Fatigue life of preloaded injection bolts in a bridge strengthening scenario – sensitivity analysis of fatigue life estimators. Issue 2 (1st September 2021)

• Record Type: Journal Article
• Authors: Pedrosa, Bruno; Rebelo, Carlos; Correia, José; Veljkovic, Milan; da Silva, Luís Simões
• Is Part Of: Ce/papers. Volume 4:Issue 2/4(2021)
• Page Start: 125
• Page End: 130
• Publication Date: 2021-09-01
• Subjects: Fatigue -- Injection Bolts -- Old Bridges -- Estimators -- Weibull; Civil engineering -- Periodicals; 624
• DOI: 10.1002/cepa.1271
• Languages: English
• ISSNs: 2509-7075

Abstract

Abstract: Old metallic bridges are prone to high levels of structural degradation due to their long service life, therefore, it is essential to study strengthening techniques. Implementation of injection bolts to replace riveted joints exposed to fatigue damages has been studied. The mechanical performance of injection bolts has been studied mainly based on quasi‐static or creep tests. The objective of this paper is comparison of fatigue resistance between bolted joints with preloaded injection bolts opposing bolted joints with preloaded high strength bolts. Specimens were defined aiming to reproduce as close as possible a strengthening scenario. Single and double lap joints were tested. The fatigue phenomenon has a stochastic nature and therefore robust models are necessary to estimate parameters of distribution functions. Therefore, different estimation methodologies were implemented to determine the parameters of Weibull distribution. The main goal was to define reliable S‐N design curves. Results showed that the use of preloaded injection bolts contribute to increase the fatigue life and to reduce the scatter, mainly for double lap joints. It is shown that S‐N curves of EN1993‐1‐9 do not represent the fatigue strength of structural details with old metallic materials.