考虑次内力影响的贝雷梁挂篮主桁架力学状态研究  

Research on the Mechanical State of Bailey Beam Hanging Basket Main Truss Considering the Influence of Secondary Internal Force

作　　者：孙九春[1] 

机构地区：[1]腾达建设集团股份有限公司,上海200122

出　　处：《上海公路》2015年第4期23-28,8-9,共6页Shanghai Highways

摘　　要：传统的贝雷梁挂篮主桁架一般采用简化模型计算,但是该模型无法考虑次内力的影响,实践中偏于不安全。对此提出了贝雷梁次内力的产生原因,指出不同的受力模式下次内力的大小和规律有所不同。实桥分析表明,贝雷梁作为主桁架使用时局部构件的次内力远超20%,即简化梁法偏于不安全,因此对于特殊布载的贝雷梁应当采用有限元法进行分析计算。The main truss of the traditional Bailey beam hanging basket is generally calculated via the simplified model,which overlooks the influence of the secondary internal force.This would present safety concerns in practice.This article presents the causes of secondary internal force in steel trusses and points out that the level and law of secondary internal force in different models are not same.Real bridge analysis shows that the resultant secondary internal force of the local member exceeds 20%if the Bailey beam acts as the main truss,which indicates the simplified model is not viably safe.The finite element method is suggested to analyze steel truss under special loads.

关 键 词：次内力 挂篮 贝雷 桁架 

分 类 号：U445.4[建筑科学—桥梁与隧道工程]