Dynamic Response Analysis And Study On The Seismic Characteristics Of The Bidirectional Beam String Structure

Beam String Structure (BSS), composed of cable, rigid beam and struts, is a global structure by the pre-stress on the cable. BSS has been widely used in many large-span space structures due to its many merits such as light weight, stiffness of the system, upstanding stability of configuration and shape and applicability of architecture etc. Nowadays BSS is a focus topic in the field of the spatial structure, and what's more, this type structure has been applied successfully in many long span buildings. In this paper, anti-seismic performance of bidirectional BSS is studied based on achievement of previous research.Making use of the APDL (ANSYS Parametric Design Language) in ANSYS, developing the special parametric program to model bidirectional BSS building, which provides a precondition for the progressive study on the dynamic response and the anti-seismic performance of the structure.The finite element model of the structure, which is founded by reasonable simplification and aided by the software-ANSYS, forms a precondition of dynamics analysis, free vibration behaviors of bidirectional BSS can be obtained based on such FEM model.Corresponding dynamics equations are used to describe the dynamic behaviors of bidirectional BSS, and appropriate method to solve these problems is selected on the base of previous achievement.The anti-seismic performance of bidirectional BSS is studied systemically. The time history analysis is used to calculate and analyze the seismic response of bidirectional BSS, and the results are summarized. Furthermore, the time history analysis is adopted to calculate the response of bidirectional BSS under horizontal seismic action, vertical seismic action and there-dimension seismic action and compare the results of the three cases, Dynamics responses and geometric nonlinear dynamic behavior of long span bidirectional BSS under uniform excitation of seismic were discussed. Meanwhile, nonlinear dynamics response of long span bidirectional BSS is also discussed when suffers three-dimension seismic action. Respective effect of influencing parameters on the dynamic characteristics and nonlinear seismic response of the structure are analyzed and compared with each other, which are the rise-span ratio, the sag-span ratio, the prestress' value of cable and variational supporting conditions etc., results from the analysis supplied some applicable conclusions servicing for Engineering & design.