Analysis methodology for dynamic structural behaviour modelling of highway bridges based on Monte Carlo simulations (MCS) considering vehicle-pavement-bridge interaction

Purpose To develop an analysis methodology to evaluate the dynamic behaviour and fatigue assessment of highway bridges due to vehicle passage on irregular pavement surfaces. The approach considers the non-deterministic nature of the parameters of the vehicle-bridge system using Monte Carlo simulations. Design/methodology/approach In the proposed approach, 11 vehicle-bridge system parameters are modelled as random variables with predefined probability distributions. The dynamic analysis considers the vehicle-structure-pavement interaction, in which road surface roughness is defined based on the use of the power spectral density function, as an expression of the road surface random irregularities. Based on the results of the dynamic analysis, a fatigue assessment is performed. To demonstrate the applicability of the methodology, a case study of a 40-m-span steel-concrete composite highway bridge was selected, considering two levels of pavement quality. Findings The results reveal that vehicle speed, sprung masses, bridge mass and rear axle and tire stiffness are the parameters that most influence vertical displacement, bending stress and fatigue life. Numerical simulations showed that the pavement deterioration reduced fatigue life by up to 98.6%, increasing the failure probability. Originality/value The dynamic behaviour and fatigue of a highway bridge are evaluated by means of vehicle-structure interaction analyses, in which the randomness of 11 parameters of the vehicle-bridge system is simulated. This includes dynamic parameters of the suspension and tires, whose variability is rarely considered due to the difficulty in obtaining sample data.