Tensile Structures of Cables Net, Guidelines to Design and Applications

Abstract

The structural engineering design of not conventional typologies imposes a complex path that begins evaluating procedures of a preliminary design and ends with complex procedures to validate the analysis response. Any guide lines to follow are often available. About complex shapes, in particular, any details are presented in the codes to evaluate wind action and so wind tunnel experiments are necessary to valuate this. The evaluation of wind tunnel data is a complex process that often needs new and specific subroutines programmed by researchers. The difficult increases when the objective is to study a not specific building but general aspects as for examples the dependence of a generic phenomenon by a geometric sample; in this case it is necessary to design and to program numerical subroutines before and then the wind tunnel experiments. Often, these subroutines are left detached and are non-generalizable process. Purpose of this paper is to describe a complete procedure to pre-and post-process wind tunnel data with the objective to design a not convectional structure as a tensile structure. In this particular case the research aim is a parametrization of the aerodynamic behavior of Hyperbolic Paraboloid roofs, shape used for cables net. The reason of the experiments is the absence in the international codes of the pressure coefficients for these geometries. The paper describes the numerical procedure evaluated to choose a sufficient representative geometric sample, the numerical procedure evaluated to design and to construct the wind tunnel models and FE models, the numerical procedure to evaluate and to use for FEM analyses of the wind tunnel data, the numerical procedure to calculate nonlinear structural analysis, and, finally some applications. All these numerical procedures use basic theory derived for example by the cable theory, the fluid mechanic, the nonlinear geometric analysis and other. However specific codes were necessary and were programmed to apply the theories on the specific case of study; the complete methodology followed is presented. The goal is to create a free open domain where the numerical procedures evaluated are merged, added, modified by researchers with the aim to obtain a common space of use for wind engineering of not conventional structure.

Hemp Cables, a Sustainable Alternative to Harmonic Steel for Cable Nets

“…Static and modal analyses are carried out by TENSO (2011), a non-commercial software that includes modules for simulating cable and beam finite element models, and for the study of wind-structure interaction phenomena with the generation of wind speed time histories and simulation of various aeroelastic loads. The main cables are discretized as rectilinear cable segments [15,16,59]. The global stiffness matrix is updated at each load step by assembling the stiffness submatrices of the elements, and updated so as to account for the strain found at the previous time step.…”

“…The geometry is given by Equation (1). In this study, parameter c is equal to 1. In Equation (1), x, y, and z are the spatial variables; x 0 , y 0 , and z 0 are the coordinates of the origin of the axes; and a, b, and c are the geometric coefficients of the function [31,59].…”