Effect of Rail Surface Grinding on Service Life Extension of Railway Turnout Using Fatigue Analysis

Author(s):  
Sooho Chae ◽  
◽  
Taegyeong Jang ◽  
Sanghyun Choi
1989 ◽  
Vol 5 (02) ◽  
pp. 79-89
Author(s):  
Koichi Baba ◽  
Takao Wada ◽  
Soichi Kondo ◽  
M. S. O'Hare ◽  
James C. Schaff

Philadelphia Naval Shipyard's application of zone logic to ship overhaul is neither small nor isolated. PNSY started its implementation of zone logic in the late fall of 1986, targeting the Service Life Extension Program (SLEP) for USS Kitty Hawk (CV-63) as the initial application. The technical services of Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI), Japan were contracted to assist in this transition. This implementation on the Kitty Hawk is not a trial effort but involves about one third of the production man-days and covers over one half of the compartments on the ship. The actual SLEP production work on Kitty Hawk began in January 1988. Even though it is early in the three-year SLEP, zone logic already is proving its worth. This paper explains the zone logic methods and methodology applied at PNSY on Kitty Hawk. It also discusses the future of zone logic at PNSY and its continued application.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Aruz Petcherdchoo

This paper presents sensitivity of service life extension and CO2 emission due to silane (alkyltriethoxysilane) treatment on concrete structures under time-dependent chloride attack. The service life is predicted by the Crank–Nicolson-based finite difference approach for avoiding the complexity in solving Fick’s second law. The complexity occurs due to time-dependent chloride attack and nonconstant diffusion coefficient of concrete with silane treatment. At the application time of silane treatment, the cumulative CO2 emission is assessed. The effectiveness of silane treatment is defined as the ratio of the service life extension to the cumulative CO2 emission assessed within the corrosion-free service life. The service life extension is defined as the difference between corrosion-free service life of concrete structures without and with time-based application of silane treatment. From the study, the diffusion of chlorides in concrete with silane treatment is found to be retarded. In comparison, the strategy without deterioration of silanes during effective duration is more suitable for service life extension but less effective than that with deterioration. In the sensitivity analysis, there are up to eight parameters to be determined. The service life of concrete structures without silane treatment is most sensitive to the water-to-cement ratio and the threshold depth of concrete structures. Considering only five parameters in silane treatment strategies, the service life is most sensitive to the first application time of silane treatment. The cumulative CO2 emission is most sensitive to either the first application time of silane treatment or the amount of CO2 emission per application.


2017 ◽  
Vol 728 ◽  
pp. 384-389
Author(s):  
Aruz Petcherdchoo ◽  
Chotima Ongsopapong

This study presents assessment of the environmental impact in terms of the CO2 due to silane treatment for extending corrosion-free service life of concrete structures under chloride attack. To achieve this, there are two issues to be addressed; prediction of corrosion-free service life extension, and assessment of the amount of CO2 emission. In predicting the corrosion-free service life extension, the behaviors of chloride diffusion before and after time-based silane treatment are considered. Then, the cumulative CO2 due to silane treatment is accordingly calculated. The ratio of the corrosion-free service life extension to the cumulative CO2 is defined as the effectiveness of silane treatment, and used to compare different silane treatment strategies.


2019 ◽  
pp. 67-71 ◽  
Author(s):  
V. I. Bolobov ◽  
◽  
S. A. Chupin ◽  
V. S. Bochkov ◽  
I. I. Mishin ◽  
...  

Author(s):  
Ludmila Blazhko ◽  
Vladislav Zakharov ◽  
Yevgeniy Chernyayev ◽  
Yevgeniy Shekhtman

Objective: To reduce side wear of rail elements of side track backing-up rail. Methods: Comparative and computational methods were applied in the study. Results: It was detected that in order to extend the pointwork turnout curve service life, it is necessary to reduce the side impact on an outer rail by using rail pads of diverse elasticity. Practical importance: Application of rail pads of diverse elasticity under the outer and inner rails of a pointwork turnout curve makes it possible to increase the speed of rolling stock movement on the side direction of pointwork and increase the life of a pointwork turnout curve with fixed train speed.


2020 ◽  
Vol 10 (13) ◽  
pp. 4561
Author(s):  
Youn-Ju Jeong ◽  
Min-Su Park ◽  
Sung-Hoon Song ◽  
Jeongsoo Kim

In this paper, for the case of “service life extension” with the same capacity for wind turbines, a structural safety evaluation was carried out to determine whether to extend the service life of the aged foundation. As a result of this study, it was found that the aged foundation satisfies the structural safety of material strength, ultimate strength, fatigue life, and serviceability up to the present. Although the in-service period has been over 16 years, it has been shown that the material properties of concrete have exceeded the design strength, and no significant material deterioration has occurred. Also, structural safety could be evaluated more realistically based on actual concrete properties. In particular, it has been shown that it has a fatigue life of 40 years or more, so service life can be extended. It is expected that the methodology used in this paper will be useful not only for structural safety evaluation of the foundation in service, but also for decision-making for extending the service life. Furthermore, a more technical approach should be explored by many researchers in the future.


Author(s):  
Peter H. Møller

<p>A monitoring system for measuring the durability of concrete repairs has been developed and tested for 6 years as part of a pilot project for renovation of bridge piers. Beside testing traditional repair methods, the possible service life extension from cast-in sacrificial anodes was tested.<p>The system was focused on the zone between original concrete and repair material where corrosion often starts. It was seen that this zone for most of the repairs can be expected to reduce service life to <50years. But the monitoring system cannot determine the service life precisely, but precision is highly increased compared to other methods, e.g. surface based mapping of reinforcement potentials. The results furthermore indicated that cast-in anodes can increase the service life by 10- 20 years. By the new anode model, Galva Shield XP2, service life be might increased by 15-30 years.<p>It was found that corrosion risk at repairs has high areal- and time-based variations and to obtain an overview of the durability of the repairs several repairs must be monitored for a long time.


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