Analysis of the Seismic Behavior of a Wall Pier of a Covered Bridge Based on the Multi-Layer Shell Element

Abstract

To investigate the seismic behavior of the wall pier of a covered bridge, the multi-layer shell element in OpenSEES was used to carry out the numerical analysis under a horizontal low cyclic loading in the weak axis direction. The effects of the mesh divisions of the wall pier models were evaluated and the hysteretic curves, skeleton curves, bearing and energy dissipation capacity, stiffness degradation and displacement ductility of the wall pier with different lateral loading modes were mainly researched. The results demonstrate that the discretization of layers along the thickness direction of the multi-layer shell element model has a very limited effect on the hysteretic and skeleton curves. The mesh division of the horizontal direction depends on that of the vertical, and the vertical mesh spacing shall be longer than the plastic hinge with a length of 0.5744 m. The arrangement of the loading points is critical for the seismic behavior of the wall pier. The pier suffering the force from the five points presents a relatively strong energy dissipation and larger ductility, but this layout may cause a more concentrated force at the local position. When the loading points are evenly distributed, the capacity and displacement changes sharply and the ductility diminishes. Successively, the seismic performance indexes at the local position of the wall pier tend to be more consistent with the increasing loading points. The deformation and energy dissipation capacity of the nearby position with the denser side loading points becomes larger, but this has a minor impact on the seismic performance of the position far from the points. The wall pier without the bent cap and with three bearings set is supposed to be more reasonable for the covered bridge through the overall analysis of seismic performance.

Digital twin-based life-cycle seismic performance assessment of a long-span cable-stayed bridge

“…Compared to beam-column elements in many other studies, shell elements could provide more intuitive modeling of the rectangular hollow section towers of the physical bridge, especially the beam-column conjunction areas. Furthermore, the use of shell elements for simulating seismic behaviors of pylons and piers of bridges has also been widely validated in many other studies (Son & Lee 2011;Li et al 2018;Lin et al 2021b;Qiu et al 2022). The shell elements contained both concrete and steel layers to simulate the composite material behavior of reinforced concrete components (Lu et al 2013), whose thickness was determined based on the sectional reinforcement details as shown in Fig.…”