摘要
Field measurement is the most reliable method to evaluate wind effects on super high-rise building; it is also the only approach to obtain actual structural dynamic properties. A self-developed wireless acceleration sensor was used to continuously monitor a 201 m high building in Shenzhen, and acceleration response signals atop the building during Typhoon Pakhar and Typhoon Mangkhut were obtained. The field data of approximately 58 hours were analyzed using random decrement technique and modified Bayesian spectral density approach, and the variation characteristics of the first two-order modal frequencies and damping ratios of the measured building under strong vibrations were obtained. Finally, field measurements of the maximum peak accelerations were compared with wind tunnel test results. Results show that (1) the frequencies decrease with increasing amplitude. In addition, they decreased initially and then increased with time, showing a "V" shape change. The maximum change rate of the frequencies was 11.5%. (2) During Typhoon Pakhar, the damping ratios were discrete. During Typhoon Mangkhut, the damping ratios increased with increasing amplitude in general, but the damping ratios were relatively discrete at small amplitudes. During Typhoon Mangkhut, the damping ratios increased initially, and then decreased with time. In addition, the first two-order damping ratios during the maximum wind speed were approximately 1.7% and 1.5%. (3) The wind tunnel test results are in good agreement with the field measurement results, thereby verifying the reliability of the wind tunnel test.
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单位广州大学