chambering beam

[mnzevil]

hello i would like to ask a help from you guys...rite now im doing some bridge work with 36meter and it need pre-chamber beam around 70mm how do i do the this 2 main beam chambering 

i got 2 option 

1 -curve the main beam

2-chamber at the joint connection 

please help

[Dias_Antonio]

Hi

I did not understand the term "chamber beam" or "beam chambering". Can you post a zoom detail?

[johnjmbennett]

Camber is a pre bend placed into the beam, to create a small curve to the beam.   Typically applied in floor beams, to preset the beam , so when it is loaded with concrete slabs the in build pre camber counteracts the induced deflection of the floor load.

for a bridge detail, I would suggest that you model to a curved of the camber height, but typically doing this will mean that a lot of the connections will require a manually interaction.

you can use the camber option, and it will model it straight, but with option to create a camber drawing of the straight beam, via a drawing style.

tbh, I would say it is personal preference and the extent of the deflection path that is being induced by the loadings.

[Dias_Antonio]

@johnjmbennett 

Now I understood well. Thanks.

[mnzevil]

Btw if i used this option is it effect the hole arrangment and the clashing?? because on the model it show straight beam,,but on single part it show chambering beam aroud 10mm on every beam?

i really want to used this option if not i need to redraw the main beam,,it will set me back..

btw thank for kind reply..

[johnjmbennett · Accepted solution]

from what I recall, you can designate a camber beam drawing style as well as straight beam style for the single part presentation within the outputs. 

typically I the steel member will have a natural curve within it,  in the shop I have seen fabricators use this natural curve to aide the cambering process,  as it is noted on the drawing as a pre process to the manufacture etc.   also some steel providers also provide the pre cambering as an option when ordering the steel.       

depending upon the camber height, then you may choose not to show this within the single part drawings that have holes drilled etc, as the measurement differences in the real world are impossible to achieve,  but work with the natural deflection of the beam to achieve the camber. 

link to an article over the use of the camber drawing style and its implementation.

https://graitec.com/uk/resources/technical-support/documentation/technical-faqs/faq-2297-how-is-a-dr...

please bear in mid though if the camber height is large and the span has several deflections implied, then you should consider modelling as a curved beam or  poly beam if multiple deflections are induced in the design. 

HTH