Decoupling solution to shear lag effect on box girder

作者：Yang Lufeng^*; Zeng Youfeng; Zhou Yuee

来源：China Railway Science, 2014, 35(1): 21-27.

DOI：10.3969/j.issn.1001-4632.2014.01.04

• Box girder
• Closed form solutions
• Governing differential equations
• Longitudinal displacements
• Shear lag effects
• Total potential energy
• Variational principles
• Various boundary conditions

In order to solve the problems in energy variational theory for analyzing the shear lag effect on box girder, the longitudinal displacement expression of the flange section of box girder was established by the additional deflection function instead of the shear lag function of box girder. The total potential energy functional of box girder was developed using external load instead of inner force. Fourth-order governing differential equations and various boundary conditions under shear lag effect were derived according to variational principle. The decoupling solution method was presented for the deflection and the additional deflection of box girder as well as the deflection of classical beam under shear lag effect. The boundary conditions at the free end of box girder under shear lag effect and closed-form solution to the response of the box girder clamped at one end and simply supported at another end were obtained for the first time. Example analysis has demonstrated the effectiveness and calculation accuracy of the proposed method. Meanwhile, the boundary conditions are quite same for both the deflection and additional deflection of box girder, but are different from those of Euler beam at the free end.

• 出版日期2014
• 单位桂林理工大学; 广西大学