大跨径缆索承重桥梁非线性空气静力稳定理论

NONLINEAR AEROSTATIC STABILITY THOERY OF LARGE-SPAN CABLE-STAYED BRIDGES

汕头海湾二桥模型在风洞试验过程中意外的发生了静风失稳现象。为了彻底探明这一现象，首次提出了非线性空气静力稳定理论。通过运用所编制的程序对这一实例展开深入、全面的力学分析，获得了与试验极为接近的力学行为及临界风速值，并探明了失稳的力学机理，从而初步证明这一理论的适用性及程序的正确性。

During the wind-tunnel model testing of the second Shantou bay bridge, an aemetatic instability phenomena has appeared unexpectedly. In oaler to probe the phenomena, nonlinear aemetatics stability theory has been developed for the first time.The theory is estabished from three ways. Firsdy, nonlinear calculating method of aerostatic loads is presented, in which the aerostatic loads are described as the functions of structural deformation with nonlinear dects of aerostatic loads considered.Secondly, combining the method with spatial stability theory of large-span bridges, the theory is constituted. Thirdly, corresponding analysis procedure system is developed. By applving the procedure spstem, the phenomena is analytal. Some important conclusions are obtained, which are in accordance with the results of wind-tunnel test. Therefore, the theory and system preseted in the study has been prelimineq verified.