California RC Bridges 2025 (Chen et al.): Components

Component-level seismic fragility models for California reinforced concrete bridges from the database of Chen et al. (2025), Earthquake Spectra 41(4), doi:10.1177/87552930251343634, published on DesignSafe as PRJ-5910 (doi:10.17603/ds2-c73m-nj37, version 1, Open Data Commons Attribution License).

The database compiles fragility curves from published studies and assigns them to 26 bridge groups. Curves for the same component within a group come from different studies and are alternatives; the database publishes no weights for choosing among them. The Cavalcante et al. (2022) curves in the E123 groups (single-span bridges) are, or are derived from, curves for Brazilian bridges, which Chen et al. (2025) use as a proxy for California single-span bridges; the approach-settlement curves of Shao et al. (2022) in those groups are for California bridges. Chen et al. (2025) found no era-specific fragility models for single-span bridges, so the E123 groups apply to bridges of any era.

A group code gives four properties of the bridge:

  • the design era: E1 pre-1970, E2 1971–1990, E3 post-1991, E123 any era;

  • the number of spans: S1 one, S2 two, S3P three or more;

  • the bent type: C0 no bents, C1 single-column bents, C2P multi-column bents;

  • the abutment type: D diaphragm, S seat.

Model IDs follow the pattern CRCB.<era>.<spans>.<bents>.<abutment>.<component>.<attributes>.<source>, where the attributes describe the deck, the bent configuration (two-column, or three to five columns), the modeled span count, frames, in-span hinges, column shape, direction, modification basis, abutment foundation, and approach slab, and the last segment names the source study.

Each curve gives the probability of reaching or exceeding a damage state as a function of Sa(1.0 s), the spectral acceleration at a period of 1.0 s, in g.

The component fragilities of this dataset and the system fragilities of the ‘California RC Bridges 2025 (Chen et al.): Systems’ dataset (seismic/transportation_network/portfolio/California RC Bridges 2025) are two representations of the same bridge. Apply one or the other to a given bridge, because applying both to the same bridge double-counts its damage; different bridges in one regional assessment may use different representations. Entries that are N/A in the slight and moderate median and dispersion, the only states their components define, with the extensive and complete cells empty, are omitted: 71 column foundation rotation (FndRot) entries, all those in the 24 groups where the component occurs except 1 of the 4 in E1-S2-C2P-S; 24 shear key (Key) entries, all those in E2-S2-C1-S, E2-S2-C2P-S, E2-S3P-C1-S, E2-S3P-C2P-S, E3-S2-C1-S, E3-S2-C2P-S, E3-S3P-C1-S, and E3-S3P-C2P-S. The database uses N/A to mark a negligible probability of damage from ground shaking. The Comments of each model record the source study, its ground-motion suite, and every correction or inherited value.