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Measuring relative-story displacement and local inclination angle using multiple position-sensitive detectors
Iwao Matsuya1, Ryuta Katamura, Maya Sato
1Faculty of Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo, Japan. matsuya@aoni.waseda.jp
Sensors (Basel, Switzerland)
|December 14, 2011
Summary
This study introduces a novel optical sensor system for monitoring building structural health. It precisely measures relative-story displacement and inclination during seismic events, ensuring building safety.
Area of Science:
- Structural Engineering
- Geotechnical Engineering
- Sensor Technology
Background:
- Accurate monitoring of building structural health during seismic events is crucial for safety.
- Existing methods for measuring relative-story displacement may lack precision under dynamic conditions.
Purpose of the Study:
- To develop and validate a novel optical sensor system for precise measurement of relative-story displacement and inclination during earthquakes.
- To assess the system's accuracy and reliability for structural health monitoring applications.
Main Methods:
- The proposed sensor system utilizes three position sensitive detectors (PSDs) and lenses for optical measurement.
- Laboratory verification involved static tests using an Xθ-stage and dynamic tests on a shaking table.
Main Results:
- Static experiments confirmed the sensor's capability to measure both local inclination angle and lateral displacement.
- Dynamic experiments demonstrated high accuracy, achieving 150 μm for relative-displacement and 100 μrad for inclination angle measurements.
Conclusions:
- The developed optical sensor system offers sufficient accuracy for measuring relative-story displacement and inclination during seismic vibrations.
- This technology has the potential to significantly enhance building structural health monitoring systems.
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