Evaluation of axle load increasing on a monumental masonry arch bridge based on field load testing

The importance and long serviceability period of a curved-in-plan masonry arch bridge, and the demand for allowable axle load increasing from 200 to 250 kN, convinced the authors to thoroughly assess the structure under the current standard loading conditions. Through the process of this research, the structure was modeled by taking advantage of the finite element method which accompanied by the model calibration using the obtained results of a predesigned field test, in which the precision of displacement measurement at the middle of main arch (with the height of 30 m from the riverbed) was 0.01 mm. By considering the dynamic impact factor resulted from the field test, the four plastic hinges mechanism and the serviceability limit state have been applied. Consequently, the ultimate adequacy factors of the bridge were resulted by the calibrated finite element model and the RING software. A reasonable agreement between the results was observed that assured the serviceability of the bridge for the current loading condition and even higher up to 250 kN.