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This paper presents the analytical formulation and computational implementation of a conceptual probabilistic performance-based seismic design (PBSD) framework for ordinary standard bridge (OSB) structures. An updated probabilistic performance-based earthquake engineering (PBEE) assessment methodology is used for the parametric performance assessment of four distinct OSBs in California to investigate the effects of varying key structural design parameters over a primary design parameter space on risk-based structural performance measures. The dire need for a systematic PBSD framework for OSBs is illustrated given the significant variability in risk-based performance levels exhibited by these traditionally designed testbed OSBs. A PBSD methodology involving the design of the bridge piers is proposed wherein a risk-based feasible design domain in the primary design parameter space is identified which facilitates the risk-informed design/decision making process in the face of uncertainty. Sensitivities of risk-based feasible design domains compared with other (secondary) design variables and with the method employed for damage hazard assessment are investigated. [ABSTRACT FROM AUTHOR]

This paper presents the formulation of a comprehensive risk-targeted performance-based seismic design (PBSD) framework involving the seismic design of bridge piers for California Ordinary Standard Bridges (OSBs), facilitating risk-informed design and decision making in the face of uncertainty. A full-fledged implementation of this all-inclusive design method formulated by retaining the inherent rigor of the underlying seismic performance assessment methodology might impose a seemingly prohibitive computational cost for the available resources in the current scenario of seismic bridge design practice. For reasons of practicability, the findings of the full-fledged design framework are inventively utilized to distill out a simplified and computationally more economical PBSD procedure. Its efficacy is validated using four already-built California testbed OSBs as cases in point. The proposed simplified design methodology is able to (1) find a design point in the primary design parameter space of a bridge to be designed for multiple risk-targeted performance objectives; and (2) delineate an approximate, yet sufficiently accurate, feasible design domain and identify the limit states controlling its boundary in the primary design parameter space of the bridge, at a computational cost significantly lower than that of the original method. [ABSTRACT FROM AUTHOR]

With the recent advent of performance‐based earthquake engineering (PBEE) in seismic design practice of buildings serving as an impetus for this work, initial steps toward a fully probabilistic performance‐based seismic design (PBSD) method for bridges, a less trodden area in terms of PBEE applications, are taken herein by assembling an updated probabilistic seismic performance assessment framework for ordinary standard bridges (OSBs) in California. The framework stems from the comprehensive PBEE methodology developed under the auspices of the Pacific Earthquake Engineering Research (PEER) Center. With performance measures defined as the risk associated with the exceedance of a set of damage/limit‐states (LSs), improvements from the state‐of‐the‐art literature on the PEER PBEE methodology are incorporated, including (1) introduction of an improved intensity measure ‐ average spectral acceleration over a period range, (2) conditional mean spectrum‐based hazard‐consistent and site‐specific ground motion selection, (3) introduction of material strain‐based engineering demand parameters, (4) use of practical LSs pertinent to seismic damage evaluation of bridges, and (5) development of strain‐based normalized fragility functions for the considered LSs. The updated framework, assembled herein using a specific testbed California OSB as a case in point, is general within its scope and is applicable to the gamut of design situations representative of the population of OSBs in California. With the PEER PBEE framework implemented for OSBs in an updated and rigorous form, the groundwork for utilizing this framework in the context of PBSD of such bridges is laid. [ABSTRACT FROM AUTHOR]