Abstract
Following two kinds of analysis are essential to establish a theoretical erection system of cable net structures; 1) analysis for obtaining the normal ercetion state defined by excluding all imaginable errors arising in erection process 2) analysis for eliminating actual errors which deviate from this normal state. First of all, this paper presents the analytical method for calculating the normal erection state. Concretely, the cable tensions to be prestressed are selected as the main control parameter and these cable tensions are calculated successively according to the sequence of placing cables. In this analysis the unstrained length of cables or members is considered to be the known parameter and the geometrical shape of net surface and tension distribution are obtained from equilibrium equations at free nodes and compatibility equations of cables length. Furthermore, not only the usual analysis of clamped nodes type where the cables intersections are clamped but also the analysis of sliding nodes type where the cables intersections are able to slip against each other are developed in this paper. These two types of analysis are illustrated and compared by the example of H.P. type cable net structures. Finally, from this analysis we can certify a safety of erection procedure and specify a sequence of placing cables to avoid overstressing the supporting structures.
