Deformation Induced Cracking in Steel Girder Bridges and Retrofit Guidelines

摘要

Cracks have been found in the webs of steel girder bridges at details with small web gaps subjected to out-of-plane deformation. Both multigirder and floorbeam-girder bridges were studied. The study included field inspections, field measurements of stresses, laboratory examination of core samples, and analytical modeling. The stresses due to out-of-plane displacement are highly localized in the vicinity of the web gap regions. Finite element models showed good agreement between computed and measured stresses in the gap regions. Parametric studies were also carried out to examine the major factors which cause adverse stress distributions in these gap regions. Stress redistribution after development of through-thickness cracks were examined analytically. Retrofit schemes and guidelines for design were developed.