Key Facts
• March 2025: JR Central installed new test embankments in Komaki, Aichi Prefecture.
• June 2025: Introduced “soil rainfall” as a new evaluation metric for operational regulations.
• 40% of the Tokaido Shinkansen tracks are built on embankments, higher than other lines.
• Heavy rain impacts embankment water levels, leading to frequent operational suspensions.
• Testing includes 200mm/hour rainfall simulation, unprecedented in Japan.
• Two embankment types tested: clay (resistant to infiltration but poor drainage) and sand (prone to infiltration but weak against heavy rain).
• New regulations allow localized thresholds based on terrain and historical rainfall data.
• Future goals: advanced simulation technology for embankment stability and further regulatory refinements.
Summary
JR Central is advancing measures to enhance the Tokaido Shinkansen’s resilience against heavy rain, addressing the increasing impact of extreme weather on operations. With 40% of its tracks on embankments, the line is particularly vulnerable to prolonged and intense rainfall. In March 2025, the company established new test embankments at its Komaki research facility to evaluate the effects of rain on different soil types. Using cutting-edge technology, including a 200mm/hour rainfall simulation system, JR Central aims to quantify water infiltration and improve embankment stability. Additionally, a new “soil rainfall” metric introduced in June 2025 enables more precise, localized operational regulations, potentially reducing suspension times. Future efforts will focus on advanced simulation tools and further regulatory adjustments to ensure safety and operational stability.
