SCEC Broadband Platform: System Architecture and Software Implementation

Online Material: Text‐based (BBP) input and output files and figures of goodness of fit; seismogram comparisons and source model illustrating the BBP validation of the Loma Prieta earthquake. The Southern California Earthquake Center (SCEC) Broadband Platform (BBP) is an open‐source software distribution that contains physics‐based ground‐motion models capable of calculating earthquake ground motions at frequencies above 10 Hz across regional distances. In addition, the BBP contains software tools for evaluating ground‐motion models and comparing simulation results to observed ground‐motion recordings and against ground‐motion prediction equations (GMPEs). The BBP also includes software utilities that help users run large numbers of ground‐motion simulations and manage the simulation results. Several of the ground‐motion simulation methods included in the BBP are described in related articles in this special focus issue. In this article, we describe how the BBP system architecture and software implementation support the scientific and engineering processes needed to assess ground‐motion models for use in engineering applications. The BBP design and development was initiated after a number of promising broadband ground‐motion simulation methods were developed (e.g., Atkinson and Boore, 2003; Boore and Atkinson, 2008; Graves and Pitarka, 2010; Mai et al. , 2010; Schmedes et al. , 2010). Researchers were interested in comparing ground‐motion simulation results between methods and in comparing simulation results to observations and to GMPEs. Such comparisons can be difficult because alternative methods often require different input parameters or specify input parameters in dissimilar formats. Fair comparisons between methods are only possible once multiple methods can input equivalent problem definitions and output comparable results. Based on previous experience evaluating simulation methods, seismologists and earthquake engineers recognized a need for a software tool to support the evaluation of the newly emerging broadband simulation methods. Drawing on discussions with both seismologists and engineers (e.g., Jordan and Maechling, 2003; Maechling …