虑纵向加劲肋影响的曲线钢箱梁剪力滞效应  

The effect of shear lag considering longitudinal stiffeners of curve steel box girder

作　　者：李陇亮 LI Longliang(China Railway SIYUAN Survey and Design Group Co.,Ltd,Wuhan 430063)

机构地区：[1]中铁第四勘察设计院集团有限公司交通院,武汉430073

出　　处：《铁道勘测与设计》2021年第4期40-43,共4页Railway Survey and Design

摘　　要：与混凝土箱梁相比较,曲线钢箱梁除了具有更加明显的薄壁特征外,由于初曲率的影响和构造细节的不同,如截面设置有纵横向的加劲肋及横隔板,使其剪力滞分布与混凝土箱梁相比有所不同。本文以曲线钢箱梁为研究对象,利用ANSYS有限元软件,分析了曲线钢箱梁在设置纵向加劲肋构造前后截面的应力分布规律及剪力滞分布规律。在剪力滞系数计算时,综合考虑了薄壁结构发生的弯曲、扭转、剪力滞和畸变等变形产生的截面实际应力,与材料力学原理计算的弯曲应力作比较,得到广义的剪力滞系数。通过本文算例可知,当设置纵向加劲肋构造时,曲线钢箱梁截面顶、底板应力可降低12%与8%;对于顶、底板剪力滞系数,利用本文方法计算的广义剪力滞系数呈增大趋势。Compared with concrete box girder,curved steel box girder has more obvious thin-walled characteristics.Due to the influence of initial curvature and different structural details,such as longitudinal or transverse stiffeners and transverse diaphragms,the shear lag distribution of curved steel box girder is different from that of concrete box girder.Taking the curved steel box girder as the research object,this paper analyzes the stress distribution law and shear lag distribution law of the curved steel box girder before and after setting the longitudinal stiffener by using ANSYS finite element software.In the calculation of shear lag coefficient,the actual stress of thin-walled structure caused by bending,torsion,shear lag and distortion is comprehensively considered.Compared with the bending stress calculated by the principle of material mechanics,the generalized shear lag coefficient is obtained.The calculation example shows that when the longitudinal stiffener is set,the stress of the top and bottom plates of the curved steel box girder section can be reduced by 12%and 8%;for the shear lag coefficient of the top and bottom plates,the generalized shear lag coefficient calculated by this method is increasing.

关 键 词：曲线钢箱梁 纵向加劲肋 剪力滞效应 ANSYS 

分 类 号：TU3[建筑科学—结构工程]