Experimental Study on Shear Lag of Box Girder with Variable Depth under Varying Lateral Position Concentric Loads

Abstract:

This paper introduces the test and analysis of shear lag effect of a vast scale model of a continuous box girder with variable depth under symmetric lateral varying concentric loads. The strain distribution of the top plates and bottom ones of three cross-sections is tested, while the concentric loads respectively forced on the middle section and the quartile ones. Those sections are: the root-section of the cantilever, mid-section and one quartile section. Test shear lag coefficients of feature points were got through dividing the test strains to those calculated by elementary beam theory. They are compared with those soluted by method of energy variational calculus. The comparing result shows that the shear lag coefficients of the top plate shift from positive to negative accompanying with the load position from ribs to mid point of top plate. At the same time, the overall shear lag coefficient level increases. Meanwhile that of the corresponding bottom plate distribution character finely changes, but its overall shear lag coefficient declines that means that the contribution to bending resisting of bottom weakens. Lateral position of concentric loads has fine influence on shear lag of those sections relatively far from the loads.

• Periodical: Applied Mechanics and Materials (Volumes 501-504)
• Pages: 993-999
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.501-504.993
• Online since: January 2014
• Authors: Xiao Juan Shu, Xin Gu Zhong, Zhen Xing Li, Ming Yan Shen, Hong Bing Chen
• Keywords: Box Girder, Concentric Load, Experimental Study, Shear Lag, Varying Lateral Position

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