The instability of railway tracks including mud pumping, ballast degradation, and differential settlement on weak subgrade soils occurs due to cyclic stress from heavy haul trains. Although geotextiles are currently being used as a separator in railway and highway embankments, their ability to prevent the migration of fine particles and reduce cyclic pore pressure has to be investigated under adverse hydraulic conditions to prevent substructure failures. This study primarily focuses on using geosynthetics to mitigate the migration of fine particles and the accumulation of excess pore pressure (EPP) due to mud pumping (subgrade fluidisation) using dynamic filtration apparatus. The role that geosynthetics play in controlling and preventing mud pumping is analysed by assessing the development of EPP, the change in particle size distribution and the water content of subgrade soil. Using 3 types of geotextiles, the potential for fluidisation is assessed by analysing the time-dependent excess pore pressure gradient (EPPG) inside the subgrade. The experimental results are then used to evaluate the performance of selected geotextiles under heavy haul loading.

由于重载列车的循环应力，铁路轨道的不稳定性包括泥浆泵送、道碴退化和弱路基土壤上的差异沉降。尽管土工布目前被用作铁路和公路路堤的隔板，但必须在不利的水力条件下研究其防止细颗粒迁移和降低循环孔隙压力的能力，以防止下部结构失效。这项研究主要集中在使用土工合成材料来减轻细颗粒的迁移和由于使用动态过滤装置泵送泥浆（路基流化）引起的超孔隙压力 (EPP) 的积累。通过评估EPP的发展，分析了土工合成材料在控制和防止泥浆泵送方面的作用，路基土粒度分布和含水量的变化。使用 3 种土工织物，通过分析路基内随时间变化的超孔隙水压力梯度 (EPPG) 来评估流化潜力。然后将实验结果用于评估所选土工织物在重载下的性能。