Study On The Mechanism Of Continuous Collapse Failure Of Large-span Prestressed Steel Reticulated Shells

In this paper, Qingyuan City, Guangdong Stadium as the research object, the structure in the form of large-span prestressed composite Torsional Reticulated Shell, buckling analysis in considering its eigenvalues traditional circular steel compressive stress-strain constitutive relation under the condition of dual nonlinear analysis and dynamic analysis to study the mechanism of collapse. For more in-depth study of the collapse of its performance, this paper introduces the consideration of axial compressive ultimate bearing capacity of circular steel constitutive relations, in order to carry out further structural progressive collapse analysis, and the model and the traditional constitutive relations for comparison. On this basis, this paper introduces the sleeve member, the sleeve member analysis for large span prestressed composite Torsional Reticulated Shell collapse control effect. The main conclusions are:Chord member(1) the structure of, and sensitivity values oblique webs pole higher and lower sensitivity values lower chord, the results of sensitivity values calculated Tendons small, but it is a very important component, so Key Analysis;(2) Without considering the destruction of the pillars of the premise, consider the traditional model and the constitutive relationship model to consider axial compressive ultimate bearing capacity of circular steel tube removal the same single prestressed cable progressive collapse occurs, but overall damage than the latter the former is larger, the latter model that is more realistic strut member is provided, so the study of the structure of prestressed cable damage, the latter would be more reasonable;(3) removal of the center of the grid winding a twisted network nodes and monolithic shell center four nodes, taking into account traditional constitutive relation and axial compressive ultimate bearing capacity of circular steel constitutive relation, the structure does not appear plastic hinges it does not suffer the stress ratio overrun lever, the structure will not collapse;(4) removal of nodes near the seat 5, constitutive relationship model considering axial compressive ultimate bearing capacity of circular steel tubes under each twist in the final collapse of the network will appear shell plastic hinge, wherein removal of the nodes where the network shell plastic hinges develop more serious, three lighting connected with the most serious. Constitutive relationship and consider the traditional model comparison, the structure will appear progressive collapse, but the collapse of the former longer than the latter about early 1s, and at the same time, the former more serious damage, so the collapse of the former research when more reasonable and important;(5) arranged in the casing of the number of different models lossy seat 5 near the removal of nodes, with the increase in number of the sleeve is arranged, the vertex displacements and the displacement of the failed node structure becomes progressively decreases, at the same time have a development of the plastic hinge structural damage along with the number of casing near the failed node increases. But when at the bar mounts failure, use the sleeve member is difficult to control their collapse does not occur, so at the support and the stand near the bars is the overall structure of the most critical positions, both in the design and construction process, We should pay attention to.