Where is the deck longitudinal joint come from?

[centralstate]

Can someone tell me where is the deck longitudinal joint came from? AASHTO?
Per IDOT bridge manual, we need to place deck longitudinal joint if deck width over 90 feet. But where is it come from and what is the purpose?

Thank you.

 

[rowe]

The specification of placing a longitudinal joint in a bridge deck is usually the result of concerns about cracking due to concrete shrinkage, and easier construction (some contractors may not have a screed long enough to span the >90 width of the deck).

DOTs usually have a preference based upon previous performance of bridges already in service.

 

[curvbridger]

I do not know what you mean about the origin of the longitudinal deck joint.

The idea here seems to be to limits effects in the transverse direction. Think about it: If you had a bridge LENGTH of 100 feet, would you not expect significant movement at the ends? Limiting the width serves to keep the line girder assumptions valid, and keeps bearing design and detailing simple.

I suggest using a deck-supported neoprene box seal gland in a steel extrusion for a longitudinal joint, but watch your end conditions! They can be troublesome.

Curvbridger