Nonlinear Dynamic Analysis of Multi-Sloshing Mode Tuned Liquid Sloshing Dampers Installed in Tall Buildings

This paper presents nonlinear time domain analysis and its iterative formula for a tuned-liquid sloshing damper installed on a tall slender building under strong vortex shedding excitation. A new iterative formula is derived for a nonlinear time domain analysis of a tuned liquid sloshing damper represented in the mathematical model introduced by Warnitchai, P. in 1998. For the accurate modeling of liquid (typically water) sloshing motion, the nonlinear quadratic damping force which is generated by the liquid flow through a screen is directly implemented without linearizing the term applied in previous studies. Multi-sloshing modes of the liquid are also considered for more accurate modeling. The nonlinear sloshing damper model has been analyzed coupled with tall buildings with heights of 300m and slenderness ratios exceeding 10. The effects of nonlinearity and multiple sloshing mode effects of the liquid and efficiency of the sloshing dampers for different building frequencies and surrounding conditions are investigated. Examples include: (i) time and frequency domain analysis of; (ii) linear and nonlinear; (iii) single- and multi- sloshing mode liquid dampers; (iv) coupled with tall slender building with a range of building frequencies; and (v) under strong vortex shedding and generated from a target wind load spectra based on a Japanese Building Code (AIJ). The present formula can be used to analyze and design liquid sloshing dampers without physical damper test.