Research Of Vibrational Characteristics In Erect Orientation Of Dynamic Machine Foundation

The key of vibrational characteristics analysis in erect orientation of machine are establishing the model system and determining all of dynamic parameters. During several decade passed, many experimental studies and theoretical analysis have been done by many internal and external researchers on the ground stiffness of resisting pressure, the damping ratio and the vibrating mass of soil by adopting various model system. However, for the reason of different experiment situation and different analytic emphasis, the conclusions are different too. Although many countries have made their own design guideline of dynamic foundation, determining dynamic parameters still exists many problems. Therefore, it is essential that the study of dynamic foundation is continuously carried out on the base of former achievements in scientific research. In this paper, a research is carried out on the dynamic characteristics of the foundation in erect orientation of machines in detail. It can make the design of dynamic foundation become more and more perfect and reasonable.With synthesizing the relevant other internal and external researchers, the achievements of theory and the results of experiment, the follow work have been done in this project: revising the formulas of the ground stiffness of resisting pressure, the mass of vibrating soil and the dynamic affecting degree of depth, which apply the theory of elastic half-space and the knowledge of the soil dynamics and consider the influence of the soil characteristic and inertial action, the dynamic interaction between foundation and ground , the diverse load. Established the finite model of ground and foundation system with ANSYS8.0, calculated the natural frequency, made revision and adjustment to the finite model continuously in order to have it accord with the fact. Through the results of the theoretical analysis and the finite element calculation, summed-up some regulars of the ground stiffness of resisting pressure.In this paper, the formulas of the ground stiffness of resisting pressure, the mass of vibrating soil and the dynamic affecting degree of depth could provide good method to determine the dynamic parameters, which can reflect the influence of many factors such as the property of soil, the base area of foundation, the pressure of foundation, the exciting...