Analysis Of Dynamic Characteristics Of Machine Foundation

The key of vibrational characteristics analysis of machine areestablishing the model system and determining all of dynamic parameters.During several decade passed, many experimental studies and theoreticalanalysis have been done on the ground stiffness, the damping and the vibratingmass 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 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 ground stiffness coefficient and 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 mechanics and consider the influence of the soil characteristic and inertialaction, the interaction between foundation and ground, the diverse load; making the model of ground and foundation system calculating natural frequency by using the big-scale software SuperSap which is for special purposes of finite element analysis; according to the experiment analysis, correcting and adjusting the finite element model in order to have it accord with the fact and meet the engineering demands; doing the vibrating experiment for testing the results of the theoretical analysis and the finite element calculation; summing up some regulars of the ground stiffness.In this paper, the formulas of dynamic parameters 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 frequency and so on. The method of establishing model in the finite element calculation can be used to the engineering calculation of machine foundations and carrying out the theoretical research. The regulars of ground stiffness provide the valuable reference for the design of dynamic foundation.