عنوان مقاله [English]
These types of structures are very disposed to instability, which can limit the amount of load that can be tolerated and deformed structures, and play a fundamental role in designing structures whose loads borne by their members are mainly axial-compressive or axial-tensile. So it is important to study the stability of these structures to determine the maximum load-bearing capacity of the structure, to find the optimal geometric shape, the stiffness of the structure and collapse behavior under different loading conditions. Under different loading conditions, dome-shaped space structures exhibit various modes of instability, including member instability, nodal instability, member length instability, and general instability. Considering this type of instability, in this study, the dome-shaped space structure of the tomb of Sheikh Safi al-Din Ardabili with the special form of the dome, which has been obtained by parametric study, have been investigated. These are done by collapse analysis and the use of finite element methods. Factors such as early geometric imperfections, balanced snow load pattern in nodes, unbalanced snow load pattern in two orthogonal directions, taking into account three different height to span ratios, two lengths to width ratios of the dome and yield stress are considered In the stability behavior of the single-layer space structure of Canopy the tomb of Sheikh Safi al-Din Ardabili. The results show that the height to span ratio is an influential factor in this type of structure and with increasing this ratio, weight, the initial hardness and load capacity (for design with the same sections for all structures) increases; also the structural form of the single-layer dome-shaped space structure of the tomb of Sheikh Safi al-Din Ardabili, with its special form, is very uneconomical and inefficient, and is not recommended for structural designs and has only a beautiful aspect.