Study On Dynamic Property And Dynamic Responses Of Beam String Structure With Double-layer Strings

The Beam String Structure(BBS), using bar connecting arches and cables, is a new type of large-span structure. With light self-weight, strong overall rigidity upon completion and stable configuration, BBS is becoming one of the focuses for study in the field of space structure because of its successful applications in many important large-span buildings.But the function of the BSS is affected by the large sag. In my paper, a new type BSS called BSS with Double-layer Strings which dispose two layer cables on the BSS to improve the disadvantage. The work of this thesis is on the dynamic property and dynamic responses of the BSS with Double-layer Strings.Based on the FEA method for Dynamic, the motion equation for discrect structure is gotten. Based on the nonlinear analysis theory, the BSS model and the BSS with Double-layer Strings model used in the paper are builden by using the FEA program-SAP2000.In this paper two methods are adopted to analyze the dynamic property: the iterative method of sub-space and the load dependent Ritz method. The difference in the dynamic property of the two structures is gotten through comparing the analysis results of the two structures. The BSS with Double-layer Strings parameters that influence the dynamic property are particularly discussed with the load dependent Ritz method, then the influence regularity of every parameter are achieved in the paper.The BSS and BSS with Double-layer Strings'responses to uniform excitation of earthquake are analysed, the structure responses results of the two structures to the El-Centro and Taft are compared and discussed. By varying the BSS with Double-layer Strings parameters, the deformation and the internal force distribution of the dynamic responses under the EL-Centro are studied. From the obtained results, some useful conclusions for the project design are drawn.The BSS with Double-layer Strings responses under multiple support excitations which wave-passage effect are studied and compared with responses under simple support excitation. The wave-passage effect is decreased with the increase of the apparent velocity.