Research On Performance Evaluation Index Of Large-span Prestressed Steel Reticulated Shell Structure Against Collapse

Based on the structure form of long-span prestressed double layer composite torsional reticulated shell of qingyuan city,guangdong province stadium as the research object,the sensitivity zone demolition nodes for research,a total of demolition of node model has 28,including demolition of 2 nodes,three nodes,four nodes,nodes five,six,seven and eight nodes,and introduces the remaining after the demolition of node force of the structure of the loading way.Combine both energy and displacement,and put forward the double parameter dynamic failure criterion,using structural dynamic damage index D value measure the extent of damage of structure.The main research conclusions are as follows:(1)In SAP2000,the structure of plastic accumulated energy dissipation calculation are introduced.Lists five demolition of different node number of model,to illustrate the plastic accumulated energy dissipation and the D value calculation process.28 model will be the final list calculation results are analyzed,it can be seen in dynamic damage index D values to reflect the degree of structural damage more accurately.Will damage the hierarchy of the structure,respectively as the basic sound,slightly damaged,moderate damage,severe damage and collapsed five grades,and use dynamic damage index D values as control index.Finally,in accordance with the control index to 28 D value model of damage were divided.(2)In the event of a continuous damage model(20)and collapse occurred secondary damage model(19)of the plastic hinge position and displacement of the first big and maximize the bar stress arrangement to study the structure of the collapsed casing components,the results show that the casing is decorated in maximize mechanical components effect is much better than any other position,including when model(20)in the two bars of the largest stress component 6 and 7 decorates two joints of casing,the dynamic damage index D value reduced by adding casing component before 20.0383 to 0.3294,the destruction of the structure control within the scope of the slight damage;When the model(19)in the two bars of the largest stress component 5 and 6 decorates two joints of casing,the dynamic damage index D value reduced by adding casing component before 1.6874 to 0.3679,the destruction of the structure control within the scope of the slight damage,with the D value to judge the structural damage is more convenient and reasonable.It is concluded that casing components should decorate the position of the largest stress in the structure.