This paper describes a software system named leaf for the computer-aided design (cad) of cable-stayed bridges. the leaf system performs the static analysis of three-dimensional cable-stayed bridges with nonlinear effects. also, the system performs a dynamic analysis for the extraction of pure natural modes of cable-stayed bridges under the undeformed and/or deformed service load configuration. finally, the leaf system can determine the lowest wind velocity that initiates aerodynamic flutter instability. the entire leaf system resides on an ibm or ibm-compatible microcomputing environment with user-friendly features, which include easy-to-use engineering language commands for definition of geometry, structural properties, and loading parameters, while resulting forces, moments, deflections, mode shapes, and flutter profiles can be viewed graphically with multiple-views, zooming, and animation capabilities. as a case study, the leaf system is applied to the previously built luling cable-stayed bridge. though the system's runtime is slower than mainframe-based systems, it has proved itself reliable in accuracy with the added convenience of centralized computing support for cable-stayed bridge designers. this paper appears in transportation research record no. 1290, thirdbridge engineering conference, march 10-13, 1991, denver, colorado, volume 1.
Samenvatting