Dynamic Response Analysis For Frame Structures Under The Excitation Of Pulse-like Ground Motion And Its Components

Under the effect of rupture directivity and other factors, there is often a kind of special ground motion in the fault zone which is characterized by obvious high velocity,high displacement amplitude and long period.In studys, this kind of earthquake is often called near-fault pulse-like ground motion.The study shows that the structures need higher ductility and strength requirement under the near-fault pulse-like ground motion. Researchers have generally agreed that the influence of this kind of ground motion to seismic design in the fault zone should be considered. For further investigating the failure mechanism of building structures under the excittion of pulse-like ground motions, this article adopts wavelet analysis to extract the velocity pulse of pulse-like ground motion and uses multi-scale decomposition method to obtain the ground motion components with different frequencies. The dynamic response analyses of different layers and differnet ductility level of the reinforced concrete frame structure under the excittion of pulse-like ground motion and its components are presented in this article. The researche work of this article is hopted provide valuable reference about building structure seismic design in the fault zone and earthquake reinforcement. The research of this paper includes the following aspects:(1) Firstly,Built 4 kinds(1 layer, 2 layers, layer 4 and 8 layers) of reinforced concrete frame structure that could meet China’s current relevant specification in PKPM.then according to the detailed parameters in PKPM, respectively established four frame structure with different layers of two-dimensional analysis model in the Open SEES. Based on the previous analysis, this paper selected 65 typical pulse-like ground motion from the 17 earthquake.(2) The typical velocity pulse is the main characteristic of near-fault pulse-like ground motion which is different from common ground motion. For quantitative analysis of velocity pulse effect of the frame structure, In this paper, the wavelet analysis is used to separate the velocity pulse in the pulse-like ground motion.and then the comparative analysis the dynamic response of frame structure in original vibration, velocity pulse and the resid part. Discuss and analysis the regularity of the acceleration response, speed response, displacement response, the interlayer displacement angle and the position of weak layer of 4 frame structure with ground motion parameters,pulse parameters.(3) The visible light consists of a series of light waves of different frequencies, and the ground motion is composed of a series of components of different frequencies. For systematically discuss the effscts of different frequencies of ground motion component to the frame structure, and try to explore a method from the component to analysis dynamic response of frame structure in ground motion component, this paper use the multiscale decomposition method to decompose each pulse-like ground motion into ten different frequency motion component and exploring dynamic response parameters of the structure in original motion and vibration component.