桥梁桩基爆破近区地震波传播特性及应用研究

摘要

为研究桥梁桩基浅孔爆破地震波在爆源近区的传播特性及对邻近埋地天然气管道的影响，结合荣乌高速桥梁桩基爆破工程，现场布置与试验桩基边沿水平距离为L（2.2 m、3.2 m、5 m、9 m、15 m、21 m）的6个测点在不同的桩基深度H（12 m、14.5 m、15.5 m、18.2 m）下进行爆破试验。试验测试结果表明：随着水平距离的增大，水平径向和垂直方向的爆破振动速度呈现不同的变化趋势，且不同距离范围内，两者之间的大小关系也不相同；水平径向和垂直方向爆破振动速度随桩基深度的增加呈减小趋势，其中距离爆源越近，垂直方向振动速度减小趋势越明显；同等药量条件下，掏槽孔爆破振动远大于周边孔爆破振动。%To study the local propagation characteristics of seismic wave induced by the short-hole blasting of bridge pile foundation and the influence of blasting vibration on adjacent buried gas pipelines,according to blasting construction of bridge pile foundation located in Rongcheng-Wuhai highway,six measuring points with different hori-zontal distances(12 m、14. 5 m、15. 5 m、18. 2 m)to the edge of pile foundation were set in the blasting test under different depths of pile foundation(12m,14. 5m,15. 5m,18. 2 m). Tests showed that with the increase of horizontal distance,the blasting vibration velocity in vertical and horizontal radial direction revealed different trends;and the size relations between them were also different in different distances;the blasting vibration in both velocity horizontal radial and vertical direction decreased with the increase of pile foundation depth,and the closer to the blasting source,the more obvious the decreasing trend of the vertical vibration velocity would be;under the same condition, the vibration induced by cut-hole blasting was larger than that from peripheral hole blasting.