Vibration Examination And Finite Element Analysis Of Great Machine Foundation

According to the vibration of roller mill foundation in concrete production, the subject of finite element simulation to large-scale dynamical foundations is put forward. This paper is composed of three parts, first part introduce two kinds of dynamic constitutive model of the soil below foundation, describe the H-D pattern calculation. It also introduce current theory method of quality-damp-spring model calculation, and research elastic semi-space method which is relatively more precise, create wave equation, analysis the influence of embedding effect in the same time. The second one is the extraction of dynamic load, namely, define the time history of dynamic load applied on foundation. The third one is the finite element simulation of dynamic foundation, considering the interaction, make it reflect the performance of foundation soil such as rigid coefficient, damp and so on. Optimizing the existing finite element model for economic and reasonableThis paper discussed the theory that exist now , including fluctuate theory, soil dynamics, research of elasticity half space laws and dynamic base foundations etc. and made the carefiil contrast to them. Make the test on the machine foundation, put the sensors at the control points and then obtain the acceleration time history curve. Filtrate the high frequencies and got the displacement time history curve of control point by conversion, apply them as force of the structure. The dealing of the interaction of the soil and foundation, the paper made a lot of work on it. This finite element models adopt ground soil spring to imitate, applying the elastic coefficient and damping coefficient to the springs, the coefficient is concluded from the characteristic of the natural soil, the foundation is imitated by solid element, NO. of the nodes contact are merged. The author write two element analysis program considering two kinds of boundary , introduced how to imitate and predigest. And in the same time, utilize optimization tools and regard volume of the foundation as goal function, then optimize the size of every part of the foundation , it is proved reasonable by reality.Analysis the test result, finite element simulation, and the theory calculation , the program can imitate the interaction between the soil and foundation. It also can be used as design reference on different scale and conditions of soil.