R&D on Rail Equipment for Faster Shinkansen Operating Speeds 

New tunnel hoods

When high-speed trains enter tunnels, compression waves in the air formed with the rapid increase in pressure are transmitted to the tunnel exit, sometimes creating an explosive sound at the exit. To restrain that sudden increase in pressure, a tunnel-shaped structure larger than the tunnel cross section is installed at the tunnel entrance. That structure is called a tunnel hood. Construction conditions are poor around most tunnel entrances and exits, causing installation expenses for hoods to tend to be high. For that reason, we are conducting development on technology for new structures that can be installed at lower cost than those with previous construction methods.

Shinkansen noise reduction devices (NIDES)

Noise near tracks becomes larger with increases in train travel speeds. JR East thus developed Shinkansen noise reduction devices (NIDES) to reduce wayside sound and is installing those on the top of existing soundproof walls. Those devices improve the noise reduction effect by using sound diffraction and interference phenomena in addition to sound blocking.