An examination of mixed fatigue-tensile surface crack growth in rails |
| |
Authors: | G Glinka Z Gmur Z ?widerski |
| |
Affiliation: | London Centre for Marine Technology, Department of Mechanical Engineering, University College London, Torrington Place, London WC 1E 7JE, England;Research Institute of the Polish State Railways, 04-275 Warsaw, ul. Chtopickiego 50, Poland |
| |
Abstract: | The fracture instability associated with alternating periods of fatigue and tensile growth of surface cracks was investigated in steel rails. Three different steels were tested. The instabilities commenced when the maximum stress intensity factor exceeded the fracture toughness and resulted in crack jump or total rail failure. The conditions for the establishment of fatigue-tensile crack jump and arrest are described. The load level, residual stresses, crack geometry and fracture toughness effects are analysed. The fatigue surface cracks were penetrated in both stress relieved and stress unrelieved rails. The effective stress intensity factors including the contribution of the applied load and residual stresses were calculated. For both the fatigue-tensile and tensile-fatigue transitions the stress intensity factors were almost the same with the value for the tensile-fatigue transition being slightly lower. Both calculated stress intensity factors were close to the fracture toughness . |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|