Fatigue Analysis of the Railcar Wheelset Under Different Loading and Traction Condition: The Case of AALRTS
| dc.contributor.advisor | Celestin, Nkundineza (PhD) | |
| dc.contributor.author | Sileamlak, Ayenew | |
| dc.date.accessioned | 2021-11-23T08:34:43Z | |
| dc.date.accessioned | 2023-11-04T15:17:31Z | |
| dc.date.available | 2021-11-23T08:34:43Z | |
| dc.date.available | 2023-11-04T15:17:31Z | |
| dc.date.issued | 2019-08 | |
| dc.description.abstract | Railcar wheelset is a type of wheelset specially designed for use on rail tracks to transmit the sprung and unsprung weight of the train to the rail and to give traction. However, since they are subjected to cyclic axial, lateral and horizontal loads fatigue failures are common. In addition, a railway companies like Addis Ababa light rail train (AALRT) Transport passengers and goods in most cases face overloading beyond the loading capacity. On the other hand, the speed has a direct effect on the fatigue of wheelset. By fundamental mechanics for a train moving at constant power, increase in speed causes the decrease in axle twisting moment leading to a decrease in torsional stresses; but, this effect is only significant at relatively low and medium speeds. Also, according to Hirakawa & Kubota (2001), increase in speed causes an increase in axle bending stresses; but, this effect is only significant at very high speeds and the effect is nonexistent for speeds less than 60 km/hr. Therefore, the main objective of this paper is to perform stress and fatigue analysis of a wheelset under different loading and traction conditions on a straight railroad in case of AALRT. This research uses both primary and secondary data sources for analysis. The researcher employs different analytical and numerical approaches, to determine induced stresses and loads that act on the wheelset. We use different mechanics theories (static and dynamic) and FEA analysis was carried out by ANSYS 15.0 for different loading (39158.25 N, 51571.36 N & 57307.88 N) and traction condition ( . On the bases of this analysis the results show that the fatigue life improves by 57 % if the trains carry passengers only by seat and by 16% if AALRT limits the passenger number to 317 passengers/train instead of 420 passengers per train. Also, the results show that the increased average speed up to 40 km/hr. contributes to the increase of fatigue life and factor of safety of the axle caused by a combination of twisting and bending moments by 3.1 % and 4%, respectively. The results in this analysis provide a good start to be taken by an urban rail transit such as AALRT to determine optimum train loadings and travel speed range in combination of other detrimental factors that were out of scope of this research. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/28897 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | AALRT | en_US |
| dc.subject | wheelset | en_US |
| dc.subject | Fatigue failures | en_US |
| dc.subject | FEA analysis | en_US |
| dc.subject | Overloading | en_US |
| dc.subject | fatigue of railway axle | en_US |
| dc.title | Fatigue Analysis of the Railcar Wheelset Under Different Loading and Traction Condition: The Case of AALRTS | en_US |
| dc.type | Thesis | en_US |