索穹顶比值逆迭代法形态分析OACSTPCD

The geometric shape of cable dome structure is closely related to the distribution of prestress,and the prestress proportional relationship between cable and strut is unique under the same geometric shape of the structure.Based on this,a new form analysis method,ratio inverse iterative method,is proposed in this paper,which can simultaneously obtain the axial force distribution of cable-strut in the pre-stress state of the structure and geometric coordinates of balanced pre-stress state.It can change the structural geometry in the iterative process to make the internal force distribution more uniform.Firstly,the form analysis of Gieger cable dome is used to verify the correctness of the ratio inverse iteration method.The results show that the ratio inverse iterative method has high efficiency,gives reasonable distribution of internal forces of cable and strut,and generates small configuration deviation between the balanced pre-stress geometry and the design pre-stress geometry.Secondly,on the basis of calculation example verification,the coordinates of the lower nodes of the strut are adjusted according to node displacement in the iterative process of ratio inverse iteration method.The structural geometry of the original example model is changed to make the internal force distribution of the improved model more uniform.The results show that,compared with the original model,the internal force distribution of the improved model is more uniform,and the obtained balanced pre-stress geometry meets the precision requirements.The algorithm is suitable for the form-finding analysis of cable dome structure,and the internal force distribution of cable and strut is optimized,which provides a new idea for the analysis and design of cable dome structure.