The Design and Analysis of Alternative Defensive Ability for Cable-membrane Roof Structure of Shenzhen Baoan Stadium

摘要

The wheel-spoke cable-membrane system which spans 245 meters is adopted in the roof steel structure of Shenzhen Baoan stadium. Cable-trusses are the basic elements in this system. However,cables and membranes are all flexible components,so the shape and stiffness of the system completely depend on the value and distribution of pre-stress in those components. From viewpoint of security, when some cables are broken accidentally by abnormal loads,the re maining structural elements will redistribute stresses. In order to investigate the influence of the broken elements on the whole structure,it is necessary to analyze the behavior of the remaining structure when some cables are broken and evaluate the safety of remaining structure. In this paper, based on the theory of progressive collapse,"unlock buttoned" effect is proposed firstly. The assessment principles which are matching for the analysis of cable-broken are listed as followed. Then the concept of initial failure elements and judgment load combinations is conceived ac cording to these principles,which provides an effective measure to evaluate the safety performance for such struc tural system. As a case study, the roof steel structure of Shenzhen Baoan stadium is deeply analyzed. According to its results, this structural system has a good performance of alternative defensive ability. Finally,some helpful con clusions which can be referred by similar engineering are drawn.