An easy instrument and a methodology for the monitoring and the diagnosis of a rail

Nowadays, there are no systematic methodologies for evaluating life assessment of the rail, and few systems provide the measures of vertical and lateral forces that train exchanges with the rail. These systems are quite expensive and require the substitution of a portion of the track. In the present paper is presented a simple transducer (MPQY) for measuring, at the same time, the vertical and lateral forces. The easy installation and use of this instrument are its main characteristics. It is sufficient to put it in a hole, made in the rail web in the concurrence of the drilling axis, and connect it to the transmitting station for measuring for each convoy the vertical and lateral forces induced by each wheel. It can be also used for analysing speed and mass of trains and the specific derailment ratio. In addition, by using a damage model, it is possible to estimate the residual life of a rail. In order to do this, a linear model of rolling contact fatigue damage is implemented and tested with same experimental acquisitions. Another application of this transducer can be identified in the variation of the mechanical behaviour of ballast. In fact, by using the information coming from the MPQY and comparing it with the flexural moment measurement, it is possible to evaluate the variation of ballast behaviour with respect to time and set new parameters for ballast maintenance and train safety.

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