Sensitivity Analysis of Rayleigh Damping in Nonlinear Time-History Analysis of Tall Buildings

Amount of damping is one of the parameters that has a significant effect on results of time-history analysis of tall buildings. Most common approach for considering damping matrix is using Rayleigh damping. However, there is no consensus on how to construct this matrix. Using initial or tangent stiffness matrix for construction of damping matrix can produce different level of damping. Use of mass matrix can overestimate damping forces. In this paper, a series of sensitivity analyses is conducted on damping prior to performing the main time-history analysis to prevent overestimation or underestimation of damping forces. Different approaches have been applied to a 42-story building in the OpenSees environment and the sensitivity of the results to different amounts of damping has been analyzed. Results show that construction of damping matrix using proposed approach can satisfy both guideline standards and convergence of the nonlinear time-history analysis

Keywords:

Sensitivity Analysis , Rayleigh Damping , Tall Building , Amount of Damping , Nonlinear Time-History Analysis