سال انتشار: ۱۳۸۲

محل انتشار: ششمین کنفرانس بین المللی مهندسی عمران

تعداد صفحات: ۸

نویسنده(ها):

S.A.Sadrnejad – Associate Prof., Civil Engineering Dept., K.N.Toosi University of Technology, Teheran, Iran

چکیده:

A finite element solution based on equevalent elements is proposed for the static and dynamic analysis of tall high tensioned cable antennas. To reduce high number of degrees of freedom in space frame body of a structure, an equivalent single beam element is defined for each simulative substructure. This numerical procedure is applicable to analyze complex three dimensional assemblies of substructures of similar complex structures. In this analysis wind pressure effects accompanied by change of postentioning loads in nonlinear cable elements, earthquake effects,and any other arbitrary loads on the substructures. Accordingly, the restriction of the loads on the cable elements to gravity and thermal loads can be applied.The algorithm is developed upon an efficient cable elements depending on the given position and curved geometry of the cable, its end forces, and its tangent stiffness matrix.The employed formulation scheme permits any magnitude of deformation for straight or curved elements. The postensioning stresses in cables were considered as initial stresses.To simulate the equevalent elements, both ends stiffness components are calibrated to present the same responses as the selected substructure. To simulate dynamic responses,the equevalent mass and its adjusted position are carried out to obtain the same frequencies in equevalent elements