July 16, 2018
The NHERI SimCenter has just released three research tools and its third educational tool that support natural hazards engineering. Details of the tools and apps are below.
EVW application allows the user to compare the responses of buildings subjected to earthquake and wind loading. The user models the building including floor weights, story properties, and geometry to observe structural dynamics in a side-by-side loading comparison. Earthquakes are selected from a series of predefined ground-motion acceleration records or user-provided motions. Wind forces are determined at floor levels using a stochastic process that takes into account gust speed, exposure category, drag coefficient, and building height and width. Building dynamic properties, base shear, and moment diagrams are produced along with the visual time-history response in the graphical user interface.
3 RESEARCH TOOLS
The Computational Wind Engineering (CWE) tool is computational fluid dynamics (CFD) analysis software based on OpenFOAM for analyzing the effect of wind on rigid body structures and attendant response. It interfaces with HPC resources at DesignSafe-CI to perform the CFD calculations and alleviate computational overhead from the user’s local machine. The ability to include user-defined inflow conditions and future releases that account for uncertainty quantification are intended to support and enhance CWE research.
This application advances the use of uncertainty quantification in the field of natural hazards engineering by combining existing finite element (FE) applications with uncertainty quantification (UQ) applications behind a simple user interface. Using this app, an engineer can apply UQ methods to a new or existing FE model by identifying and flagging the random variables of interest. To overcome the issue of computational overhead, which typically precludes these types of probabilistic analyses from being performed, the user has the option of specifying that the simulations take place on HPC resources, such as the TACC Stampede supercomputer available through DesignSafe-CI, instead of executing them on their local machine.
Regional Earthquake Workflow and Testbed
The Regional Earthquake Workflow is the first demonstration of the SimCenter’s Application Framework that supports natural hazards engineering research. The extensible framework is next-generation software aimed at advancing regional-scale simulations. The applications framework includes specifications for building information models, hazard events, loss calculations, and the APIs that interface between other applications that perform simulations. While the workflow is designed for HPC, a local version supports development and testing.
The developed Regional Earthquake Workflow is used to study the effects of earthquakes on society at the regional scale. One demonstration of the Workflow is the SimCenter’s Earthquake Testbed, which evaluates a M7.0 earthquake’s impact on the San Francisco Bay Area. Accounting for the region’s 1.8 million buildings, damage and loss for the region are calculated from fragilities and software provided through the user community. Although the testbed is comparable to similar regional hazard scenarios, this one is intended to inspire the user community’s adaptation and expansion of the workflow into their research.
To learn more about the testbed, expanding workflow capabilities, or extending to other hazards, please contact NHERI-SimCenter@berkeley.edu.
The NHERI Computational Modeling and Simulation Center (SimCenter) provides researchers access to next-generation computational modeling and simulation software tools, user support, and educational materials needed to advance the capability to simulate the impact of natural hazards on structures, lifelines, and communities. The SimCenter’s cyber-infrastructure framework allows collaborative simulations from various disciplines to be integrated, while accounting for pertinent sources of uncertainty.