Study of a Space-Time Monitoring of High-Speed Railway Underline Structure Using Distributed Optical Vibration Sensing Technology

Figure 17

Vibration signal of the left track line after L00526 repair: (a) 1^st train; (b) 2^nd train; (c) 3^rd train; (d) 4^th train.

(a)

(b)

(c)

(d)