چكيده به لاتين
Measuring the characteristics of a rail track is an important step in the procedure of the maintenance and operational schedules for it. On the other side, the dynamics of rail vehicle and the related parameters such as acceleration and forces on the vehicle and passengers, all are dependent to quality of rail track characteristics.
Mainly, measuring the above mentioned characteristics is performed by manual and automated (rail track measuring cars) ways. Each of these ways have their pros and cons which depending on the current demand will be used.
In this research, measurement of rail track characteristics with measuring cars have been investigated and the effect of a few parameters on the quality of measurement is illustrated.
For this purpose, a measuring car developed by Plasser & Theurer named EM 120, have been modeled in the Universal Mechanism (UM) software and some simulations have been performed by it.
The research has shown that how the the measurements by a measuring car can be changed under different conditions and a sensitivity analysis of four parameters including stiffness of first suspension system, second suspension system, speed and ratio of wavelength on measuring chord length, on the recorded results by measuring car is performed. Also, it has been observed that measuring results of vertical irregularities are more affected by the mentioned ratio rather than horizontal irregularities.
Following to understanding of the importance of data acquired by mid-chord offset (MCO) method for measurement, a method was developed to post process measured data by MCO by filtering them through a specific equation which resulted to a very satisfying coincidence of corrected data and real track irregularities.
