Why should there be a certain gap in the rail connection?
No, it's expansion and contractionMainly because the track is made of steel, it will heat up and contract cold.If you don't sew it, it will break in summer.But now the latest technology can be used in other ways to overcome the heat up cold contraction effect, as seamless.
But in the knowledge of the physics of middle school once learned, between the tracks and the track is to leave a little gap, because if you do not leave it in the summer, temperatures fell between the rail and rail mutual extrusion thermal expansion and contraction, causing damage to the road traffic safety hazards.
Now there are many high-speed railways have adopted the technology of seamless rail, they put the original welding gap between the rails, which no longer had left the gap between the tracks and the train tracks, running is stable, but also greatly reduces the noise between wheel and rail.
