WIM data analysis for the fatigue lifetime evaluation of standard steel truss bridge elements

Bridge in Indonesia is designed using bridge loading standard SNI 1725:2016. Bridge is an infrastructure that withstands dynamic and repetitive loading. Vehicle load in this regulation are idealization of actual vehicle load. Weigh in motion (WIM) technology allow the measurement of vehicle load when vehicles moving, which is the actual load of traffic received by road and bridge. The effect of this loading on the bridge element, especially steel girder on Steel Truss Bridge type, there is repetitive occurrence of stress and relaxation due to vehicle loading in service life that can make the bridge failed due to fatigue. The purpose of this research is to evaluate the fatigue lifetime of steel truss bridge elements due to projection of accumulated vehicle load from WIM data. The bridge that will be evaluate on this research is 60 meters span steel truss bridge using WIM data of the Kaligawe Bridge, Semarang. This analysis was conducted by using stress range-number of cycles from structural analysis of accumulated WIM vehicular load, and compared to nominal fatigue resistances using stress range cycles-number curve (S-N curve). Evaluation method of fatigue with S-N curve method are specified in SNI and AASHTO. Evaluation results indicated that the fatigue limit of 50 year lifetime services on S-N curve which has not been surpassed and projected, the fatigue lifetime of the bridge would be on the 54^th.