Seismic Risk Assessment of Dry‐Jointed Concrete Voussoir Arch in Highway Bridge

Abstract

Topologically interconnected dry‐jointed concrete voussoir arch (CVA) bridge is an emerging bridge typology in India for the construction of highway bridges. This study focuses on seismic risk assessment of a CVA bridge to evaluate its viability across various seismic zones in India. Seismic response of the bridge considered in this study is primarily governed by the response of voussoir arches, as the arches are supported directly on the foundation. The mechanics of load transfer in dry‐jointed voussoir arch is investigated, based on which the voussoir arch is idealized as a stacked assembly of rigid bodies. A discrete element modeling framework is employed to simulate its seismic response. Damage states for in‐plane and out‐of‐plane deformations of the arch are identified based on the margins available to maintain the line of thrust within the arch section. Seismic fragility functions of the bridge are developed through multiple stripes analysis with three‐component ground motions using a validated numerical model. Seismic risks of the bridge in different seismic zones are evaluated based on conditional probabilities of damage and mean annual frequencies of collapse. These risk parameters of CVA bridge are compared with those of reinforced concrete (RC) bridge piers, as well as with code‐defined performance limits. Results indicate that the CVA bridge exhibits lower capacities for slight and collapse damage states than RC bridge piers. The study finds that CVA bridges are suitable for construction of highway bridges in low seismic zones of India; however, they are vulnerable in high seismic zones.