[Anchor]
As extreme heatwaves continue, safety for railways and roads has been placed on high alert. This is because high temperatures can cause railway tracks to warp and concrete roads to expand, potentially leading to accidents. Authorities have launched an all-out response, deploying water sprays and stepping up surveillance.
Reporter Baegun has the details.
[Reporter]
High-speed railway lines during midday as a KTX train runs across.
Viewed through a thermal imaging camera, the tracks appear in a deep shade of red.
This is due to the heated rails and gravel.
On the ground, inspections are in full swing to check whether the gaps between the rails are consistent and if the fixings are secure.
As heatwaves persist, expanding forces build up within the steel rails. If fixing devices loosen during this time, a buckling phenomenon can occur where the rails warp sideways.
For this reason, automatic sprinkler systems are activated to spray water when rail temperatures rise to 48°C (118°F) or higher.
Such automatic sprinkler systems have been added to 142 locations this year alone, operating across 599 locations nationwide.
[Han Dong-yeol, Head of Osong Infrastructure Office, Korea Railroad Corporation: (Rail temperatures) drop by about 5°C to 10°C, and in areas with severe direct sunlight, water is sprayed for about 10 minutes up to 10 times a day.]
Even so, if rail temperatures continue to rise, trains slow down to 230 km/h or below when temperatures hit 55°C (131°F) or higher, and to 70 km/h or below at 60°C (140°F) or higher. Operations are suspended starting at 64°C (147°F).
Concrete paved on highways also expands when heatwaves persist for prolonged periods.
Therefore, gaps known as joints are created between the concrete to secure space.
If these gaps become blocked or narrow, leaving insufficient space for expansion, the concrete can push against each other and cause a buckling phenomenon where the road surface heaves upward.
In the summer of 2018, eight cases of pavement heaving occurred, even leading to accidents.
The Korea Expressway Corporation has installed stress-relief joints in vulnerable sections and mobilized dedicated vehicles to monitor roads.
[Ryu Sung-woo, Senior Researcher, Korea Expressway Corporation: (Stress-relief joints) provide an additional 100 mm width of space in sections where clearance has been lost. We are using equipment that can automatically inspect joint narrowing to detect risky sections in advance.]
In addition, authorities are contemplating countermeasures against increasingly extreme heatwaves every year, such as introducing construction methods from the design stage that suppress concrete expansion.
(Photo: Kang Si-woo | Video Editing: Shin Se-eun | Design: Choi Ha-nul)
※
Copying, redistribution, and unauthorized use in AI training are strictly prohibited.