Numerical Analysis on the Behavior of Prestressed Concrete Sleeper Under Different Support Conditions
| dc.contributor.advisor | Esayas, Gebreyouhannes (PhD) | |
| dc.contributor.author | Haftom, Gebremicael | |
| dc.date.accessioned | 2019-06-25T04:40:51Z | |
| dc.date.accessioned | 2023-11-04T15:16:58Z | |
| dc.date.available | 2019-06-25T04:40:51Z | |
| dc.date.available | 2023-11-04T15:16:58Z | |
| dc.date.issued | 2016-04-01 | |
| dc.description.abstract | Railway sleepers have important roles in the complex railway system. Throughout the international railway community, many methods have been developed to design and analyze the concrete sleepers. Specifically, this paper focuses on how changes in support condition affect the internal behavior of the sleeper. Due to different loading condition, poor maintenance or bad quality of ballast, a random load distribution along the sleeper-ballast interface may occur. A sleeper design, and also the track system design, which do not consider the random load distribution, could influence the performance of the sleeper and even damage the whole railway system. Thus, a numerical analysis for a pre-stressed concrete mono-block railway sleeper is carried out using finite element method. The internal behavior of a single sleeper subjected to a varying sleeper-ballast interaction is studied and, a linear-elastic sleeper analysis model was developed. This model was used to perform a study to determine the sensitivity of the sleeper to changes in ballast reaction along the sleeper. Four different possible scenarios of support conditions for a sleeper with varying contact length are discussed in numerical analysis. Results of vertical displacement and flexural stress of both rail seat and at mid-section of sleeper are presented. According to the simulations conducted in this study, the bending moments due to the applied rail seat load at the sleeper rail seat / center can be exceeded from design bending moments under small variation in distribution of the ballast reaction. Besides very soft support underneath the rail seat and large variation of ballast stiffness along the length of sleeper might cause severe cracking problems especially at the top surface in the middle of the sleeper. The worst support condition is also identified. Moreover, the results of this study were compared to existing design recommendations (Australian Standard AS 1085.14) to find allowable levels of ballast reaction that can occur beneath the sleeper before failure is expected. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/18583 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Prestressed concrete sleeper | en_US |
| dc.subject | varying support condition, sleeper-ballast interaction | en_US |
| dc.subject | rail seat and center bending stress | en_US |
| dc.subject | finite element modeling | en_US |
| dc.title | Numerical Analysis on the Behavior of Prestressed Concrete Sleeper Under Different Support Conditions | en_US |
| dc.type | Thesis | en_US |