Abstract

Fatigue verification of bridge structures requires information on the loads induced by heavy vehicles, which can be obtained from weigh in motion measurement (WIM) systems. The current fatigue load models applied in Europe are based on traffic load measurements in 1986. This paper evaluates the appropriateness of these models for today’s traffic by comparing their load effects with those of recent WIM databases, covering the years 2008 to 2018. A procedure is derived to determine the required size of the WIM database for a sound representation of the fatigue loads. The effects of traffic jams are evaluated and the required safety margins or partial factors are derived. As already concluded by others, it appears that the most frequently used fatigue load model is unable to represent the fatigue action effects of today’s European traffic. In addition, the paper demonstrates that the other fatigue load models are also inaccurate. A new fatigue load model is proposed that is easy in use and gives a significant improvement in accuracy compared to the existing models. The parameters in this model can easily be calibrated for other WIM databases.

Highlights

  • The European standard for actions on bridges, EN 1991-2 [1], pro­ vides fatigue traffic load models that should be used for the verification of fatigue of road bridges designed for Europe

  • Fatigue verification of bridge structures requires information on the loads induced by heavy vehicles, which can be obtained from weigh in motion measurement (WIM) systems

  • In order to determine the influence between such an assumption and the actual database, simulations are carried out with type A influence lines of Fig. 1(b) with the complete WIM database including the recorded intervehicle distances, and with the individual vehicles in that same database but with intervehicle distances increased so that one vehicle passes the bridge at a time

Read more

Summary

Introduction

The European standard for actions on bridges, EN 1991-2 [1], pro­ vides fatigue traffic load models that should be used for the verification of fatigue of road bridges designed for Europe. The fatigue load models (FLMs) in [1] are calibrated using traffic load measurements – i.e. measure­ ments of axle weights, vehicle composition and intervehicle distances of heavy vehicles – carried out in a motorway near Auxerre, France, in 1986, [2]. Because of its wide usage in practice, most researchers evaluated the accuracy of FLM3 by comparing its load effect with that of more recent WIM databases This model consists of two equal lorries that cross the influence line. The second part compares the WIM database with the traffic load models It pro­ poses a new method for calibrating a simple FLM, which includes loading on multiple lanes. The emphasis of this paper is not so much on the results, but instead it is on the methods used to calibrate a FLM and to derive the required database size

Description and representativeness of the WIM database
Accuracy and size of the WIM database
Evaluation of intervehicle distances
Accuracy of the fatigue load models in the Eurocode
Structural reliability and partial factors
New fatigue load model
Conclusions

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.