Why are Tokyo subways so quiet, even though they have metal wheels?
An observation by
Frank X. Didik ---February, 2014
The reason is simple. In Tokyo, the tracks are completely smooth and the expansion joints merge slowly together, with two angular cuts. Many trains around the world use this same system. Further, the expansion joint can move further, thus potentially the tracks need to be serviced less frequently. On the other hand, here in NYC, we use the earliest methods by leaving a space between the rails, so in the summer time, when the the rail expands, a space is still present. Every wheel that rolls over the expansion joint makes a noise and vibration. Besides being noisy, this vibration ultimately wears the train (and rider) out quicker.
If you are a government official or a major contractor, please contact Frank Didik at inquiry [at] didik.com for a full report on how subways can be silenced and by doing so, reduce the damage to the subway car and tracks, caused by vibration, make the ride more comfortable and enjoyable, thus increasing ridership and ultimately save money, when vibration repairs are taken into consideration.