Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations MintJulep on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Fatigue Question - AASHTO LRFD

Status
Not open for further replies.

bpstruct

Structural
Joined
Apr 23, 2008
Messages
137
Location
US
Looking in the 4th Edition AASHTO LRFD - Under 5.5.3.2, trying to figure out how to apply this. The way I interpret it is to calculate the stress in the reinforcing steel resulting from the fatigue load specified in 3.6.1.4 @ 1/3 of the span from the maximum moment and compare to the applicable equation listed in this section. Is this right? Also, seems that this same stress is part of fmin (combined with other stress as indicated). Thanks for the help!
 
I understand it to mean that the equations given in 5.5.3.2 are valid for all straight reinforcement and for welded wire that does not have a cross weld in the high stress region defined by 1/3 of the span on each side of the point of maximum moment. Equation 5.5.3.1-1 must be satisfied for the entire length of the member. Fatigue I [1.5(LL+IM)] is the fatigue load and it is also combined with other loads to find the CAFT - so it does plug into both sides of equation 5.5.3.1-1.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top