Analysis Of Temperature Effect On Kiewitt Spherical Reticulated Mega-structure

Building structures have temperature effect generally under the change of seasons,spring summer, autumn and winter. People must consider indoor heating, refrigeration and thermal insulation roofing during winter and summer, as building is normally used.We can not ignore the temperature effect during the structure design, because structure must satisfy the use requirement, and structure forms are more and more complex with structure span’s enlargement. At present, research on temperature effect of steel structure focused on traditional structure forms, such as truss, single-layer reticulated shell and double-layer reticulated shell. However, few experts do research on a new structure form – a giant grid structure. It is popular for experts with general mechanical properties of the giant grid structures at home and abroad, while they study on the temperature effect of giant grid structure rarely. The paper researches on static behavior, stable performance and dynamic characteristics of Kiewitt Spherical Reticulated Mega-structure amid the action of temperature effect.Combined with commonly used load combination conditions in design, and selecting eight load conditions of bearing capacity limit state and load conditions of normal use limit state, we consider the geometric nonlinearity of structure and use ANSYS, an large general finite element software, to calculate the stress and displacement of the main bar and main nodes. We analyze the law of stress and displacement of main bar under the temperature effect, as it is on the condition of bearing capacity limit state and serviceability limit state. We study on the temperature effect amid different temperature values, rise-span ratio, span, supporting ways. We also analyze temperature effect on master-slave structures’ coordination bearing.We make most of arc method and “consistent defect modal method” to describe the stability of giant grid structure under the condition of different or same temperature inside and outside structure. Respectively, we introduce temperature effect, the geometric nonlinearity, material nonlinearity and their coupling effect on structure to analyze stability. We deduce an free vibration equation under the temperature: [ ]{ } [ ] { } { }UKUM=+0T&&. And we use the subspace iteration method to study the dynamic characteristics of structure with same or different temperature,when the master structure undergoes singly load and master-slave structure coordinately bear the load.According to the finite element analysis, we summed up that temperature have effect on the eigenvalues of structure, elastic limit bearing capacity, elastic-plastic ultimate bearing capacity, especially it has effect on static inner force and static displacement obviously. Hence, we must put emphasis on the temperature effect analysis of static properties of structure.