Structural Design And Analysis Of The Oversize Multifunctional Structure Test Loading System

In order to keep up with the development of the structure test, Beijing University of Technology has invested and developed the oversize multifunctional structure test loading system. If set up successfully, this most advanced system can be used to launch previously impossible immobile and mobile loading tests, the result of which can directly be applied to actual structural design. As a result, the loading system is of important significance to the design of the momentous buildings, especially constructions of 2008 Olympic Game and all kinds of new-style constructions. The paper described the structural design of the loading system in brief. The innovation of the design was that, it had used the multi-key-teeth vertical bearing framework on the loading system for the first time, and it also assembled the side-force elimination bridge and the multi-key-teeth bearing framework. So it can move up and down and counteract the side-force at the same time. As a result, many kinds of immobile and mobile tests, which previously should be carried on separately, can be executed on one machine. The thesis is mainly devoted to prove the validity of the design by analyzing the structure of the loading system, via FEA analysis software ANSYS8.0. The result of the static analysis indicated that, when the load reached the ultimate value, the stress convergence would occur in the upper beam's restricted nodes and the load location of the system of key-teeth orientation trough and orientation orbit, so the regions were very dangerous. If we analyzed again thinking of the plasticity of the material, the convergence stress decreased rapidly, and it could meet the request. The most equivalent stress of the ground supporting frame and the large reaction wall under the action of the ultimate load was less than the yield strength. At the same time, the distortion of the loading system under the limit working condition meets the precision and distortion request. Thus, the conclusion can be drawn that the loading system design proposed by this thesis is strong and stiff enough to ensure safety under working condition. The result of the mode analysis indicated that, the basic frequency of every analyzing model was higher than the relevant concussion frequency of the oil crock concussion stunner, so resonance phenomenon would not occur when the loading system was working. Seeing from the vibration model chats, the whole rigidity and mass of the loading system structure had a balanced distribution, and there were not obvious unsubstantial and superfluous parts, which would be quite advantageous to the mobile capability of the system. To sum up, the loading system had rational dynamic characteristic parameters.