振动传播规律。结果表明:通过分台阶爆破、松动爆破、直孔掏槽、周边密集减振孔、空气间隔装药以及延时爆破等优化设计,将振动速度峰值控制在安全允许振速2.5 cm/s以下;中台阶、下台阶爆破时因上部存在自由面会有部分能量散失到空气中,导致工作面正上方测点振速减小,因此峰值振速随爆心距的增大先增大后减小。该工程技术可为其他复杂环境下的爆破工程提供参考和借鉴。

Research on blasting construction technology in subway tunnel beneath buildings in Wuhan

In order to control the harm of blasting vibration to surrounding buildings effectively and study the propagation law of blasting vibration, combining the site environment and blasting equipment,the blasting construction scheme is optimization designed for the section of buildings passing through the left line of Wuhan metro tunnel, and the blasting vibration is monitored by setting monitoring points on the surface of buildings, and then the propagation law of blasting vibration is analyzed based on the data obtained from 10 times of monitoring. The results show that the peak value of vibration velocity is controlled below the allowable vibration velocity 2.5 cm/s by bench blasting, loose blasting, straight hole cutting, dense shock absorption hole around, air interval charge and millisecond blasting. Some energy will be lost into the air due to the free surface in the upper part of the middle step and the lower step blasting, which will lead to the decreasing of peak vibration velocity with measurement point above the working face. So the peak vibration velocity increases at first and then decreases with the increase of explosion center distance. The construction technology provides a reference for blasting projects in other complex environments.