Evaluation of behaviour of hybrid composite cable in the saddle-shaped roof

摘要

Hybrid composite cable with increased, in comparison with CFCC, breaking elongation and decreased, in comparison with the steel cables, dead weight could be elaborated for prestressed cable net on the base of carbon and steel. Hybrid composite cable contains three layers: carbon fiber reinforced plastic (CFRP) core, glass fiber reinforced plastic (GFRP) distributional layer and steel wire strands. All layers of hybrid composite cable take up tension stresses, acting in the cable during exploitation. But GFRP has second function - distribution of transversal pressure of steel wire strands at CFRP core. The dependence of external pressure per unit of the surface area of the GFRP (due to the pressure of steel wire strands) of hybrid composite cable on the axial force and angle of steel wire strands twisting was estimated by the engineering method of calculations. Tangential and radial stresses for GFRP and CFRP components of hybrid composite cable were obtained. It was shown, that the angle of steel wire strands twisting should not exceed 20 degrees due to the ultimate strengths of GFRP and CFRP components in radial and tangential directions. Opportunity to decrease the displacements of composite saddle-shaped cable roof by the using of cable trusses made of hybrid composite cable, as a supporting contour structure, was investigated.