关于桥梁结构线弹性稳定安全系数的讨论

针对桥梁工程中关于结构线弹性整体稳定安全系数的计算方法存在争议并给桥梁设计及计算带来不便的情况,对现存的三种常用方法进行了阐述,提出了线弹性分析时应注意的三个观点;以一下端固结柱为例,对三种不同的线弹性稳定安全系数计算方法进行分析对比,提出了一种新的计算方法--改进的线弹性稳定安全系数计算方法,并结合某钢管混凝土劲性骨架拱桥对各不同计算方法进行分析.结果表明:针对如今线弹性稳定安全系数计算方法的不足,新方法对承重结构恒载与外荷载进行区分,首先计算结构在恒载作用下的稳定安全系数,然后在确保结构满足自身最低稳定要求的前提下计算结构在外荷载作用下的稳定安全系数.改进的线弹性稳定安全系数计算方法能较合理的判断结构的线弹性稳定性及承载能力,而且专业概念明确,可供工程设计人员参考.

A discussion on linear elastic stability safety coefficient of bridge structure

There are disputes in the calculation of elastic stability coefficient in bridge engineering, which brings inconvenience to the design and calculation of bridges. In view of that, three common methods about it were expatiated, and three opinions that should be paid attention to in elastic sta-bility analysis were presented. Taking a bottom consolidated pillar as example, the elastic stability coefficients given by the common methods were analyzed and compared and a new ameliorated calcu-lation method was proposed. The methods had been analyzed and compared in detail after being ap-plied to a concrete-filled in steel tubes(CFST) stiff-skeleton arch bridge. The results showed that the new method firstly calculated the stability coefficient of structure under the action of dead loads, and then, on the Premise that the stability of the structure subjected to dead loads satisfing the low-est requirement, the stability safety coefficient of external loads was calculated. With this new meth-od the elastic stability and beating capacity of structure can be estimated more reasonably, providing a reference to engineering designers.