Research and practice on passive tensioning technology of cable-stayed reticulated structure

Abstract

Cable force of pre-tensioned cables decreased as subsequent cables were tensioned during construction of cable-stayed reticulated structures. Reasonable construction method must be drawn up to ensure accuracy of cable force, reduce construction input and accelerate construction progress. Two methods of positive sequence analysis and inverse sequence analysis for tension construction of cable were summarized and corresponding finite element analysis flow charts were developed. It is pointed out that cable tension force can be achieved only by one-step tensioning in batches according to analysis of inverse sequence method. The passive tension method of cable was put forward and was suitable for cable-stayed reticulated structure whose mast can rotate freely around the bottom joint. Based on characteristic of this type structure, cable force can be realized by method of one-step tensioning in batches. Inverse sequence method should be adopted to analyze construction process of cable. By analysis of inverse sequence method, the passive tension method based on non-stress cable length is studied. Engineering practice proved the passive tension method of cable can precisely control cable force after correct inverse sequence analysis and equipments were further reduced.