VShaker Metadata

VShaker Metadata

This page describes the information content used with VShaker system. The VShaker system is described in more detail on the Virtual Shaker pages. Detailed development information is posted on the IT web site at: [IT Site]

VShaker metadata is based on the idea of data set. A data set is a collection of one or more data files. VShaker will deliver a metadata file per data set. This metadata file provides a description of the data set. VShaker metadata files are constructed in a way that they can be aggregated without duplicating information. This is done in aggregrates through references to existing metadata files. The result of this is that there is one primary metadata file per dataset, and that may reference other metadata files which will also be included in the distribution.

VShaker datasets use a standard directory structure that contains some or all of the following directories:

• Inputs
  • Original 3 component seismograms
  • Acceleration input to Virtual Shaker
  • decimated 3 component sesimograms
  • trimmed seisomgrams
  • acceleration trimmmed

• Outputs
  • Series of obj files
  • mtl file
  • animation
  • raw VirtualShaker Output files
  • Node velocity or seismogram files

Example of Existing Automated Metadata

The existing automated Vshaker metadata system produces the following "key/value", or attribute name/attribute value pairs. The attribute names must be unique. The values are all strings and must be converted to appropriate data types by parsers. Currently the metadata pairs are comma delimited.

• 'Total Frames': 1601,
• 'Frame Start': 0,
• 'Frame End': 1600,
• 'Frame Interval': 1,
• 'Time Interval': 0.23,
• 'Title': 'M8 Simulation: Northridge',
• 'Up Axis': 'Z',
• 'OBJ Units': 'in',
• 'OBJ Scale': '0.01',
• 'OBJ filename': '20100923-122539_####.obj'
• 'OBJ material filename': '20100923-122539.mtl'
• 'Simulation ID': '20100923-122539',
• 'Earthquake Description': 'SCEC M8 San Andreas Earthquake Simulation: Northridge',
• 'Coordinate LON LAT': '-118.531250 34.218750',
• 'Coordinate UTM_E (m) UTM_N (m)': '386544.244357, 4097025.437890',
• 'Coordinate OFFSET_E (m) OFFSET_N (m)': '383817.979601 121914.266513',
• 'Coordinate Extent': '(-120.4, -114.4), (31.5, 36.2)',
• 'Coordinate Origin': '(-117.8, -117.7), (34.6, 34.6)',
• 'Simulation Date': '2010-09-23',
• 'Simulation Time': '12:25:39',
• 'Max Displacement (in)': 240.6357465132725,
• 'Structural Motion': 'Absolute',
• 'Relative Motion Exaggeration': 5.0,
• 'Ground Motion Exaggeration': 5.0,
• 'GAMULTX': 39.3701,
• 'GAMULTY': 39.3701,
• 'GAMULTZ': 39.3701,
• 'Node Color Map':'0.0 0.0 1.0 0.0 1.0 120 1.0 0.0 0.0 1.0',
• 'Node Color Map Steps': 10,
• 'Structural Model Name': '18-Story UBC 82 Building (Units = kip-in)',
• 'Structural Model Description': 'This building is located in Woodland Hills, within five miles of the epicenter of the 1994 Northridge earthquake. The east, west, and south moment frames lie on the perimeter of the building, while the north frame is located one bay inside of the perimeter. This gives rise to some torsional eccentricity. Many moment-frame beam-column connections in the building fractured during the Northridge earthquake, and the building has been extensively investigated since then by many engineering research groups (SAC 1995b, Carlson 1999). Detailed floor plans, beam and column sizes, and gravity, wind, and seismic loading criteria are given in Krishnan et al. 2005. A36 steel with nominal yield strength of 248.29 MPa, (36 ksi) is used for all beams, while A572 Grade 50 steel with nominal yield strength of 344.85 MPa (50 ksi) is used for all columns. The floors consist of lightweight concrete slab on metal deck supported by steel beams and girders framing into gravity and moment-frame columns. The model includes a probabilistic distribution to describe the fracture strain for fibers in the bottom-flanges of the moment frame beams.\n'