ANCOVA-based grouping of bridge classes for seismic fragility assessment. (15th September 2016)

• Record Type: Journal Article
• Authors: Mangalathu, Sujith; Jeon, Jong-Su; Padgett, Jamie E.; DesRoches, Reginald
• Is Part Of: Engineering structures. Volume 123(2016:Sep. 15)
• Page Start: 379
• Page End: 394
• Publication Date: 2016-09-15
• Subjects: ANOVA analysis of variance -- ANCOVA analysis of covariance -- BSST bridge system damage state -- C structural capacity -- CSP bridge sub-class with a circular single-column bent and two abutments on piles -- Caltrans California department of transportation -- CDT component damage threshold -- D structural demand -- JPSDM joint probabilistic seismic demand model -- IM ground motion intensity -- MPC bridge sub-class consisting of two multi-column bents, two abutments on piles, and clay backfill -- NLTHA nonlinear time history analysis -- PSDM probabilistic seismic demand model -- RSP bridge sub-class with a rectangular single-column bent and two abutments on piles -- Sa-1.0s spectral acceleration at a period of 1.0 s -- SPC bridge sub-class consisting of two single-column bents, two abutments on piles, and clay backfill; Analysis of covariance -- Regional seismic risk assessment -- Bridge inventory -- Concrete box-girder bridges -- Fragility curves; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2016.05.054
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Grouping of bridge classes for regional risk assessment. Identification of significant attribute-related parameters through analysis of covariance. Analysis of covariance-based grouping by comparing demands of bridge classes. Significant reduction in bridge classes compared to traditional subjective approach. Abstract: Fragility curves that can be applicable for vulnerability modeling of various configurations of structures, such as bridges, are required to facilitate regional seismic risk assessment. However, it is cumbersome and time-consuming to develop unique fragility curves for each structure across a regional portfolio. One strategy that has been adopted to address this challenge is to group bridges into classes with similar design or structural performance. Traditionally, this grouping has been performed based on a relatively subjective identification of sub-classes. However, such an identification leads to a number of bridge classes with unwarranted grouping. To overcome this limitation, a new grouping technique based on an analysis of covariance on probabilistic seismic demand models is suggested in this paper. The proposed analysis of covariance based grouping helps to identify important attribute-related parameters and to create distinct bridge sub-classes. The effectiveness of the proposed approach is demonstrated in this paper through case studies of four concrete box-girder bridges in California. This is the first systematic approach to sub-binning bridge classes for the regional risk assessment. The results suggest that the proposed grouping method significantly reduces bridge sub-classes from all possible sub-class combinations. The proposed method is relevant and can be applicable to other bridge types.