Wind Tunnel Tests And Field Measurements Of Wind-induced Vibrations On Tall Buildings

With the rapid urbanization and centralization of city population in china, more and more tall buildings have developed in recenet years. As tall buildings have the characteristics of light mass, more flexibility, small damping and low natural frequencies, wind load has become the controlling load for the structural design of such tall buildings. As we know, wind tunnel test and field measurement are two major methods for wind engineering society. Taking Guangzhou Leatop Plaza as an example, the wind effects on this tall building was comprehensively studied in this dissertation by these two methods. The main content of this dissertation were listed as the following:1. First the Multiple Point Synchronous Scanning (MPSS) test of wind pressure and High-Frequency Force Balance test (HFBB) were conducted in the wind tunnel. The overturning moments at basement, peak acceleration response atop of the building and equivalent static wind load (ESWL) for this tall building were analyzed based on the wind tunnel data. A comparison of wind-induced responses has been made between these two wind tunnel test methods. The reliability of the test data has been verified.The analyzed results from wind tunnel tests would establish the valuable reference for the wind resistant design of such tall buildings.2. A continuous structural vibration monitoring was conducted for a long-term period when typhoon affected this tall building.The field measured data about the typhoon characteristics atop the building was obtained. The statistically results about the probability distribution, power spectrum density and turbulence integral scale of fluctuating wind speed were analyzed. Furthermore, the relationship between turbulence intensities, gust factors and wind speed were also studied in this project.The analyzed results would provide valuable information for further research into wind climate, wind field simulation, and wind load design.3. During the typhoon affected this tall building, wind speed atop of the building and wind-induced responses were measured and recorded synchronously.The dynamic characteristics including natural frequencies, damping ratios and wind-induced acceleration response have been analyzed for this tall building based on the measured data.Thus information about the wind effects on this tall building was obtained comprehensively. Furthermore the variation of identified natural frequencies of this tall building during the construction process was also analyzed to provide the more information of dynamic characteristic of such tall buildings in various construction stages.