Mechanical Performance Research Of Beam String Structure And Program Development

As a new type of space structure, the concept of Beam String Structure(BSS) was proposed by Japanese Professor M.Saitoh in early eighties. It's a kind of self-balance system linking anti-bend component and anti-haul component with struts, inflicting pre-stress on the anti-haul component to reduce the burden of anti-bend component. This type of structure possesses synthetically the characteristic of high anti-bend rigidity and high anti-haul rigidity, can make up each other's disadvantage of rigidity component and flexible component. The system has lower weight, high rigidity and high stability of shape, can span large space. It has been developed and applied rapidly in the recently ten years and has wide prospect.Generally the space BSS is laid by several plane Beam String Structures vertically and horizontally. It's necessary to research plane BSS which's mechanics performance has significant effect on space BSS.With the basic of existed research documentations on BSS, this paper developed correlative computer analysis program on plane BSS by the finite element method and Visual C++6.0.The geometry nonlinear problem of BSS has been considered and the program treats with beam or arch as space beam element, struts as pole element, tightwire as cable element, deals with computation with increment iterative method, can apply the whole process analysis of load-displacement curve. It can analyze the mechanics performance of BSS in the hauling period and the application period with well interface and interactive operation. The precision of computation has been proved by the comparison with example of documentary experiment data, which can meet the needs of engineer design and computation.With the assistance of the program, the paper has analyzed the mechanics characteristics of plane BSS in detail. The effects on structure from the number of struts, sag-span ratio, rise-span ratio, pre-stress of string, etc has been studied. It is helpful to realize BSS and provides reference for design and construction.