桩井爆破振动在边坡的传播规律及预测分析

摘要

为研究桩井爆破地震波在邻近边坡传播规律,提高预测精度,对桩井爆破振动速度进行了现场测试.现场测试结果表明:(1)切向平均衰减速率最大,径向其次;(2)爆破地震波在边坡存在坡面效应,且其具有区域性和方向性,在台阶上部边缘以垂向振速放大为主,在台阶坡面以径向振速放大为主;(3)岩土介质性质变化对爆破振动速度影响较大.提出了利用桩井开挖深度H预测K、α值的桩井深度预测公式,对比萨道夫斯基公式、高程修正公式及该预测公式,该式预测精度最高,平均误差为18.4％.%To study the propagation of blast seismic wave caused by pile-well blasting on the slope nearby and to improve the prediction accuracy,the test of vibration is carried out in pile-well blasting.The field test results show that the average attenuation rate of tangential is the biggest and rate of the radial came second;the blast seismic wave produces slope effect,where,the amplification of vertical direction velocity is based on the upper edge of the step and radial direction is based on the slope surface;the change of rock media properties makes large effect on blasting vibration velocity.A new method is proposed to forecast the values of K and α by the pile-well excavation depth H,compared with Sadaovsk formula and altitude correction formulas,which improves prediction accuracy with average error 18.4％.