An Analysis of Modal Pushover on a Multi-Span Bridge to Assess Seismic Responses (KEY IJP************425)

• Avinash Kumar,Dr. Jyoti Yadav

Abstract

Performance-based seismic design is increasingly incorporating nonlinear static procedures due to the comparatively straightforward method they offer for estimating inelastic structural response measures. Nevertheless, traditional nonlinear static methods that rely on lateral load patterns as suggested in FEMA-356 fail to sufficiently capture the consequences of fluctuating dynamic properties during the inelastic response or the impact of higher modes. In light of these limitations, a number of researchers have recently put forth enhanced methodologies. This paper investigates a method of modal combinations that implicitly accounts for higher mode effects. The modal pushover analysis method utilizes factored combinations of independent modal contributions to generate invariant force distributions. This study examines the efficacy of Modal Pushover Analysis (MPA) in forecasting the inelastic seismic behavior of a multi-span concrete bridge. Lateral forces acting on the bridge are proportionally distributed across its span in accordance with the product of mass and displaced shape. The target displacement is calculated using the peak displacement of the nth mode inelastic Single Degree of Freedom System to elevate the structure.