Unplanned Railway Maintenance of Highspeed Railway Systems Exposed to Extreme Weather Conditions

Abstract

Frequencies of climate extremes are increasingly noticeable in recent years. There are numerous sectors suffering from extreme weather conditions led by climate change. Railway transportation sector is one of those sectors negatively affected by extreme weather events such as extreme temperatures, storms, and floods. These extreme incidents mostly affect railway systems from both economic and social aspects. Due to impacts of climate extremes, substantial economic losses caused by service disruptions, delays, and even severe accidents may arise. In addition, railway infrastructures require comprehensive maintenance implementations due to damages caused by such extreme weather events. In this chapter, extreme weather events are analysed with respect to their effects on the railway maintenance activities and maintenance costs. A number of case studies from different countries subjecting extreme conditions are comprehensively assessed in order to develop climate resilience and adaptation policies for highspeed rail systems, aligned in United Nation’s Sustainable Development Goals (#11 Sustainable Cities and Communities and #13 Climate Action). Based on an EU-funded WEATHER, heavy rain/flood events have constituted the vast majority of the damage cost when compared to other analysed weather events. Damage cost to infrastructures is specifically in focus since significant maintenance and renewal are inevitable. The assessments show that average annual infrastructure damage cost is constituted to 33% of the total. In this chapter, extreme weather-related maintenance costs on the railway tracks in Turkey are focussed as a case study. The most common weather extremes affecting the railway lines in Turkey are selected for assessments including heavy rainfall/flood, landslide, heavy storm/snowstorm. Critical information regarding maintenance activities and comprehensive maintenance cost data are collected by means of expert interviews conducted with TCDD maintenance experts in Turkey. Consequently, a database of procured maintenance works in the past 10 years in Turkey can be established along with their total costs to TCDD. Preventative and corrective maintenance works associated with selected weather extremes are extracted from the database and used within the cost assessment. It is shown that maintenance activities related to heavy rainfalls/floods have constituted the majority as 52% of the total expense as $34.9 million followed by maintenance activities related to Heavy snow/snowstorm which have constituted 27% of the total expense as $17.7 million followed by maintenance activities related to landslides/earth movements which have constituted 21% of the total expense as $13.9 million. Note that $ refers to US dollar. The ratio of flood-induced maintenance and renewal cost to total maintenance and renewal cost arose in 2020 is obtained as 5.90%. The insights obtained from the case study provide a new reference in planning future preventative maintenance investments against potential flood occurrences in Turkey.