STUDY ON MRT BEARING

Abstract

Singapore Mass Rapid Transit (SMRT) has more than 12,000 bridge bearings installed along the bridge structure. The main function is to utilize the rubber pad in the bearings to reduce the impact caused by the movement of the trains on the structure. However, due to the deterioration of the rubber, the efficiency and effectiveness of the bearings deteriorate over the time. Since the MRT system is an important public transportation, it can not afford to replace the bearings after they have failed nor after accidents have occurred. Also to replace all the bearings will take about 5 years to accomplish. In this project, the vibrations of the bearings' displacement are measured and analyzed to evaluate the stiffness of the bearings. The stiffness increases over the time due to the aging process. By accelerating the aging process, it is possible to establish the value of the stiffness at which state the bearings fail to function. Hence, by monitoring the condition of the bearings, the lead time before failure occur can be estimated and replacement work can be scheduled. A mathematic model was also proposed to simulate the actual dynamic system to predict the response of the bearing.