Progressive failure analysis of partially pre-stressed concrete railway sleepers

Abstract

Billions of sleepers are used on railways around the world today. As the importance of railways in the transportation sector is increasing, the demand for sleepers is also increasing. Although wooden and steel sleepers were used in rail systems in the past, today the most widely used sleeper type in the world is reinforced concrete sleepers. Among these reinforced concrete sleepers, pre-stressed sleepers are the most widely used, popular type of sleeper that can be produced in many countries. The two main production methods of pre-stressed sleepers are the ribbed reinforced system and the non-ribbed reinforced anchor plated system. In this study, B70 type pre-stressed concrete sleepers, have been investigated with the positive moment determination tests at the rail seat with progressive failure observations according to EN 13230-2:2016 standard. After tests, detailed cracking, failure, and fatigue analyzes under increasing test loads were performed with ANSYS® finite element analysis results for both types of pre-stressed sleepers. According to results, A-type sleepers have 50% more compression stress at the first crack formation load (Frr) than N-type sleepers and According to the first 0.05 mm permanent crack formation load (Fr0.05), it is seen that 25% higher stresses occur in A-type design than N-type design under Fr0.05 load. The results obtained through the analysis have been compared with the actual field measurement results, which have become more and more popular in the world in recent years. In this direction, various suggestions have been made for the development of concrete railway sleeper models.