A Cumulative Expansion Force-Finding Method for Suspension-Cable Truss Composite Structure

Suspension-cable truss composite structure is a new type of cable-strut structure which combines the conventional cable structure with the rigid truss. By laying rigid roofing slabs, this composite structure offsets most effect of the wind suction, reduces the axial force of the stable cables, and reduces the large vertical displacement effectively when compared with conventional cable trusses. For this new structure, the deformation relevance between adjacent substructures results in a nonindependent and stable union. To effectively and precisely find the cable forces of a suspension-cable truss composite structure for the construction completion state, a proper optimization order and a suitable selection of the substructures are necessary. In this paper, the structural mechanical characteristics of the suspension-cable truss composite structure are introduced at first, to reveal the force transmission path between adjacent substructures. Secondly, the cumulative expansion force-finding method (CEFM) is proposed to obtain the optimal mode of the cable force distribution with a suitable operational efficiency. A numerical example is introduced and analyzed to verify the accuracy and feasibility of this method afterwards. The results show that CEFM could find out the optimal cable force distribution of the suspension-cable truss composite structure, with a geometry shape of whole structure and a rational stress level of all the components.

DEVELOPMENT AND APPLICATION OF GLOBAL-PROCESS TENSION ANALYSIS SOFTWARE FOR SUSPEND-DOME BASED ON ANSYS

Suspend-dome includes a single-layer latticed shell and the bottom tensegrity system. The overall stress state is closely related to the construction tension process. In order to provide guidance for safe construction of suspend-dome and trouble-free operation, an iterative method to determine initial strains of the bottom tensegrity system under zero state was proposed, and software for global-process tension analysis was developed based on ANSYS. A transform interface module was developed for rapid ANSYS parametric modeling. The optimization was conducted to achieve optimal prestress. A computational module was developed for the form-finding, force-finding, and construction tension analysis. The construction process of a suspend-dome with a span of 106 m was simulated by using the construction simulation method. It was shown that the iterative tension analysis method provided accurate and reliable simulations, which could be further used to determine the prestress and form of suspend-dome. The presuppositions and obtained computation sequences of the construction simulation method agree well with the practical construction process. This construction simulation method can be utilized for construction simulation.