Based on the basic theory of mechanics,kinematic and dynamic analysis for a slider-crank mechanism with a balance mechanism is performed.The theoretical formula of the load spectrum for the interaction between the cra...Based on the basic theory of mechanics,kinematic and dynamic analysis for a slider-crank mechanism with a balance mechanism is performed.The theoretical formula of the load spectrum for the interaction between the crank shaft and the bearing seat of the upper beam is achieved by approximately simplifying the mechanical model of the crank shaft.The simulation for the load spectrum data of combined frame under the operating conditions of blanking or piling is performed using Matlab and the law of the load spectrum curves under these two conditions is analyzed.The simulation results show that under a no-load condition,the load spectrum curves of the interaction between the crank shaft and the bearing seat of the upper beam present a form of periodic sine wave and under the piling condition,the load spectrum curves of the interaction between the crank shaft and the bearing seat of the upper beam present a form of periodic pulse wave.The simulation results can provide a theoretical foundation for the load determination during the process of analyzing the dynamic characteristics on the combined frame of a closed high-speed press through the finite element method.展开更多
Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e...Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e. g. the pushover analysis）, and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.展开更多
基金The Key Technologies R& D Program of Jiangsu Province(No. BE2006036)Transformation Program of Science and Technology Achievements of Jiangsu Province (No. BA2008030)
文摘Based on the basic theory of mechanics,kinematic and dynamic analysis for a slider-crank mechanism with a balance mechanism is performed.The theoretical formula of the load spectrum for the interaction between the crank shaft and the bearing seat of the upper beam is achieved by approximately simplifying the mechanical model of the crank shaft.The simulation for the load spectrum data of combined frame under the operating conditions of blanking or piling is performed using Matlab and the law of the load spectrum curves under these two conditions is analyzed.The simulation results show that under a no-load condition,the load spectrum curves of the interaction between the crank shaft and the bearing seat of the upper beam present a form of periodic sine wave and under the piling condition,the load spectrum curves of the interaction between the crank shaft and the bearing seat of the upper beam present a form of periodic pulse wave.The simulation results can provide a theoretical foundation for the load determination during the process of analyzing the dynamic characteristics on the combined frame of a closed high-speed press through the finite element method.
基金The National Basic Research Program of China(973 Program)(No.2007CB714200)
文摘Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis （e. g. the pushover analysis）, and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.
