Pile network composite structures are used in the construction of high-speed railway subgrades. There have been few studies on their seismic dynamic response, however, which has restricted the accurate evaluation of their seismic performance. In this study, a series of shaking table tests on a pile network composite-reinforced soil high-speed railway subgrade were conducted. Particle image velocimetry was used to analyze the slope motion and sensor data to evaluate the overall dynamic response characteristics of the subgrade. Findings indicate that seismic activity causes subsidence throughout the subgrade, with deformations occurring in three distinct phases depending on the input seismic amplitude from 0.1 to 0.4 g (slow increasing), 0.4 to 0.6 g (faster increasing), and 0.6 to 1.0 g (rapidly increasing). The inclusion of geogrids aids in dissipating seismic energy, thereby reducing the peak acceleration amplification along the elevation. The increased dynamic soil pressure of the subgrade is mitigated by the geogrid reinforcement, which improves local stability. Moreover, the geogrid strain escalated with greater seismic wave amplitudes, resulting in the progressive expansion of the unstable zone from the slope towards the center of the subgrade as the elevation increased.

中文翻译：

---

桩网复合加筋土高速铁路路基地震动力行为的振动台研究


桩网复合结构用于高速铁路路基的建设。然而，关于其地震动力响应的研究很少，这限制了对其地震性能的准确评估。本研究对桩网复合土高速铁路路基进行了一系列振动台试验。采用粒子图像测速法分析边坡运动，采用传感器数据评价路基整体动力响应特性。研究结果表明，地震活动导致整个路基下沉，根据输入地震振幅的不同，变形分为三个不同的阶段，从 0.1 到 0.4 g（缓慢增加）、0.4 到 0.6 g（快速增加）和 0.6 到 1.0 g（快速增加）。土工格栅的加入有助于消散地震能量，从而减少沿高程的峰值加速度放大。土工格栅加固减轻了路基动态土压力的增加，从而提高了局部稳定性。此外，土工格栅应变随着地震波振幅的增加而增加，导致不稳定区从斜坡向路基中心逐渐扩展。