Practical Implementation of Generalized Force Vectors for the Multimodal Pushover Analysis of Building Structures

A practical implementation of generalized multimodal pushover analysis is presented in this study, where the number of pushovers is reduced significantly in view of the number of modes contributing to seismic response. It has been demonstrated in two case studies that the reduced procedure for generalized pushover analysis is equally successful in estimating the maximum member deformations and forces under a ground excitation with reference to nonlinear response history analysis. It is further shown that the results obtained by using the mean spectrum of a set of ground motions are almost identical to the mean of the results obtained from separate generalized pushover analyses. These results are also very close to the mean results of the nonlinear response history analyses, hence motivating the implementation of generalized pushover analysis with design spectrum

Lifetime resilience of aging concrete bridges under corrosion

The lifetime seismic resilience of deteriorating concrete bridges under corrosion is investigated. The time-variant seismic capacity is evaluated through a general methodology for lifetime assessment of concrete structures exposed to aggressive environments. The seismic capacity associated to different limit states, from slight damage up to collapse, is assumed as functionality indicator and seismic resilience is evaluated with respect to this indicator over the structural lifetime. The proposed approach is applied to a four-span continuous bridge with box cross-section piers exposed to corrosion. The results show that the amount of seismic damage and, consequently, the seismic resilience vary over time depending on structural deterioration