Structural analysis of loaded cable trusses

Cable trusses are far superior to ordinary roof structures of buildings made of steel or reinforced concrete. They are applicable for spans up to 60 meters or more and do not need heavy-duty installation equipment due to their low weight. On the other hand, design solutions for cable structures are hampered because software packages for the finite element analysis, are not intended for study of alternative solutions. Evaluation methods for the cable truss structure include integration of the shear force distribution in auxiliary beam and solution of a set of non-linear equations. It complicates the implementation of static analysis. The development of simplified evaluation methods suitable for general-purpose mathematical software packages, is an important task to be solved. It will enhance the quality of design solutions via specialized tools for numerical simulation and optimization. Purpose: The purpose of the work is to develop evaluation methods of cable trusses. Methodology: The proposed technique is based on the sine-series expansion of the external load and shape function of the cable truss. The assumption of small relative displacement at the center of the truss span and constant length of links between the chords yield a set of two equations. The first one is quadratic. Its solution is given in terms of the cable truss shape alteration determined from the second equation by means of the secant method. Research findings: The proposed technique allows to determine vertical displacements of the cable truss, the link load between the chords and axial forces under the external load uniformly distributed over left and right parts of the span. Nonlinear equations solved by the plane solution technique, requires much less computations in contrast to the general analysis of nonlinear systems.