Core Viewpoint - The Sichuan-Guizhou Railway and the Chongqing-Huaihua Railway have officially commenced their 2025 concentrated maintenance, aimed at enhancing the safety and quality of railway operations in Southwest China [1][3][4]. Group 1: Project Overview - The concentrated maintenance for the Sichuan-Guizhou Railway is set to last for 33 days, involving tasks such as rail replacement, major cleaning and screening, line tamping, mechanized sleeper replacement, and switch replacement to eliminate equipment defects [3][4]. - The Sichuan-Guizhou Railway, completed in 1965, serves as a crucial railway corridor in the Southwest region [3]. - The Chongqing-Huaihua Railway is a key national Class I double-track electrified railway connecting Chongqing with Huaihua City in Hunan Province, playing a vital role in linking the Yangtze River Economic Belt with the new land-sea corridor in the West [3][4]. Group 2: Maintenance Objectives - The concentrated maintenance aims to address fatigue damage caused by high-frequency loads on the railway tracks due to the increasing operation of passenger and freight trains [4]. - The maintenance activities are expected to significantly enhance the safety and stability of the railway equipment, thereby providing stronger transportation support for the high-quality economic and social development in the Southwest region [4].