Line beam automated loading for CS 454

[Shayma_Fleet8R47X]

I am using SBD 2025 to model a 3 span continuous preflexed steel beam as a simple composite line beam. I want to use the automated loading function to apply HA and HB loading to the beam, but there is only the option for a live load envelope for BD 37/01 (which is more onerous than CS 454). Can this function be manipulated to apply loading to CS 454 instead?

Any advice would be appreciated - I was also hoping to apply SV load models in due course. Line beam analysis had originally been suggested over full grillage in the name of saving time, but this will only be the case if vehicle loading doesn't need applying/optimising manually. 

[simon_hooper]

Hi Shayma

CS 454 for line beam analysis is unlikely due to the transverse nature of the loading patterns. I would suggest creating a grillage.  If you have the design beams it is relatively simple to add a refined grillage model to your project and to complete the CS 454 live load optimization.

Also, you could consider using InfraWorks to create the grillage model for your bridge to save time.

Thanks

Simon

[Shayma_Fleet8R47X]

Hi Simon, thanks for the response.

I'm a little confused about CS 454 loading being unlikely due to transverse nature of the loading patterns, as how is it different from BD 31/01 (particularly ALL Model 2, which follows a similar loading pattern)? Could you elaborate a bit what you mean by that?

Shame that it seems there is no option for autoload, or moving load capabilities for manual loads in the software for this -  it would be great for simplicities sake, even if it might be unduly conservative for a line beam. 

[simon_hooper]

By transverse nature, I was thinking about the way we optimize the number of lanes and how the pattern varies across the structure according to CS454 rules, e.g.

But, I guess it could be implemented with various simplifications.