Assessment of the Bill Emerson Memorial Bridge - FTP Directory ...

Table of ContentsExecutive summary...................................................................................................................... ivList of Figure Captions...................................... ........................................................................... xList of Table Captions ...............................................................................................................xiii1. Introduction............................................ ........................................................................... 11.1. General......................................... ........................................................................... 11.2. Bridge description........................ ........................................................................... 21.3. Seismic instrumentation system... ........................................................................... 61.4. Scope of work ......................................................................................................... 61.5. Significance of this study............ ............................................................................ 71.6. Organization of this report.......... ............................................................................ 72. Automatic Retrieval of Peak Accelerations from Real-time Seismic InstrumentationSystem ................................................................................................................................92.1. General.................................................................................................................... 92.2. Peak acceleration retrieval ...................................................................................... 92.2.1. Seismograms servers...................... ............................................................. 102.2.2. Which seismogram server to use?.. ............................................................. 102.2.3. Map/Find stations........................... ............................................................. 112.2.4. Query.............................................. ............................................................. 112.2.5. Displaying seismograms ............................................................................. 132.2.6. Saved data ................................................................................................... 153. Seismic Instrumentation System andMeasured Data Analysis.................................... ............................................................. 163.1. General.................................................................. ................................................ 163.2. Seismic instrumentation network.......................... ................................................ 173.3. Measured data ....................................................................................................... 193.3.1. Vertical vibration of the bridge deck .......................................................... 193.3.2. Transverse vibration.................................... ................................................ 213.3.3. Longitudinal vibration of the bridge tower. ................................................ 223.4. Data analysis method ............................................................................................ 263.4.1. General........................................................ ................................................ 263.4.2. Theory of Peak-Picking method ................................................................. 273.5. Measured data analysis ......................................................................................... 283.6. Mode shapes extracted from measure data ........................................................... 383.7. Remarks ........................................................ ........................................................ 404. Finite Element Modeling of Bill Emerson Memorial Cable-stayed Bridge............... 414.1. General.................................................................................................................. 414.2. Bridge geometry.......................................... .......................................................... 414.3. Material properties...................................... .......................................................... 424.4. Modeling of the main structural members.. .......................................................... 424.4.1. Towers............................................... .......................................................... 424.4.2. Girders............................................... .......................................................... 434.4.3. Cables................................................ .......................................................... 444.4.4. Connection bearings between towers and decks.... ..................................... 46viii