Wind Tunnel Investigation on the Motion Coupled Aeroelastic Behavior of Highrise Buildings(2)

• Main Authors: LO, Hsin-Yi, 羅信沂
• Other Authors: Cheng Chii-Ming
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/71184192410943119591

碩士 === 淡江大學 === 土木工程學系 === 85 === In recent years, large number of highrise buildings are built due to the rapid economic development and highly use of land. At the same time, more complex structure system design causes eccentricity which also change many building behavors. Amongthem, special aeroelastic phenomenon would be handled and solved by method of wind engineering. The purpose of this article is to apply a building model which includes alongwind, acrosswind and torsional motion under the wind tunnel test to investigate the aeroelastic behavior of shape a square highrise building in different flow fields. Damping rations, torsional / lateral frequency ratio and eccentricity are used as the experimental parameters. According to the experimental result, the acrosswind dynamic responses show peak values at critical velocity when building has eccentricity in the acrosswind axis in BL1 flow field. The peak values amplified with the increase of eccentricity, but reduced as the frequency ratio close to 1.0. In BL2 flow field, the aeroelastic effect weakened due to presence of the stronger tubulence. Hence, the acrosswind dynamic responses do not have peak near critical velocity as in BL1. When eccentricity increases, as thstiffness center moves down wind of geometry center, building''s dynamic respones increase especially near critical velocity. When the torsional / lateral frequency ratio approache unity, responses will further increase. In the aspects of acrosswind vibration and vortes shedding, we find that the strenght of vortex and the lock-in phenomenon is also more apparent will increase with increase eccentricity. Moreover, when the stiffness center towards down wind and the frequency ratio approache 1.1, the increase of vortex strength becomes more obvious.