DOI

10.5703/1288284313224

Abstract

This report is the second of a two-part, three volume final report presenting the findings of the research work that was undertaken to evaluate the behavior of Indiana highway bridges with diaphragm members welded directly to the web of the primary beams and girders. Fatigue cracks have been observed at several bridges that utilize the welded diaphragm connection. The seriousness of the cracking and the corresponding potential risk on the integrity of the bridge superstructure were assessed. Inspection and repair guidelines for bridges with the welded diaphragm connections were also developed as part of the research effort. This volume presents the results of laboratory fatigue tests that were conducted to evaluate the cyclic life of staggered and non-staggered diaphragm connections. The performance of three different repair and retrofit procedures on the cyclic life of the welded diaphragm connection was also studied. Analytical models of the cracked diaphragm connection were developed to study the expected response under field loading conditions. Recommendation for implementation of inspection, repair, and retrofit procedures are presented. The titles of the three volumes (Report Number in parentheses) are listed: Part I, Volume 1: Field Evaluation (FHWA/IN/JTRP-2001/10-I-1) Part I, Volume 2: Laboratory Fatigue Evaluation (FHWA/IN/JTRP-2001/10-I-2) Part II: Brittle Fracture Examination of the I-64 Blue River (FHWA/IN/JTRP-2001/10-II)This report is the third of a two-part, three volume final report presenting the findings of the research work that was undertaken to evaluate the behavior of Indiana highway bridges with diaphragm members welded directly to the web of the primary beams and girders. Fatigue cracks have been observed at several bridges that utilize the welded diaphragm connection. The seriousness of the cracking and the corresponding potential risk on the integrity of the bridge superstructure were assessed. Inspection and repair guidelines for bridges with welded diaphragm connections were also developed as part of the research effort. This volume presents the results of an evaluation of a brittle fracture crack that was discovered in one of the welded plate girder members of the I-64 Blue River Bridge in Harrison County of southern Indiana. The crack, which nearly severed the exterior girder on the northern side of the east-bound structure, was located in the middle span of the three-span bridge structure. The crack extended for most of the plate girder depth before it was arrested in the compression region near the top of the girder and the concrete deck. The primary purpose of the research study was to examine the causes of the brittle fracture of the I-64 Blue River Bridge girder. In addition to understanding the reasons for the brittle fracture, possible repair and retrofit procedures were formulated to improve the fracture resistance of bridges with details similar to the Blue River Bridge. The titles of the three volumes (Report Number in parentheses) are listed below: Part I, Volume 1: Field Evaluation (FHWA/IN/JTRP-2001/10-I-1) Part I, Volume 2: Laboratory Fatigue Evaluation (FHWA/IN/JTRP-2001/10-I-2) Part II: Brittle Fracture Examination of the I-64 Blue River Bridge (FHWA/IN/JTRP-2001/10-II)

Report Number

FHWA/IN/JTRP-2001/10-II

Keywords

brittle fracture, crack, fatigue, bridge, steel, girder, attachment plate, gusset plate, web gap, differential displacement, inspection, weld repair, SPR-2113

SPR Number

2113

Project Number

C-36-56KK

File Number

7-4-37

Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

Date of this Version

2002