Dynamic Behavior Analysis of a HighRise Traction System with Tensioned Pulley Acting on Compensating Rope In this paper, dynamic characteristics of the symmetrical traction system with tensioned pulley acting on compensating rope is theoretically investigated. Due to the excitations from drum, the traction system will occur longitudinal and transverse vibration. In order to explore the differences between traditional traction system and tensioned traction system with different tensioned methods and seek the optimal method of vibration suppression, the damping cylinder and terminal tension acting on compensating rope between tensioned pulley and ground are placed. Caused by the change of the ropexe2x80x99s property, the system will produce different dynamic responses. Here, the differentialalgebraic equations (DAEs) are derived using Hamilton principle. The transverse and longitudinal nonlinear coupling of ropes are considered. The generalized   xcexb1    method is selected to solve the DAEs. Based on the response characteristics of the system, the timefrequency characteristics with different terminal damping are obtained by CWT (continuous wavelet transform) and FFT (fast Fourier transform). From results, it can be seen that tensioned pulley plays an important role in suppressing transverse and longitudinal vibration of the symmetrical traction system compared with traditional traction system, especially by adding damping cylinder. The amplitude of system decreases exponentially with the increase of the terminal damping acting on tensioned pulley. Different running speeds of tensioned traction system are discussed. The results can inform the development of relevant mitigating strategies to minimize the effects of excessive vibrations.

Dynamic Responses of a Metro TrainBridge System under TrainBraking: Field Measurements and Data Analysis This paper focuses on the dynamic responses of a metro trainxe2x80x93bridge system under trainbraking. Experiments were performed on the elevated Metro Line 21 of Guangzhou (China). A continuous, threespan, rigidframe bridge (42 m  65 m  42 m) and a standard Btype metro train were selected. The acceleration signals were measured at the centerpoints of the main span and one sidespan, and the acceleration signals of the car body and the bogie frame were measured simultaneously. The trainxe2x80x93bridge systemxe2x80x99s vibration characteristics and any correlations with time and frequency were investigated. The Choixe2x80x93Williams distribution method and wavelet coherence were introduced to analyze the obtained acceleration signals of the metro trainxe2x80x93bridge system. The results showed that the Choixe2x80x93Williams distribution provided a more explicit understanding of the timexe2x80x93frequency domain. The correlations between different parts of the bridge and the trainxe2x80x93bridge system under braking conditions were revealed. The present study provides a series of measured dynamic responses of the metro trainxe2x80x93bridge system under trainbraking, which could be used as a reference in further investigations.