Calculating the Rayleigh damping coefficient under seismic dynamic simulation of a quayside container crane

ABSTRACT

According to the Rayleigh damping coefficients based on the dynamic simulation analysis of a quayside container crane (QCC), the calculation and frequency selection for QCC type structures are improved through comparative analysis of similar models and simulation results; these models consider the boundary constraints of QCC and the calculation method of damping coefficients, but there is no consensus on the best methodology to use. The dynamic response of the QCC structure under different Rayleigh damping coefficients is compared and analysed by simulation and shaking table tests. The results show that the damping coefficient calculation method and frequency selection on the seismic response of the QCC structure increases with increased seismic acceleration. When the acceleration peak is 0.4 g and 0.62 g, the average error between the simulation result and the test value obtained by the existing damping coefficient calculation method exceeds 20%. In contrast, the error between the simulation result and the test value is within 10% when using the improved damping coefficient calculation method.

KEYWORDS:

• Simulation analysis
• damping coefficient
• quayside container crane
• seismic test
• similar model

Nomenclature

α	=	damping coefficient
β	=	damping coefficient
C	=	damping matrix
M	=	mass matrix
K	=	stiffness matrix
ζj	=	damping ratio of j mode
ωj	=	natural frequency corresponding to the j-th mode
ωε	=	dominant frequency of seismic wave
ζmin	=	calculated maximum damping ratio
ζmax	=	calculated minimum damping ratio
R1-4	=	damping coefficient obtained by calculation using method 1-4
R5	=	damping coefficient obtained by calculation using the improved method
A1-25	=	layout of measuring points on the model(1/20)
S1-16	=	layout of measuring points on the model(1/15)

Flowchart

Data Availability

The data used to support the findings of this study are included within the article.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was funded by the China National Science Foundation (Project no. 51275369).