爆破振动下隧道初支混凝土振速衰减规律

Vibration velocity attenuation law of initial support concrete in tunnel under blasting vibration

为研究爆破振动作用下隧道初支混凝土喷层的振动响应与初支混凝土喷层爆破振动衰减规律,依托于成昆铁路峨眉至米易段扩能工程沈家坝1号隧道,通过现场试验获得爆破振动信号,使用小波变换方法对爆破振动信号进行时-频分析,得到了爆破振动信号的时频特征。依据萨道夫斯基经验公式对试验的振速数据进行线性回归分析,得到爆破振动衰减规律,并拟合出爆破动载作用下初支混凝土喷层振速与药量、爆心距之间的关系曲线,用于指导隧道的钻爆施工。

In order to study the vibration response of the primary sprayed concrete layer of the tunnel under the action of blasting vibration and the blasting vibration attenuation law of the primary sprayed concrete layer, relying on the Shenjiaba No. The blasting vibration signal is time-frequency analyzed by using the wavelet transform method, and the time-frequency characteristics of the blasting vibration signal are obtained. According to Sadovsky’s empirical formula, linear regression analysis was carried out on the vibration velocity data of the test, and the law of blasting vibration attenuation was obtained, and the relationship between the velocity of the primary shotcrete sprayed layer under the action of blasting dynamic load, the amount of charge, and the distance between blast centers was fitted. The curve is used to guide the drilling and blasting construction of the tunnel.