Computational Simulation for Earthquake Engineering Research and Practice

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Computational Simulation for Earthquake
Engineering Research and Practice

• Frank McKenna and Gregory L. FenvesUniversity of
  California, Berkeley
• Sponsored by
• National Science Foundation
• NEESit NEES Cyberinfrastructure Center at SDSC
• Pacific Earthquake Engineering Research Center

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Context for Simulation in Earthquake Engineering

• Research and practice is moving towards
  Performance-Based Earthquake Engineering.
• Development of enabling technology is expected of
  NSF research centers, utilizing national
  cyberinfrastructure resources.
• Community-based, open-source software for
  simulation allows innovation in research and
  provides advanced applications for practice.
• NEESit is supporting OpenSees to provide
  simulation capability and integration with NEESit
  services for NEES research.

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Vision for Computational Simulation
Computational modeling and simulation is central
to the vision of NEES to transform the
development of new earthquake engineering
solutions from being primarily based on
experiments to a balanced use of simulation and
experimentation using computational models
validated by experimental data.
A close integration of modern computational
models and simulation software with other NEES
applications and services will provide the
earthquake engineering community, and broad
engineering users, new capabilities for
developing innovative and cost-effective
solutions.
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User Need Assessment for Simulation
Polls at 4th NEES Annual Meeting, June 2006

• Priorities for vision of NEES IT
• top priority 44 data, 16 simulation
• One of top three priorities 77 data, 72
  simulation,54 collaboration
• Important to long-term legacy 32 simulation,
  24 data
• ITSC theme session
• What simulation software would you use on HPC
  26 OpenSees, 26 ABAQUS not interested 25
• NEESit provides excellent simulation and
  visualization tools 17 agree or strongly agree,
  11 neutral, 33 disagree or strongly disagree,
  39 cant evaluate.

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Observations on Current Situation

• Tight binding of models in research and
  commercial codes is an impediment to new research
  and implementation of models for professional
  practice.
• Embedding of computational procedures in codes
  makes it difficult to experiment and take
  advantage of computing technology
• Parallel and distributed computers
• Computational grids

• Closed-source is the norm, whereas other fields
  have adopted open-source software for
  communitiesusers.

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Conceptual Approach for Simulation
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Software Framework

• A framework is not a code, it is not an
  executable, it is not a library.
• A framework is a set of cooperating software
  components for building applications in a
  specific domain.
• A framework dictates the architecture of the
  application. It must represent the design
  decisions common to the application domain.
• A frameworks is based on the assumption that an
  architecture will work for most applications
  within the domain.
• Loose-coupling of components within the framework
  is essential for extensibility and re-usability
  of applications.
• Examples Visualization (GLUT), MS Office,
  compilers ...

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Simulation Software Alternatives
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http//opensees.berkeley.edu

• OpenSees has been under development by PEER since
  before 1997.
• Large group of developers and user.
• PEER and NEESit support development for
  simulation applications in OpenSees.
• Open-source and license for non-commercial and
  commercial use (excludes commercial sale).

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OpenSees Approach to Simulation

• Basic approach
• Modular software design for implementing and
  integrating modeling, numerical methods, and IT
  for scalable, robust simulation
• Open-source software for building a community of
  users and developers
• Focus on capabilities needed for
  performance-based engineering
• Most users a code for nonlinearanalysis
• Generally a software framework for developing
  simulation applications

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Simulation Software Alternatives
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Structural Models as Aggregation Pattern
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Analysis Class for Simulation
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Beam-Column Models
Material
No assumptions are made on section or material
behavior each level in the hierarchy can be
defined independently of other levels
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Form Follows Mechanics
Material
s
ForceDeformation
UniaxialMaterial
e
s
Steel01
Concrete01
e
as 1 y z
FiberSection
Fiber
2
BeamWithHinges
UniaxialFiber
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Framework Design/Sourcefor Developers
Class Specification Application Program Interface
Source Code Viewing/Updating With CVS
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Windows Executable Download
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Scripting Models
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OpenSees On-Line Documentation
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Downloaded Documentation
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OpenSees Examples Manual
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(No Transcript)
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(No Transcript)
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(No Transcript)
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OpenSees Building Analysis
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NEESit High-Performance Computing

• OpenSees implementations
• High-fidelity site response by DRM
• Teragrid allocation and usage
• NEES wide 50,000 SUs(OpenSees, ABAQUS, Adina,
  LS-Dyna)
• 22 projects have access to allocation
• Humboldt Bay Bridge example
• NEESsphere

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NEESit Services SimPort
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NEESit Services NEEScentral

• Command will be in OpenSees to upload data
  

neesUpload project pID? simulation simID? User
name? pass
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OpenSees and Scientific Workflows

• OpenSees code has been integrated with kepler, a
  system for design, execution and deployment of
  workflows.

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OpenSees Community Forum
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What Should be Your Expectations?

• OpenSees is a research tool at this time, but
  fairly stable for regular use
• As with any nonlinear analysis, it requires
  careful consideration of model and interpretation
  of results
• It is under continual development by students,
  faculty and other researchers
• User interface development lags behind
  computational technology
• It is not bullet-proof
• An investment of time and learning is required
• The OpenSees open-source community requires
  greater contributions from the community to be
  more successful.