Seismic Performance of Sacrificial Exterior Shear Keys in Bridge Abutments

Abstract

Performance evaluation of sacrificial exterior shear keys in bridge abutments under simulated seismic loading was conducted in terms of damage levels that were observed during testing. These experiments provided results that were used to make realistic assumptions on the load-deformation response of as-built sacrificial exterior shear keys as well as their peak and post-peak performance under cyclic loads. Experimental results were subsequently used to develop a two-spring component hysteretic model for modeling the seismic response of shear keys at the abutments. The mathematical rules used to describe the hysteretic model are presented. Analyses show that this model was able to reproduce reasonably well the cyclic response of the investigated keys. The hysteretic model and key experimental results are presented in this paper.

Stripe‐based fragility analysis of multispan concrete bridge classes using machine learning techniques

“…Ramanathan 7 indicated that these bridge types occupy more than 40% of the California box-girder bridge inventory. The response of the abutment piles is simulated using a trilinear material model presented in Mangalathu et al 11 Exterior shear keys are simulated following the backbone curve of experimental results by Silva et al 31 The foundations are modeled using linear translational and rotational springs. Decks are modeled using linear elements and are connected to columns with rigid links.…”

“…The hyperbolic soil model proposed by Shamsabadi et al 30 is used to simulate the passive response of the abutment. The response of the abutment piles is simulated using a trilinear material model presented in Mangalathu et al 11 Exterior shear keys are simulated following the backbone curve of experimental results by Silva et al 31 The foundations are modeled using linear translational and rotational springs. The various components previously described are combined to generate the bridge system model for seismic fragility analysis, and the spring connection for the various components is also shown in Figure 2.…”

Performance‐based grouping methods of bridge classes for regional seismic risk assessment: Application of ANOVA, ANCOVA, and non‐parametric approaches

“…Although a detailed description of the analytical modeling technique for this class of bridges can be found elsewhere [4,5,16], the general approach is presented herein. The shear key model is based on the experimental work of Silva et al [22]. The superstructure is modeled as a spline using elastic beam-column elements as it typically remains elastic during a seismic event, and the transverse deck elements are modeled as rigid elements.…”

“…A frictional response model (elastic-perfectly plastic bilinear material model) is used to capture the behavior of abutments on spread footings. The shear key model is based on the experimental work of Silva et al [22]. The typical configuration of the selected box-girder bridge and associated numerical model of various bridge components are shown in Figure 3.…”

Modelling of shear keys in bridge structures under seismic loads

“…sliding shear failure and diagonal shear failure, were identified for exterior shear keys. Silva et al performed experimental and analytical investigations to evaluate the seismic performance of sacrificial interior [13] and exterior [14] shear keys. Rational models of the force and deformation capacity of shear keys as well as their postpeak performance under cyclic loads were proposed based on the experimental data.…”