Jonas W. Ringsberg

Bio: Jonas W. Ringsberg is an academic researcher from Chalmers University of Technology. The author has contributed to research in topics: Mooring & Vibration fatigue. The author has an hindex of 25, co-authored 167 publications receiving 2283 citations.

On propagation of short rolling contact fatigue cracks

Abstract: Recent accidents involving railway rails have aroused demand for improved and more efficient rail maintenance strategies to reduce the risk of unexpected rail fracture. Numerical tools can aid in generating maintenance strategies: this investigation deals with the numerical modelling and analysis of short crack growth in rails. Factors that influence the fatigue propagation of short surface-breaking cracks (head checks) in rails are assessed. A proposed numerical procedure incorporates finite element (FE) calculations to predict short crack growth conditions for rolling contact fatigue (RCF) loading. A parameterised FE model for the rolling-sliding contact of a cylinder on a semi-infinite half space, with a short surface breaking crack, presented here, is used in linear-elastic and elastic-plastic FE calculations of short crack propagation, together with fracture mechanics theory. The crack length and orientation, crack face friction, and coefficient of surface friction near the contact load are varied. The FE model is verified for five examples in the literature. Comparison of results from linear-elastic and elastic-plastic FE calculations, shows that the former cannot describe short RCF crack behaviour properly, in particular 0.1-0.2 mm long (head check) cracks with a shallow angle; elastic-plastic analysis is required instead.

State-of-the-art technologies, measures, and potential for reducing GHG emissions from shipping – A review

Abstract: © 2017 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

A Review of Rolling Contact Fatigue

Abstract: Ball and rolling element bearings are perhaps the most widely used components in industrial machinery. They are used to support load and allow relative motion inherent in the mechanism to take place. Subsurface originated spalling has been recognized as one of the main modes of failure for rolling contact fatigue (RCF) of bearings. In the past few decades a significant number of investigators have attempted to determine the physical mechanisms involved in rolling contact fatigue of bearings and proposed models to predict their fatigue lives. In this paper, some of the most widely used RCF models are reviewed and discussed, and their limitations are addressed. The paper also presents the modeling approaches recently proposed by the authors to develop life models and better understanding of the RCF.

Rail defects: an overview

Abstract: For about 150 years, the steel rail has been at the very heart of the world's railway systems. The rail works in a harsh environment and, as part of the track structure, it has little redundancy; thus, its failure may lead to catastrophic derailment of vehicles, the consequences of which can include death, injury, costs and loss of public confidence. These can have devastating and long-lasting effects on the industry. Despite the advances being made in railway permanent way engineering, inspection and rail-making technology, continually increasing service demands have resulted in rail failure continuing to be a substantial economic burden and a threat to the safe operation of virtually every railway in the world. This paper presents an overview of rail defects and their consequences from the earliest days of railways to the present day.