ANALYSIS OF RAIL WEAR AND PREDICTION OF SERVICE LIFE AT THE FATMAWATI CURVE OF MRT JAKARTA

Abstract

Urban mass transit systems, such as the Jakarta Mass Rapid Transit (MRT) support high mobility but face track maintenance challenges from rapid degradation. Rail wear is the gradual loss of material due to repeated wheel rail contact while the contributing factors include friction, forces, accumulated passing tonnage, environmental conditions, material quality, and lack of lubrication. The Fatmawati Curve, characterized by a sharp 180-meter radius, exhibits one of the highest wear rates along the MRT Jakarta line due to intense dynamic forces. This study comprehensively analyzes the rail wear rate and its contributing factors at this critical location, while predicting the remaining rail service life using Simple Linear Regression and the theoretical AREA (American Railway Engineering Association) method. Empirical data were obtained from precise measurements conducted by the Civil Permanent Way Maintenance (CPWM) team of PT MRT Jakarta from May 2024 to June 2025 on both the Up Track and Down Track. The analysis results indicate that horizontal wear is the dominant degradation mechanism on this curve, progressing significantly and exceeding 5 mm after 84 months of operation, while vertical wear remains minimal at below 1.5 mm. Based on the maximum wear limits stipulated by national regulations (Permenhub No. 32/2011), the Simple Linear Regression model estimates that the critical wear limit will be reached between 2029 for the Down Track and 2030 for the Up Track. In contrast, the AREA method provides a longer, theoretical service life estimation extending to 2035 because it primarily accounts for material fatigue limits rather than physical field wear. Because the linear regression projections more accurately reflect actual aggressive field conditions, proactive track maintenance interventions such as optimized track lubrication, geometric control, and scheduled rail replacement at the Fatmawati Curve are highly recommended prior to 2029 to prevent technical failures and ensure long-term operational safety.