Research on higher-order resonance characteristics of duct-water coupled components in rectangular aqueduct bridge

According to the operation and development of radiation therapy in the world,in order to further promote the radiation therapy of tumour in China,a design of a special synchrotron with two super-periodicity for hadron therapy is presented,including lattice,injection system,RF acceleration and slow extraction of the third order resonance.

The exploration leads to the following conclusions: with journal misalignment considered,the first-order natural frequency decreases but the second-order natural frequency increases;the amplitude of vibration for the second-order resonance is augmented;the minimum thickness of oil film is diminished whi.

The influence of higher modes on the yield displacement, ultimate displacement and the displacement ductility for a tall pier is investigated.

Since it considers the synthetic effect of the structural stiffness degradation, influence of higher modes of vibration, the spectral acceleration theory and the SRSS or CQC combination of modes, the adaptive pushover analysis is more accurate than the pattern loaded with fixed lateral force in simulating the structural stress state.

It indicates that the IASPA procedure provides more superior accuracy in estimating seismic performance structures compared with MPA procedure because it takes into consideration the contributions of higher modes to response and for the redistribution of inertia forces after structural yielding.

This paper,Zhenjiang—Yangzhou south suspension bridge as background,analyzes the effects of higher modes of vibration in calculation of suspension bridge seismic response, and provides the proper method.