while modelling a 2d box culvert in

[Amogh Deshpande]

while modelling a 2d box culvert in STAAD Pro what kind of support conditions are required. Is it fixed , pinned or spring support to account for soil stiffness. In case of Spring supports is it necessary to consider the upward reaction by soil or should it be neglected

 

[HTURKAK]

Have a look to the following link.

https://www.sefindia.org/forum/viewtopic.php?t=14857

...

He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48

 

[Amogh Deshpande]

Is it necessary that the maximum Bending moment in culvert slab shall come at the center section of the slab? and maximum shear force near the support sections.Please solve my query.

 

[HTURKAK]

- The max. sagging moment should develop , the most likely place is at the center of the slab,
- Develop a FEM model ( the bottom elements are supported on Winkler springs ) and see the effects.
- The loads are overburden , traffic for the top slab and you may assume at rest soil pressure for the walls
..




He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48

 

[Amogh Deshpande]

Yes I modelled it using spring by giving Stiffness of spring in Y direction in fixed but support option without giving any release but still I am getting the maximum bending moment near support section for bottom slab where as for top slab maximum moment is at center. Kindly help me I am confused why its happening like this.Which release should be provided in fixed but support condition for Spring model?

 

[HTURKAK]

It is hard to visualize your model with your description. Pls post your model to get better responds. what is support option?
You may look to the following doc. to get better insight.

https://vdocuments.mx/dmrb-volume-2-section-2-part-12-bd-3101-the-design-.html?page=10

..

He is like a man building a house, who dug deep and laid the foundation on the rock. And when the flood arose, the stream beat vehemently against that house, and could not shake it, for it was founded on the rock..

Luke 6:48

 

[Amogh Deshpande]

Yes i have uploaded my STAAD file. I cant understand why the maximum moments are not at the center section.
file link :

https://files.engineering.com/getfi...-e30b-4bde-a639-a2fbe7dc6eff&file=4_x_2.5.std

 

[robyengIT]

another possibility

 

[JoelTXCive]

How big is your box culvert?

Many state DOT's have pre-cast and cast-in-place designs that go up to 10x10 (maybe even 12x12). The DOT's use HL-93 loading, so if you have a plane or railroad loading, then they won't work.