Horizontal Reaction in Hinge-roller simple span Bridge
Horizontal Reaction in Hinge-roller simple span Bridge
(OP)
Dear All,
I am Modelling using SAP2000 a simple span bridge- R.C. deck on steel girder. My model is not 2d grillage it is a 3d shell and frame element.
the bridge consists of 4steel girder spaced 3.3mm spanning 33m and supporting a 30cm R.C. slab. the girders are hinged (the translations are restrained) from one side and the others side is roller longitudinally and hinged transversely.
the R.C slab is modeled shell element at the top flanges as the top flanges are frame element.
the PROBLEM is I get a horizontal reaction in the hinges. The summation is zero yes, but the reaction has a large value in case of eccentric live load (vehicle on the exterior girder). Vertical 70tons and horizontal 50 tons.
even when I solve the bridge as and "Eccentric-beam model" - i.e Girders are frame element , R.C. deck shell element at a distance from the frame element an connected with rigid links, I get even a higher horizontal reaction
can any one tell me what is the problem
I am Modelling using SAP2000 a simple span bridge- R.C. deck on steel girder. My model is not 2d grillage it is a 3d shell and frame element.
the bridge consists of 4steel girder spaced 3.3mm spanning 33m and supporting a 30cm R.C. slab. the girders are hinged (the translations are restrained) from one side and the others side is roller longitudinally and hinged transversely.
the R.C slab is modeled shell element at the top flanges as the top flanges are frame element.
the PROBLEM is I get a horizontal reaction in the hinges. The summation is zero yes, but the reaction has a large value in case of eccentric live load (vehicle on the exterior girder). Vertical 70tons and horizontal 50 tons.
even when I solve the bridge as and "Eccentric-beam model" - i.e Girders are frame element , R.C. deck shell element at a distance from the frame element an connected with rigid links, I get even a higher horizontal reaction
can any one tell me what is the problem






RE: Horizontal Reaction in Hinge-roller simple span Bridge
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Horizontal Reaction in Hinge-roller simple span Bridge
Paddingtongreen,
Agree with you. But I did not hear of anyone designing bridges, that he designed his hinges base to such horizontal force.
and I don't even remember seeing any hing base with a huge number of anchors in the the abutment.
This leads that: they must've been considering something else or I am missing something .
RE: Horizontal Reaction in Hinge-roller simple span Bridge
Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin
RE: Horizontal Reaction in Hinge-roller simple span Bridge
BA
RE: Horizontal Reaction in Hinge-roller simple span Bridge
RE: Horizontal Reaction in Hinge-roller simple span Bridge
Secondly, the way suggested by BAretired is perfect, all the horizontal forces disappeared, still I have to investigate the effect of seismic.
Graybeach,
I need a 3d analysis to get the straining action on the cross-bracing and horizontal (lateral) bracing. I found that the main straining actions on cross and horizontal bracing come mainly from live load cases not wind