Miwa M.,Track Geometry and Maintenance Laboratory |
Mizuno M.,Ex Track Geometry and Maintenance Laboratory
Quarterly Report of RTRI (Railway Technical Research Institute) | Year: 2014
Railway track irregularities need to be kept at a satisfactory level through appropriate maintenance work by using MTTs (Multiple Tie Tamper). We have developed an optimal track maintenance scheduling model taking train derailment accident risk into consideration. Firstly, we analyze derailment accident data in order to build a model for estimating the number of casualties when a train derailment accident occurs. Next, by applying the result, we develop an optimal track maintenance scheduling model in order to minimize the track irregularities and mitigate the train derailment accident risk. Finally, we apply our model to decision making for yearly tamping schedule, then try to show the optimal tamping schedule obtained by the model.
Shimizu A.,Track Geometry and Maintenance Laboratory |
Iida T.,Vehicle Dynamics Laboratory
Quarterly Report of RTRI (Railway Technical Research Institute) | Year: 2015
To evaluate running stability, equivalent conicity was computed by considering the combination of a new rail profile and arc wheel profile (for Shinkansen). The new rail profile was obtained by applying the radius of curvature of the top surface of a JIS 50kgN rail, 300 mm. The computation results when using the new rail showed small equivalent conicity and high running stability regardless of the degree of wear of the wheel. Furthermore, results from vehicle dynamics simulations showed that the new rail was endowed with running characteristics equivalent to those of JIS 60kg rail, and no evidence was found of any significant influence on running safety.
Hayama K.,Safety Analysis Laboratory |
Miyachi Y.,Safety Analysis Laboratory |
Nakamura R.,Safety Analysis Laboratory |
Kimura H.,Track Geometry and Maintenance Laboratory
Quarterly Report of RTRI (Railway Technical Research Institute) (Japan) | Year: 2011
In order to identify effective measures while confronted with limited time and budgets, priorities must be set according to the purpose and effect of a measure. The authors developed a "Human Error Risk management method". This is a method for evaluation which considers "the level of influence of the error-inducing factor" on a risk value evaluated by the combination of "possibility of being of an error" and "worst accident probable to occur due to the error". Consequently, a method for management of human error prevention is presented, which can be adopted by a rail track maintenance office. This paper introduces an example of its application to track maintenance.
Tanaka H.,Track Geometry and Maintenance Laboratory |
Shimizu A.,Track Geometry and Maintenance Laboratory
Quarterly Report of RTRI (Railway Technical Research Institute) | Year: 2016
Rail corrugation not only generates noise and vibrations but also causes track irregularity and deterioration of track material. It is therefore necessary to manage rail corrugation appropriately. Rail surface roughness due to rail corrugation is managed either through visual inspection or with a simple device. As such, this paper describes the development of a portable "Trolley for the Continuous Measurement of Rail Surface Roughness," designed to gather insight into the mechanisms leading to rail corrugation and developing measures to manage it efficiently. This trolley adopts the asymmetrical chord offset method for measuring the rail surface roughness continuously. A software was also built for controlling this trolley and. processing the measured, data. This paper presents the details of this development and describes some cases where the trolley could, be used. © 2016, Ken-yusha Inc. All rights reserved.
Tsubokawa Y.,Track Geometry and Maintenance Laboratory |
Yazawa E.,Track Geometry and Maintenance Laboratory |
Ogiso K.,Track Geometry and Maintenance Laboratory |
Nanmoku T.,Track Geometry and Maintenance Laboratory
Quarterly Report of RTRI (Railway Technical Research Institute) | Year: 2012
A prototype track measuring device was developed adopting the inertial mid-chord offset method, which can be mounted on commercial railway vehicles. The device was installed on a track inspection car which was then tested to evaluate its practical measuring accuracy and durability over the long term. Initial results showed that the accuracy of the device was lower when used at low speed. A method was therefore sought to compensate accuracy at low speed. This paper describes the outline of the developed car body mounted device, the results of running tests on commercial lines and the compensation method used to raise track measuring accuracy even at low speed.