索穹顶主动索的张拉影响系数

TENSIONING INFLUENCE COEFFICIENT OF CABLE DOME STRUCTURES

碳纤维材料具有轻质高强、耐腐蚀及高耐久性方面的优点,碳纤维索穹顶结构可实现比钢索穹顶结构更大的跨度。索穹顶的预应力水平对结构受力和刚度的影响非常显著,因此需确保张拉完成后构件有效预应力的建立。提出了用于计算索穹顶结构主动索张拉值的张拉影响系数,分别从变形协调条件和虚功原理两个角度推导了索穹顶结构张拉影响系数的表达式,并利用碳纤维索穹顶模型试验及有限元分析对该张拉影响系数的准确性加以验证。此外,对3种张拉方案下预应力发展规律及节点的竖向位移进行了分析和探讨,进而建议了主动索的选取原则。

Carbon fiber materials have the advantages of light weight, high strength, excellent corrosion resistance and good durability. The carbon fiber reinforced polymen(CFRP) cable dome structure can achieve a long span than the steel cable dome structures do. The prestress level of a cable dome has significant influences on the structural forces and stiffness, so it is necessary to ensure the effective prestress of the members after the tensioning is completed. In this paper, the tensioning influence coefficient of cable dome structures for calculating the tensioning value of active cables was proposed. Based on deformation coordination conditions and the principle of virtual work, the expression of the tensioning influence coefficient of the cable dome structures was derived, and the accuracy of the tensioning influence coefficient was verified by the model test of CFRP cable dome and finite element analysis. In addition, the development law of prestress and vertical displacement of connections under three tensioning schemes were analyzed and discussed, and the selection principle of active cables was proposed.