Seismic Behavior And Failure Mechanism Of Reticulated Shells Considering The Influence Of Support Members

The reticulated shell structure has been widely used in recent yea rs due to its beautiful shapes,light weight,and excellent performance subjected to loads.However,due to the frequent occurrence of earthquakes in our country,the reticulated shell structure,which is often used as a landmark building in a region,is also facing serious threats from earthquakes.In the previous eart hquakes,many reticulated shells and grid structures have suffered severe support damage,causing the overall collapse of the structure and serious property damage,so it is of great significance to study the effects of support stiffness and support damage on the strong earthquake response of the reticulated shell structure.In this paper,the support members of single-layer latticed domes with a span of 40m?60m and 80 m were designed,and finite element modeling and analysis were performed.A simplified mechanical model of the support was extracted.On the base of that,the integrated model of the reticulated shell structure with support members is established,the influence of the stiffness of the support on the natural vibration characteristics and the strong seismic response of the reticulated shell structure was analyzed,and the reasons for the strong seismic response of the reticulated shell structure were analyzed.Secondly,a method for judging the failure of the support members based on the vertical reaction force of the support members is proposed,and the comparative study on the response of the failure of the support members to the strong earthquake of the spherical lattice shell when the support members are designed according to the rare earthquake,fortified earthquake and frequent earthquake is compared;The design of the support members according to rare earthquakes can ensure the safety and reliability of the structure under rare earthquakes and even greater earthquakes.The effects of support failure on the strong earthquake response of the reticulated shell structure under normal support variation and abnormal defects were investigated.The results show that the variation coefficient of the construction quality of the supports should be reasonably controlled and the individual supports should be avoided.Finally,the influence on the performance of integrated model of the reticulated shell structure with supports of different parameters is studied.20 earthquakes were selected to analyze the integrated model of the reticulated shell structure with supports,and the strong earthquake response analysis was performed to further verify the reliability of the support design based on rare earthquakes.At the same time,through the comparative analysis of a large number of examples,the effects of the parameters such as the span of the reticulated shell structure,the vector span ratio,and the roof mass on the strong seismic response of the overall model of the reticulated shell structure including the supports were investigated.When support failure is not considered,a spherical reticulated shell structure with small span,low rise-span ratio,and light roof mass has better seismic performance.