Application of VD-LRBP system for bridges in seismic zones
Conference
Dolati, SSK, Mehrabi, A, Dolati, SSK. (2022). Application of VD-LRBP system for bridges in seismic zones
. SMART BIOMEDICAL AND PHYSIOLOGICAL SENSOR TECHNOLOGY XI, 12043 10.1117/12.2612742
Dolati, SSK, Mehrabi, A, Dolati, SSK. (2022). Application of VD-LRBP system for bridges in seismic zones
. SMART BIOMEDICAL AND PHYSIOLOGICAL SENSOR TECHNOLOGY XI, 12043 10.1117/12.2612742
Laminated rubber bearing pad (LRBP) is widely used in small to medium-span highway bridges. They are directly placed between piers and girders to allow the bridge span to have horizontal movement and to transfer the gravity loads from decks to piers. Although LRBPs are not designed for seismic loads, their application can partially isolate the superstructure from the substructure keeping the piers intact during earthquake events. However, recent investigations indicate that large relative displacement between superstructure and substructure caused by sliding between girders and LRBPs can cause expansion joint or bridge span failure. As such, suitable restrainers should be implemented to control the potential large displacement. Among all types of restrainers, passive energy devices such as viscous dampers have shown a remarkable capacity in dissipating the earthquakes energy. This study aims at investigating the effectiveness of VD-LRBPs system, viscous dampers in conjunction with LRBPs, in controlling the large displacement between decks and piers. Accordingly, a 3D Nonlinear Time History Analysis (NTHA) was conducted on a case study RC bridge model under several earthquakes. OpenSees, an open sources finite element software, was used for the analysis. The relative displacements between decks and piers as well as the force in the piers, were recorded for two cases: 1- with only LRBPs and 2- with viscous dampers and LRBPs (VD-LRBP system). The results indicate that adding viscous dampers can reduce the relative displacement up to 60 percent. Also, it can reduce the potential residual displacement post-earthquakes to near zero.
