Crack Propagation Analysis and Its Life Prediction for Railroad Rails Using FEA
| dc.contributor.advisor | Daniel, Tilahun (PhD) | |
| dc.contributor.author | Abdurahman, Haji | |
| dc.date.accessioned | 2019-01-01T04:50:31Z | |
| dc.date.accessioned | 2023-11-04T15:16:47Z | |
| dc.date.available | 2019-01-01T04:50:31Z | |
| dc.date.available | 2023-11-04T15:16:47Z | |
| dc.date.issued | 2015-04 | |
| dc.description.abstract | Now a day the railway transport infrastructure in Ethiopia is the major issues in relation to the development of the country. To strengthen this infrastructure, related researches must be conducted at the beginning of the construction of the sector. This paper which mainly concerned about the analysis of crack propagation of rail due to vertical wheel load is done to predict the initiated crack growth rate under different load conditions. The objective of this research is to analyze propagation of initiated crack and determine its growth rate under different load conditions and to identify the maximum axle load used, which is basic to justify the way of crack propagation near to the contacting interface. A design axle load of 25ton (ERC) and 22.5tons and 20tons are assumed for the calculation of Stress Intensity factors. A wheel of S1002 profile and a UIC60 rail profile are modeled using CatiaV5R19 software. The models are assembled and imported to Ansys 15.0 release workbench and then to Ansys APDL to simulate wheel/rail contact. The material properties of rail steel are taken and a side crack model is made to simulate crack propagation of railroad rail taking only the vertical load from wheel. The cracked plate is assumed as it is taken from a cracked rail. Then, initiated cracks of different sizes are taken and tensile stress loads are applied on each crack length. The analysis is done taking into account the theories of Linear Elastic Fracture Mechanics. The analysis is based on numerical and analytical methods. For numerical methods, the analytical stress intensity factor KI is calculated using a formula given by (Ewalds and Wanhill, 1989). The analytical method uses Ansys KCALC (Displacement extrapolation method) based on the stress and strain plane conditions. Both results are compared with the numerical results. The tensile loads which take in to account the effects of the dynamic magnification of the vertical wheel load show higher SIF and the life cycle the cracks under these cases are shorter. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/15409 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | AAU | en_US |
| dc.subject | Crack Propagation | en_US |
| dc.subject | Crack Growth Rate | en_US |
| dc.subject | Linear Elastic Fracture Mechanics | en_US |
| dc.subject | WheelRail Contact Geometry | en_US |
| dc.title | Crack Propagation Analysis and Its Life Prediction for Railroad Rails Using FEA | en_US |
| dc.type | Thesis | en_US |