Load distribution for hollow core u

[DC_Engr]

Hi
I have a hollow core system that has load bearing walls running on top of it—- perpendicular to span of hollow core system and there are still some hollow core slabs which are subject to additional point load, or running load parallel to its span, would you still use load distribution for such a system of hollow core slab if the load due to walls perpendicular to span of hollow core can be handled by the slabs on their own without getting over stressed?

 

[BAretired]

Sounds like you have bearing walls running both perpendicular and parallel to the hollow core slabs. Definitely not an ideal situation. The hollow core slab design will likely require a bit of engineering judgment to determine how it responds to such a load. With the information provided, you cannot reasonably expect any kind of well considered response.

 

[KootK]

1) I feel that the presence of the transverse bearing wall in no way worsens the load sharing available for the other loads.

2) I feel that the presence of the transvers bearing wall would, in many cases, enhance the load sharing available for the other loads depending on:

a) How stiff the bearing wall is (concrete vs wood etc).

b) Whether or not the additional loads would ever, in an location, cause the plank to pull away from the bearing wall in tension.

c) Whether or not the plank is detailed to be able to hang from the bearing wall to some degree.

3) In summary, I'd be willing to exploit load sharing for all of the loads but I wouldn't normally bother attempting anything more aggressive than that.

 

[DC_Engr]

thanks BAretired! Some walls are labeled as “Shear walls” with a seismic up/down force specified at ends. Granted that full seismic load will not act concurrently for both E/W and N/S walls, nor code requires any orthogonal combination. Surprisingly most of the hollow core seems to fail only for horizontal shear or 1.2Mcr requirement of ACI code. There’s not much that can be done for horizontal shear on a hollow core in my opinion. Thoughts?

 

[structSU10]

Are the planks topped? I have also seen cores grouted solid with added bar to help with capacity for special conditions. The hollowcore is generally designed by the precaster - is that your role?