Researches On The Progressive Collapse Resistance Of Spoke Cfrp Layer Cable Structures

In this paper,the carbon fiber reinforced compound material is applied to the cable of spoke tension structure to form the spoke tension carbon fiber cable structures.This structure not only makes full use of the high tensile property of carbon fiber,but also reduces the self-weight of the structure.Therefore,the spoke tension carbon fiber structure will occupy a space in the future,and the current research is basically limited to much research area such as form-finding,force-finding,static analysis,seismic analysis,construction forming,etc.… and there is few research on progressive collapse resistance.In this paper,the vertical strut spoke tension structure is adjusted to form a new structure,namely the inclined strut spoke tension structure,and the progressive collapse resistance of these two structures is analyzed.The main contents of this thesis is based on the force-finding principle of dynamic relaxation method,the initial prestress of spoke tension structure is solved by Matlab,and verified by Ansys based on nonlinear finite element method（FEM）.Under the condition of the same rise-span ratio and the same cross-section size,the vertical strut spoke tension structure and the inclined strut spoke tension structure with span of 120 m are designed,and the Ansys analysis is carried out to ensure that the displacement and internal force of the cable structure agre within the limits under various working conditions.Modal analysis is carried out by Ansys,the overall performance of two spoke tension structures is explored,and parameters are extracted for dynamic analysis.Based on the alternate load path method,FEM software Ansys is used to analyze the linear static resistance to progressive collapse and Ls-dyna FEM software is used to analyze the nonlinear dynamic resistance to progressive collapse,and displacement index is used to evaluate the importance of spoke tensioned structural members and to explore the progressive collapse resistance.Comparing the difference of progressive collapse resistance between two spoke tension structures,and analyzing the difference of static and dynamic analysis is analyzed to verify whether the static analysis can guide the dynamic analysis.Under the condition of dismantling several strings of the same type,this research studies the difference of progressive collapse resistance between two spoke tension structures.Under normal design,the progressive collapse will not occur in the two spoke tension structures under static analysis and dynamic analysis.In order to clearly solve the collapse path of the structure,the progressive collapse of the structure is promoted by reducing the cross-sectional area of the structural brace,and then the structural displacement,internal force time history and collapse path are analyzed.Finally,according to the above analysis results,some design suggestions are given for the progressive collapse resistance of the two spoke tension structures studied in this research.