Response Surface-Based Finite Element Model Calibration of a One-Span Historical Masonry Bridge

Abstract

This study aims to investigate the dynamic behavior of a one-span historical masonry arch bridge. For thisreason, the masonry bridge with 15.5m in length and 4.75m in width was chosen and the modal parameterswere obtained by performing numerical analyses and experimental measurements. Operational ModalAnalysis technique is utilized for experimental study to determine modal parameters of the historicalmasonry bridge. Sensitive three-axial accelerometers were located on critical points on the bridge span andsignals originated by accelerometers were collected to quantify the vibratory response of the historical bridge.The Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification method areemployed to identify the natural frequencies, mode shapes, and damping ratios experimentally. The 3D finiteelement modeling of the historical masonry bridge was created and the natural frequencies and mode shapesof the bridge were determined numerically. Experimental results were compared with those of the finiteelement analysis of the bridge. It can be noticed significant differences when comparing the results of theexperimental and numerical with the initial conditions. Therefore, the finite element model is calibrated byusing the response surface method according to the experimental results to minimize the uncertain finiteelement modeling parameters of the historical masonry arc bridge such as material properties and boundaryconditions. At the end of the calibration process, the maximum differences between natural frequenciesobtained experimental measurements and numerical analysis decreases from 4%-50% to 0.5%-2.5%. Thefinal calibrated finite element model for the masonry bridge is able to produce natural frequencies in closeagreement with the measured ones.