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AutoAdaptive Media in Geotechnical Earthquake Engineering. Report of the Shoal Creek Discussion Group Research & Applications Austin, January 10-12, 2001. AutoAdaptive Media in Geotechnical Earthquake Engineering GENERAL RESEARCH AREAS. Seismic Ground Hazard Assessment
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AutoAdaptive Media in Geotechnical Earthquake Engineering Report of the Shoal Creek Discussion Group Research & Applications Austin, January 10-12, 2001 Shoal Creek Discussion Group
AutoAdaptive Media in Geotechnical Earthquake EngineeringGENERAL RESEARCH AREAS Seismic Ground Hazard Assessment Pre-Earthquake Hazard Mitigation Realtime EQ Monitoring & Seismic Response Post-EQ Health Monitoring & Detection Shoal Creek Discussion Group
Seismic Ground Hazard AssessmentFocus Areas Liquefaction Potential Landslides and Slopes Microzonation & Site-Specific Soil Properties Determination Site Response & Ground Amplification Shoal Creek Discussion Group
Pre-Earthquake Hazard MitigationFocus Areas Soil Densification and Improvement Foundation Systems Improvement Construction QA/QC Slope Stabilization Shoal Creek Discussion Group
Realtime Earthquake MonitoringFocus Areas Ground Motions (horiz. & vert. arrays) Porewater Pressures Permanent Deformations (GPS; Utilities made with smart alloys) GIS with all data monitors networked Shoal Creek Discussion Group
Post-Earthquake Health MonitoringFocus Areas Permanent Deformation Measurements Integrity Testing Soil and Rock Instability Residual Porewater Pressures Shoal Creek Discussion Group
Geotech EQE Problems & Needs Accurate measurements of low-strains in lateral load tests Measurements of soil stresses Dynamic Strain Measurements Soil Sampling of Clean Sands Calibrating Sensor In-Situ for Tornado Detection Shoal Creek Discussion Group
Geotech EQ Problems & Needs Measuring Strains Due to Blasting Pressure Transducers to Survive Blasts and still Measure Low-Pressures, Integrating Deflection Sensors Measurements of Pile Lateral Deflections, also Gaps Position Sensitive Detector (PSD) to Measure Displacement & Vibration Shoal Creek Discussion Group
Problems & Needs Array of sensors and receivers to measure changes in wave velocity during induced liquefaction Transducers to excite vibrocone (piezo-actuator) Deflection sensors matching ground impedance and density In-Situ Dynamic Strain & Damping Measurements Shoal Creek Discussion Group
Research & Solutions Using AAM • Installation of 3-D array of MEMs and/or Piezo Stacks for Tomographic Mapping of Vs during Liquefaction • Blast-Induced Liquefaction at Treasure Island/CA and Cooper River Bridge/SC Shoal Creek Discussion Group
Research & Solutions Using AAM • Liquefaction Effects on CPT qc and in-situ Vs • Time effects on qc and Vs after liquefaction • Arrays of MEMs and Piezoelectric Stacks (BE) Shoal Creek Discussion Group
Sampling Methods • Magneto-Rheological Drilling Fluids • Impregnates clean sands for undisturbed samples until confined within triaxial apparatus Shoal Creek Discussion Group
Site Characterization Methods • Vibrocone Penetrometer for Site-Specific Liquefaction Evaluation • Dynamic Forces imparted by piezostack for controlled frequency, displacements, & loads. Shoal Creek Discussion Group
Advanced Geotechnical Exploration • Opto-electro-mechanical sensors with digital output for subsurface image collection at variable focal lengths. • Enhancement on the VisCPT concept for high-resolution stratigraphic profiling. Shoal Creek Discussion Group
Lifeline/Utility Connections • Shape-memory alloys s e Shoal Creek Discussion Group
Advanced Reinforced Earth Structures • Use principles of active dampers from buildings to reinforced earth retention walls & embankments. • Piezo-polymer geosynthetics (“smart geosynthetics”) Shoal Creek Discussion Group
AAM Ground Improvement • During seismic event, Smart System controls pump drawdown from wells to reduce excess porewater pressures. • Vacuum consolidation Shoal Creek Discussion Group
Self-Diagnosing Foundation System • Fiber optics and/or Time Domain Reflectometry (TDR). • Self-Leveling Foundation Systems Shoal Creek Discussion Group
Need Permanent DeformationMeasurement Devices • GPS • Measure barometric pressures with AAM ? • PSD (position sensitive detector) • SAR (remote sensing) • TDR Shoal Creek Discussion Group
Permanent Deformations • Network System of Motes (Glaser) • Each Mote connected to a vertical or angled fiber optics sensor (hybrid AAM) Shoal Creek Discussion Group
Centrifuge Modeling with MR fluid soils • Where do the sand particles go when liquefaction occurs • Use sand with mixed magneto-rheological properties • Magnetic sensing tools to trace where the sand flowed Shoal Creek Discussion Group