Maintenance strategy analysis for mud pumping defects in slab tracks based on track geometry data

Abstract

Mud pumping in slab tracks poses a significant threat to the structural integrity and operational safety of high-speed railways (HSRs). This study investigates the distribution characteristics and degradation mechanisms of mud pumping defects along a 301 km HSR line in eastern China. Based on multi-year inspection and maintenance data, a novel maintenance decision-making index (M-Index) is proposed to quantitatively assess track geometry degradation associated with mud pumping. Four typical defect scenarios (H1–H4) are defined based on the number of affected slabs and field observations. The M-Index is used to classify track segments into three management levels, corresponding to different stages of defect evolution and maintenance urgency. Degradation rates of track segments are calculated using linear fitting of the M-Index over grouting cycles, and percentile thresholds (70%, 80%, 90%) are introduced to guide condition classification. The study further proposes a data-driven maintenance strategy that incorporates track inspection data, M-Index evaluation, degradation rate analysis, and defect history logging. The results demonstrate that the proposed method enables accurate identification of deteriorating segments and supports timely and cost-effective maintenance planning.