强夯振动加速度的量测及现场试验研究
Measurement and Field Test Research on Vibration Acceleration of Dynamic Compaction

结合延安新区强夯加固地基工程，进行强夯振动加速度测试现场试验。选取填方区场地，结合地形设计监测方案，以测试强夯波沿水平方向和斜坡的传播规律。在选定试验段的某级填方场地上布置多组加速度传感器，运用多个8通道24位高速采集卡记录强夯振动加速度在平面和斜坡的传播和衰减过程，探讨强夯振动波沿水平面和斜坡的传播规律以及能级对振动加速度的影响。结果表明：径向和竖向加速度值均随与夯点距离的增大而减小；在与夯击点距离相同处，强夯振动波沿水平方向传播的径向和竖向加速度值要大于沿斜坡方向；随着能级的增大，强夯产生的夯击波增强，在与夯击点相同距离处产生的径向和竖向加速度均明显增大。
As a kind of foundation treatment method, dynamic compaction can quickly improve the bearing capacity and compressive modulus of foundations, with characteristics such as short duration, good effect, and low cost. However, the huge vibration waves caused by dynamic compaction tend to affect the stability of surrounding buildings and slopes. Therefore, it is of great theoretical and practical significance to study the propagation law of dynamic compaction vibration waves. In this study, combined with the monitoring scheme of a terrain design used in a dynamic compaction foundation project in the Yan'an New Area, we selected a site in the filling area in order to conduct field tests on the vibration acceleration of dynamic compaction. Based on these field tests, the propagation law of dynamic compaction vibration waves along the horizontal and the slope directions, respectively, were analyzed, and the effect of the energy level on the vibration acceleration was discussed. The results show that both the radial and vertical acceleration values of the vibration waves decrease with the increase of distance from the tamping point. At the same distance from the tamping point, the vertical and radial acceleration values along the horizontal direction were greater to those along the direction of the ramp. With the increase of energy level, the dynamic compaction waves were enhanced, and then both the radial and vertical accelerations at the same distance from the tamping point increased significantly.