Expansion/fixed bearing locations for single span bridge
Expansion/fixed bearing locations for single span bridge
(OP)
I'm designing a single span bridge with elastomeric bearings. End bent 1 is higher in elevation than end bent 2. Which end bent should use expansion bearings and which end bent should use fixed bearings? I think I remember reading that there was an advantage to using fixed bearings at the lower end bent, but I can't remember the reasoning or the source. I would appreciate any feedback you may have. Thanks!





RE: Expansion/fixed bearing locations for single span bridge
Perhaps you could eliminate the expansion bearing altogether if your end bents are designed to allow movement (i.e. single row of piles). Good luck.
RE: Expansion/fixed bearing locations for single span bridge
An additional benefit to this arrangement is that it should help prevent runoff from reaching and deteriorating the bearings. The drainage may be collected/diverted off the roadway prior to reaching the expansion joint. The runoff on the bridge deck itself will then pass over the fixed (and closed) downhill end.
RE: Expansion/fixed bearing locations for single span bridge
For the abutments itself it would seem that having the deck weight pushing into the soil behind it would be a better solution than pulling it away from the soil as crossframe stated.
RE: Expansion/fixed bearing locations for single span bridge
The trend has been occuring since about 1940.
The downside is the that people don't like to see cracks.