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

System-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. Each curve is a series-system fragility that the source study derived from correlated component demands. Curves within a group come from different studies and are alternatives; the database publishes no weights for choosing among them. The single-span curves (E123 groups) come from, or are derived from, curves for Brazilian bridges, which Chen et al. (2025) use as a proxy for California single-span bridges. 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>.System.<attributes>.<source>, where the attributes describe the deck, the bents, the modeled span count, frames, column shape, and modification basis, 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 system fragilities of this dataset and the component fragilities of the ‘California RC Bridges 2025 (Chen et al.): Components’ dataset (seismic/transportation_network/component/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. The Comments of each model record the source study, its ground-motion suite, and every correction.