冲击作用下振动在地表传播规律的现场试验研究

Field-test Research on Vibration Propagation Rules on the Earth′s Surface under Impact

为研究巷道冲击地压产生的振动在地面上的传播规律,采取相似模拟试验研究,对朝关1号桥6#、8#桩基冲击施工现场进行试验,分析不同冲击能量在距冲击点不同距离、不同深度下冲击地层引起的振动在地面的衰减规律及对地表建筑的破坏形式。相似试验研究表明:不同冲击能量下峰值振速或主频随深度、距离变化的规律相似;峰值振速随深度增加先增后减,随距离增加呈指数衰减,非均质性使局部突变;主频随深度增加呈多峰结构,随距离增加局部波动,整体呈衰减趋势;对地表建筑的破坏形式主要是垂向压缩松动和径向挤压振荡。

In order to research the propagation rules of vibrations caused by rock burst in the rock roadway on the ground, the similar simulation experimental research was put forward, and field tests were carried out on vibratory construction of 6# and 8# pile foundation of No.1 bridge of Chaoguan. The attenuation laws of vibration caused by different impact energy were analyzed under different vibration distances and depths, and their damage forms to surface buildings were also studied. The similar experimental results were concluded as follows. Firstly, the peak vibration velocity or the fundamental frequency changing with depth and distance was similar under different impact energies. Secondly, the peak vibration velocity increased first and then de- creased with the increase of the hole depth, and exponentially decayed with the increase of distance. Heterogeneity resulted in local mutations. Thirdly, the main frequency increased with the depth and presented a multi-peak structure. With the increase of distance, the main frequency had local fluctuation and an overall trend of decay. Finally, the damage to the surface buildings mainly showed the forms of vertical compression loosening and radial crushing vibration.