为了研究大跨度人行悬索桥非线性静风稳定相关参数的影响规律,采用内外两重迭代数值算法对一座420 m主跨人行悬索桥,进行了结构附加风攻角、来流初始风攻角、非主梁结构风荷载、抗风缆与中央扣结构措施等影响参数分析.分析结果表明:不计结构附加风攻角会放大静风失稳临界风速,由于正负不同初始攻角下静风荷载的不同发展路径,使得正攻角会恶化静风稳定性,负攻角会提高静风稳定性;非主梁结构风荷载对静风失稳临界风速影响很小,但是抗风缆风荷载对主梁静风位移影响很大,主塔风荷载对主梁静风位移影响最小;抗风缆会改变大跨人行悬索桥的静风失稳形态和大幅提高静风稳定性,对于420 m主跨量级的人行悬索桥,仅依赖中央扣措施很难使无抗风缆设计方案获得足够的静风稳定能力.%In order to study effects of parameters on nonlinear aerostatic stability of a long-span pedestrian suspension bridge,using the double-iteration numerical algorithm,effects of parameters including structural additional wind attack angle,initial wind attack angle of incoming flow,wind loads of non-main girder structures,wind resistance cable and central buckle structure measures on nonlinear aerostatic stability for a pedestrian suspension bridge with main span of 420 m were analyzed.The analysis results showed that regardless of additional wind attack angle enlarging the critical wind speed of aerostatic instability,different development paths of aerostatic loads under different positive and negative initial attack angles make the positive attack angle worsen the aerostatic stability and the negative attack angle improve the aerostatic stability;wind loads of non-main girder structure have little effect on the critical wind speed of aerostatic instability,while wind load of wind resistance cable has great effects on displacements under static wind of main girder,wind load of main tower has the least effect on displacements under static wind of main girder;wind resistance cable can change aerostatic instability status of a long-span pedestrian suspension bridge and greatly improve its aerostatic stability;for a pedestrian suspension bridge with main span of 420 m,it is difficult to only depend on central buckle structure measures for the design scheme without wind resistance cable to get sufficient aerostatic stability.
展开▼
