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jrichardson
2006-02-11, 02:13 PM
Is it possible to model a slab as Hollow Core Precast Plank. Similar to the Metal deck and composite slab. I would not need to show the plank as several planks with a set width side by side. Just a representation of the hollow core. I could than pick my span direction and any jogs are columns and corners would be determined by how I draw my slab edge. I tried to modify the roof deck profile to get it to show through in the slab command but had no luck. I do not want to have to place each span of plank individually as a beam. If this is something that can not be done at this time, I would like to add it to the wish list. How are others doing this?

thanks,
jamie

aggockel50321
2006-02-11, 02:42 PM
One method:

Open a structural beam family, & model your precast plank.

Load it into your project, and use the beam system command (structural tab) to lay the planks.

Firmso
2006-08-10, 04:01 AM
One method:

Open a structural beam family, & model your precast plank.

Load it into your project, and use the beam system command (structural tab) to lay the planks.
....and do a void inside the beam so that it will be hollow when you load it into your project....
making sure it flexes with the beam system.

phoulx
2009-04-07, 09:05 PM
The original post here is exactly what I'm looking for. A simple slab approach showing the span direction on plan and voids/dashed lines in details. In section, the "slab" representation can be replaced with a more accurate 2D version.

Anything more is just overmodeling unless you are the precast manufacturer. An architect or engineer probably won't know who the precast supplier is (are they round voids or oval voids?) or exactly how the planks will be placed (three 4' and one 1', two 4' and two 2' and one 1',...). All that depends on the precast supplier, I just need to show thickness and span direction.

I took the metal deck idea but can't get it to look that great. Anyone else have an idea?

benmay
2009-04-07, 11:04 PM
I dont think a using a beam system is overmodelling, using a structual deck profile is fine for preliminary but at documentation stage I believe you need to know where your planks are setout from and how they relate to areas like setdowns, and balconies etc.

Structual deck will only ever give you a 2D sectional profile, you cannot see your deck in plan

But if you dont need to co-ordinate the setout of the precast planks then go for the structural deck, can you post a screenshot of what isnt working for you?

phoulx
2009-04-08, 03:30 PM
All I'm responsible for is footprint, thickness, span direction and loading criteria. That would be perfect as a floor. I define a thickness, sketch a footprint, rotate span direction. I quickly looked at revising a composite floor and came up with this ugly thing. I could just use an 8" concrete slab but I would rather be able to show the span direction in section, if only for representational purposes only. I'll clean it up in section where necessary anyway.

I don't see any point in modeling beyond that as there are too many supplier considerations. Again, I'm not the precaster, I'll let them do their job. What happens with floor openings or odd shaped floor plans? Will they shuffle around the plank layout to fit or just cut and fill? Same as metal stud or wood trusses, I don't know what the web layout or member dimensions are so why give myself extra work by modeling something that I know will not be accurate?

Jshaver
2009-04-09, 08:58 PM
The approach truly depends on the complexity of your project and your modeling efficiency. Personally I prefer to model the individual planks provided I can obtain accurate precast manufacturer specs.
When creating the family it is best to take into consideration the relationships between family types and settings. (You dont want the hollowcore planks joining improperly to the supporting girders)

A complex family that includes elements such as reinforcing and bearing pads will help aid in detailing if you are using live sectioning.

This approach worked well in conjunction with the "opening by face" command to notch out the odd bits.

haldier7
2009-04-13, 12:05 PM
I would go with the beam system which would show the analytical lines for each individual HC slab so can be used for design analysis purpose.