Structural system identification in time domain using measured acceleration

This paper presents a system identification scheme in time domain to estimate stiffness and damping parameters of a structure using measured acceleration. An error function is defined as the time integral of the least-squared errors between measured accelerations and calculated accelerations by a numerical model of a structure. To alleviate the ill-posedness of SI problems a regularization technique is employed and a new regularization function for the time-domain SI is proposed. The regularization factor is determined by the geometric mean scheme. The validity of the proposed method is demonstrated by a numerical simulation study on a two-span truss bridge and by an experimental laboratory study on a three-story shear building model.