题名: |
EVALUATION OF FILLET WELD QUALIFICATION
REQUIREMENTS
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作者: |
Heather E. Gilmer and Karl H. Frank |
关键词: |
welding, fillet welds, weld qualification, weld strength, weld toughness |
摘要: |
This report presents the results of a study to determine the suitability of various test specimens for the qualification of fillet welds
for steel bridges. The present AWS/AASHTO/ANSl specification uses a groove weld to qualify a fillet weld. A large root
opening is used to provide tensile and Charpy V-notch test specimens. The chemistry of a single pass or the first pass of a multiple
pass fillet weld is diluted by the base metal. The groove test weld geometry is designed to minimize die dilution of the weld metal
at the test location. In addition, the test location in the groove weld undergoes grain refinement from the overlaying welds. This
refinement does not occur in single pass fillet welds. The test program evaluated three candidate test specimens in a factorial
experiment design mat included the following variables; heat input (high and low), type of consumables (weathering, neutral flux,
and active flux), and single-sided and two-sided (Dart) welds. At least three replicate tests were performed for each condition.
The results revealed that the present groove weld test specimen does not always provide toughness results comparable to the actual
fillet welds. The weld root Charpy V-notch specimen provided a more meaningful measure of die toughness of the weld. The
shear strength of the welds exceeded the estimated nominal strength by over a factor of 2. The macroetch “T” specimen presently
required in the specification provides a simple means of evaluating both the welding procedure’s ability to provide
penetration, and the influence of the heat input from a two-sided weld. Recommended changes to the bridge welding code for
qualification requirements for fillet welds are presented.
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报告类型: |
科技报告 |