Dear All,
I want to check a structure due to Dead Load, Live Load and Moving Load.
SInce there are load on slab, so I create a dummy beam to cater this issue (let say for brickwall stands on slab).
Then the problem is with Moving Load. As we know that the Moving Load will be transfered to the nearest beam and the total load will be divided respectively by its distance to the nearest beam, so there some load that transfered to the dummy beam.
Do I need to remove the dummy beam? Or instead I should use dummy beam to indicate the moving load transfered to the slab?
I have checked that the moment profile of slab are different between with and without dummy beam.
Please your kindly advice.
Thank you.
Best Regards
Santos
I would generally avoid modeling a dummy beam for the purpose of applying a load to the plates. Instead you may apply the load due to the brick wall using a series of joint loads applied at the plate nodes. Of course for that you need to ensure that when you generate the plate mesh, the plate nodes should are aligned with the wall. Alternately the wall load can also be applied using the various plate loading options like ( Pressure on Full Plate, Concentrated Load or Partial plate pressure ) on a bunch of plates. That way you would not need to worry about the moving load getting assigned to these dummy members.
Regarding the moving load distribution, we can look at the arrows of moving load that always be transfered to the nearest beam. Please correct me if I'm wrong.
It means if I have a truck load that stands on the beam at one side and stands on the slab at the other side (wheel position)..and I use the moving load without any dummy beam then the load will be distributed to the beams only.
In fact, in the reality there must be point load on the slab that can't be carried out by Staad.
I think it's more representative if we use dummy beam, so we can tell Staad that there are moving load stands on the slab and on the beam.
If we don't use dummy beam, the moving load on slabs will be ignored by Staad since it's already transferred to the beam automatically.
Please correct me if I'm wrong.
First of all your understanding of how the moving load feature works is correct. I thought you were defining the dummy members for applying loads ( other than moving loads because you mentioned about applying some wall loads ) on slabs and you did NOT want these members to receive the moving loads and instead wanted the moving loads to go directly to your structural beams. My answer was aimed at addressing this requirement.
However if you would like the moving load to be applied to the slabs and then get to the structural beams, it would be appropriate to have these dummy members in the plates. Assign a dummy material with negligible E and 0 density to these dummy members. Without the dummy members, the load will directly be passed on to the structural beams without loading the slab.
I hope this helps.
Answer Verified By: SantoS
Thx a lot Mr. Sye for your kindly explanation.
Hi Mr. Sye.
Regarding this moving load, can we apply a moving load in the form of line load (not only point load)?
For example, if we want to check the moving load (heavy machine replacement location) where the machine's foundations are considered as 2 line loads (not 4 points of foundation).
Please your kindly advice about this case.