Vibration Behavior and Reinforcement Effect Analysis of the Slab Track-Subgrade with Mud Pumping under Cyclic Dynamic Loading: Full-Scale Model Tests
Vibration Behavior and Reinforcement Effect Analysis of the Slab Track-Subgrade with Mud Pumping under Cyclic Dynamic Loading: Full-Scale Model Tests
复制标题
循环动载下泵泥板式轨道路基振动行为及加固效果分析：足尺模型试验
DOI：
10.1155/2018/3087254
复制
发表时间：
2018-01-01
影响因子：
1.6
通讯作者：
Guo, Huiqin
中科院分区：
文献类型：
--
作者：
Huang, Junjie;Su, Qian;Guo, Huiqin
路基基床翻浆会逐渐恶化板式轨道路基的使用性能，影响高速铁路的舒适性和安全性。建立了板式轨道-路基足尺模型，分析了模型在正常状态下、泵泥加固前后的振动特性，以及低粘度环氧树脂泵泥加固效果。研究结果表明，正常工况下，随着荷载循环次数的增加，模型的振动加速度、位移和沉降量逐渐趋于稳定。在饱和水的基床上层，第二阶段加载达到3.0 × 104次时，基床发生了翻浆现象，且随着加载次数的增加，翻浆的劣化程度逐渐加重。此外，模型在第二阶段2.0 × 106次循环荷载作用后，大量由水和细颗粒组成的浆液被挤出基床，造成混凝土基层与基床之间的接触损失，使混凝土基层的加速度和位移较正常工况下的模型异常增大，以及路基基床的累积沉降。采用低粘度环氧树脂对基床上层抽泥严重的模型进行加固处理。有效地控制了混凝土基础的异常加速度和位移，恢复了道床对板式轨道结构混凝土基础的支撑能力。
Mud pumping occurring in the subgrade bed can gradually deteriorate the performance of the slab track-subgrade, negatively affecting the comfort and safety of high-speed railway. In this paper, a full-scale model of the slab track-subgrade was established to analyze the vibration behavior of the model in normal condition and before and after mud pumping reinforced, as well as the reinforcement effect of mud pumping using low-viscosity epoxy resin. The research results show that the vibration acceleration and displacement and the settlement of the model in normal condition stabilize gradually with the increasing number of loading cycles. Under the upper layer of the subgrade bed saturated by water, mud pumping occurs in the subgrade bed as soon as the second loading stage reaches to 3.0 × 104 cycles, and the deterioration of mud pumping increases gradually with the increasing number of loading cycles. Moreover, a large volume of slurry composed of water and fine particles is squeezed out of the subgrade bed after the model is subjected to the second cyclic loading stage of 2.0 × 106 cycles, causing contact loss between the concrete base and the subgrade bed, which makes the acceleration and displacement of the concrete base increase abnormally compared with the model in normal condition, as well as the cumulative settlement of the subgrade bed. The model with significant mud pumping in the upper layer of the subgrade bed was reinforced by using low-viscosity epoxy resin. This effectively controlled the abnormal acceleration and displacement of the concrete base and restored the support capability of the subgrade bed for the concrete base of the slab track structure.