fatigue stress category of riveted built-up members
fatigue stress category of riveted built-up members
(OP)
hello,
I've been doing extensive research related to this issue, I am assessing a riveted steel railway bridge, making use of AREMA code.
The issue I faced was that there is no clear stress category for riveted built-up sections: it only gives for welded bult-up section
(category B to E), and also gives cateogry for riveted connections (category D), I was wandering what category to use in riveted
built-up sections since they have much more redundancy when compared to the riveted joints.
I should still use category D, or as suggested by some papers use category C?
I've been doing extensive research related to this issue, I am assessing a riveted steel railway bridge, making use of AREMA code.
The issue I faced was that there is no clear stress category for riveted built-up sections: it only gives for welded bult-up section
(category B to E), and also gives cateogry for riveted connections (category D), I was wandering what category to use in riveted
built-up sections since they have much more redundancy when compared to the riveted joints.
I should still use category D, or as suggested by some papers use category C?





RE: fatigue stress category of riveted built-up members
There's research that suggests the fatigue category should be C. However, AASHTO Standard Specs require Category D - but this is for new designs. The sample example, 2.3, in LRFD doesn't mention rivets but it's still Category D. AASHTO's Bridge Evaluation Manual permits Category C for existing structures.
The project I was on ended up using Category D because technically (or perhaps legally is more appropriate term) the BEM is not a specification.
Theoretically, if you replace (certain) rivets with high strength bolts the fatigue life problem goes away because you reset the clock using Category B.