Research On Cable Corrosion And Its Performance Degradation Of Cable And Suspendome Structure

The development of society is inseparable from the promotion of people’s needs.People’s demand for large span and large space promotes the breakthrough of building structure to a larger span.The suspendome structure can achieve a breakthrough in structural span by introducing prestress into the lower cable support system.At the same time,it will be widely used in various important public buildings in the future by virtue of its beautiful structural shape.As the prestressed ground carrier in the suspendome structure,the cable plays a decisive role in the structural performance.However,the cable will inevitably suffer environmental corrosion in the service process,resulting in the degradation of the mechanical properties of the cable,thus affecting the static performance of the structure and threatening the structural safety.In this paper,the commonly used cable-1 × 7 steel strand in buildings is taken as the research object.In view of the cable corrosion and the degradation of the mechanical properties of the cable and the suspend-dome structure caused by the cable corrosion,the combination of experimental research and numerical simulation is used to study the corrosion mechanism of the cable and the degradation of the mechanical properties of the cable caused by the cable corrosion,and the influence of different corrosion conditions of the ring cable on the static performance of the suspendome structure is analyzed and studied.The main research work of this paper is as follows.(1)According to the mechanism of metal corrosion,COMSOL Multiphysics is used for numerical simulation to qualitatively predict the corrosion of steel wires in the cross section of steel strands,which provides a method for predicting the corrosion deformation of steel strand cables.(2)The accelerated corrosion test of the cable was carried out.The corrosion mechanism of the steel strand was analyzed by the test corrosion phenomenon,and the correctness and feasibility of the corrosion simulation method of the steel strand cross section steel wire were verified.The equivalent relationship between accelerated corrosion environment and swimming pool environment is established to realize the corresponding relationship between accelerated corrosion test and real corrosion of swimming pool environment.(3)Corrosion rate statistical analysis of the corroded strand,fitting out the solution PH,Cl~- concentration,corrosion time T and corrosion rate η relationship formula,combined with accelerated corrosion environment and the equivalent relationship between the swimming pool environment,to provide a method for predicting the degree of corrosion of the real swimming pool environment cables.(4)Through the research on the static tensile test of corroded steel strands and the fine simulation of corroded steel strands,the numerical model of the constitutive relationship of steel strands is established to reveal the influence of corrosion on the degradation of mechanical properties of steel strands.(5)The effects of four kinds of corrosion conditions of ring cables on ring cable prestress,shell deformation and axial force of shell members of suspendome structure are analyzed to reveal the degradation law of cable corrosion on static performance of suspendome structure.