Pre-stressed precast bridge beam modelling - Deflection issues arising from pre-stressing
Pre-stressed precast bridge beam modelling - Deflection issues arising from pre-stressing
(OP)
Hi
I'm modelling a precast, pre-stressed bridge which consists of symmetric internal Y beams and asymmetric edge beams. My edge beams experience a horizontal deflection (as well as the expected vertical deflection) due to the pre-stressing loads. This is due to the eccentricity of my tendon layout so the resolution would be to re-arrange my tendons to account for this. Has anyone else encountered this issue? Just wondering if there is a more time efficient solution than adjusting the layout, running the model, re-adjust the layout and so on. Would I be better doing a manual calc on the forces & eccentricities, balance them and then model the resulting layout?
Regards
Cian
I'm modelling a precast, pre-stressed bridge which consists of symmetric internal Y beams and asymmetric edge beams. My edge beams experience a horizontal deflection (as well as the expected vertical deflection) due to the pre-stressing loads. This is due to the eccentricity of my tendon layout so the resolution would be to re-arrange my tendons to account for this. Has anyone else encountered this issue? Just wondering if there is a more time efficient solution than adjusting the layout, running the model, re-adjust the layout and so on. Would I be better doing a manual calc on the forces & eccentricities, balance them and then model the resulting layout?
Regards
Cian






RE: Pre-stressed precast bridge beam modelling - Deflection issues arising from pre-stressing
Also, I assume that the precaster only has so many predefined strand locations in their stressing bed so the number of available combinations can't be that large.
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
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RE: Pre-stressed precast bridge beam modelling - Deflection issues arising from pre-stressing
Doug Jenkins
Interactive Design Services
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RE: Pre-stressed precast bridge beam modelling - Deflection issues arising from pre-stressing