Cast-in-Place Bridge Abutment
Cast-in-Place Bridge Abutment
(OP)
I'm currently designing a bridge abutment for a pre-engineered steel bridge.
I have done similar designs in the past.
The bridge is a 40'x16' single span with one fixed bearing and one expansion bearing.
A colleague advised me that I should design the abutment stem assuming that the bridge superstructure provides lateral support.
Through my research and study I have found that if a bridge has a fixed bearing at one end and an expansion at the other both abutments should be designed as free cantilevers. Is this correct?
Should the stem deflection be calculated to determine adequate stiffness? If so, where could I find a good reference outlining this procedure?
Thank you for your time,
Wyoming E-I-T
I have done similar designs in the past.
The bridge is a 40'x16' single span with one fixed bearing and one expansion bearing.
A colleague advised me that I should design the abutment stem assuming that the bridge superstructure provides lateral support.
Through my research and study I have found that if a bridge has a fixed bearing at one end and an expansion at the other both abutments should be designed as free cantilevers. Is this correct?
Should the stem deflection be calculated to determine adequate stiffness? If so, where could I find a good reference outlining this procedure?
Thank you for your time,
Wyoming E-I-T






RE: Cast-in-Place Bridge Abutment
For non-integral systems such as yours it is NOT common practice to utilize the bridge superstructure as lateral (longitudinal) support.
A common controlling load case for abutment designs is the construction case, when the abutment is partially or completely backfilled with a construction surcharge but without the superstructure dead load. This typically controls the sliding check and possibly the stem reinforcing.
Another thought to consider is the appropriate earth pressure (active or at-rest) to use for the abutment design. A very stiff abutment system and/or restraint provided by the superstructure could result in higher at-rest earth pressures that should be accounted for in the design.
RE: Cast-in-Place Bridge Abutment
RE: Cast-in-Place Bridge Abutment
RE: Cast-in-Place Bridge Abutment
Ciao.
RE: Cast-in-Place Bridge Abutment
RE: Cast-in-Place Bridge Abutment
Good luck