TY - JOUR
T1 - Extraction of Nonlinear Aerodynamic Damping of Crosswind-Excited Tall Buildings from Aeroelastic Model Tests
AU - Hao, Wei
AU - Chen, Xinzhong
AU - Yang, Qingshan
N1 - Publisher Copyright:
© 2020 American Society of Civil Engineers.
PY - 2020/3/1
Y1 - 2020/3/1
N2 - This paper presents a new approach for extracting nonlinear aerodynamic damping of crosswind-excited tall buildings from response statistics at different levels of structural damping obtained from aeroelastic model tests. The aerodynamic damping at a given wind speed was modeled as a polynomial function of the amplitude of the harmonic building motion, which leads to analytical solutions of the standard deviation (SD) and kurtosis of the crosswind response under stochastic load excitation. As an inverse problem of response analysis, the nonlinear aerodynamic damping model coefficients can be identified from known response SD and kurtosis through a nonlinear optimization algorithm. The crosswind loading spectrum at the structural frequency can be determined from rigid model testing or treated as an unknown. The accuracy of this identification scheme is first illustrated using crosswind response of a tall building calculated from a given nonlinear damping model. It is then applied to a square-shaped tall building using aeroelastic model testing data under boundary-layer flows. The limitation of the conventional approach, which did not account for the response kurtosis, is highlighted. With the proposed approach, the effect of approaching flow characteristics on crosswind aerodynamic damping is examined.
AB - This paper presents a new approach for extracting nonlinear aerodynamic damping of crosswind-excited tall buildings from response statistics at different levels of structural damping obtained from aeroelastic model tests. The aerodynamic damping at a given wind speed was modeled as a polynomial function of the amplitude of the harmonic building motion, which leads to analytical solutions of the standard deviation (SD) and kurtosis of the crosswind response under stochastic load excitation. As an inverse problem of response analysis, the nonlinear aerodynamic damping model coefficients can be identified from known response SD and kurtosis through a nonlinear optimization algorithm. The crosswind loading spectrum at the structural frequency can be determined from rigid model testing or treated as an unknown. The accuracy of this identification scheme is first illustrated using crosswind response of a tall building calculated from a given nonlinear damping model. It is then applied to a square-shaped tall building using aeroelastic model testing data under boundary-layer flows. The limitation of the conventional approach, which did not account for the response kurtosis, is highlighted. With the proposed approach, the effect of approaching flow characteristics on crosswind aerodynamic damping is examined.
KW - Aeroelastic model testing
KW - Crosswind response
KW - Nonlinear aerodynamic damping
KW - Tall buildings
KW - Vortex-induced vibration
UR - http://www.scopus.com/inward/record.url?scp=85074709909&partnerID=8YFLogxK
U2 - 10.1061/(ASCE)EM.1943-7889.0001731
DO - 10.1061/(ASCE)EM.1943-7889.0001731
M3 - Article
AN - SCOPUS:85074709909
SN - 0733-9399
VL - 146
JO - Journal of Engineering Mechanics
JF - Journal of Engineering Mechanics
IS - 3
M1 - 04020006
ER -