Serviceability assessment of fatigued reinforced concrete structures using a dynamic response technique

摘要

Infrastructures such as bridges are often susceptible to continuous cyclic loadings and exposed to structural vibration. The cumulative cyclic loads will lead the structures into fatigue condition and contribute to the deficient service life of structures. Hence, evaluating the current structural health condition through the structural stiffness quantification is important. This study examined performance characteristics of fatigued RC slabs using an integrated dynamic response technique and numerical simulations by finite element (FE) model and model updating. The measured experimental results were used to update and validate the FE model. The results pertaining to the dynamic characteristics and structural stiffness show there is an inherent relationship with the fatigue damage. As the cyclic load increased, structural stiffness and natural frequency were found to decrease. The effects of a sensitive parameter of the slab structures were parametrically investigated, and an empirical formula derived from the results was established for evaluating the structural stiffness. An assessment method based on vibration-based is proposed and was demonstrated to be capable of predicting serviceability of fatigued RC structure.