The Evaluation of Basler’s Theory in Plate Web Post-Buckling

Abstract

Basler in 1963 provided the well-known theory to explain the post-buckling behavior of the plate webs in girders by using the diagonal tension field. Basler’s theory has been adopted in the AASHTO code since 1971, regardless of the drawbacks which were indicated in the past several decades. By means of the finite element analysis combined with the existing experimental shear tests, the present study reveals that for square web panel with the ratio t_f/t_w=4, Basler’s predictions correlate excellently with the results from the present FEM models which is perfectly contrary to Basler’s model in the physical meaning. This behavior also indicates that the good correlation between the results calculated by Basler’s formula with test results is not trustworthy. In case it accepts the existing paradox in Basler’s theory, Basler’s tension theory can still provide an acceptable prediction in a certain range of parameters, but this tension field is invalid for a long web panel. Finally, the present study will shed light on the controversy about Basler's theory. The results of this study with high web slenderness can be further researched for aerodrome structures.