Carpark slab modeling

[Wes Macaulay]

How do any of you handle the slopes and twists of parkade slabs? I've got a stripped-down methodology that isn't terrible accurate, but I have projects and my clients have projects where we'd like to model these with a degree of accuracy.

Having spent a day or two looking at the problem I have seen that geometrically, these things are messy and modeling them is not straightforward.

Anyone's experiences or suggestions would be welcome.

[Merlin]

How do any of you handle the slopes and twists of parkade slabs? I've got a stripped-down methodology that isn't terrible accurate, but I have projects and my clients have projects where we'd like to model these with a degree of accuracy.

Having spent a day or two looking at the problem I have seen that geometrically, these things are messy and modeling them is not straightforward.

Anyone's experiences or suggestions would be welcome.

Hi Wes,
Yes, It's a bit of a worry....fall arrows are fine for a slab with one slope....but of course many cases require more than one fall in different directions.

To date, I've only indicated the directions of falls with annotations; this could be a problem when I come across places where the fall is significant and I would have to dimension it.

John Mc

[beegee]

I've had clients build parking areas using topo surfaces.

I don't recommend that approach.

Mostly I do as John Mc and just use annotations to indicate complex falls, which don't need to be seen accurately in models. That may need enhancement in sections, depending on the extent.

Otherwise, its cutting with voids which can get rather difficult for some shapes.

[eldad]

have you tried doing it with the roof tool? that way you can have a few falls, and just give it a concrete material...

i rather use flat slab and annotate... :)

[Dimitri Harvalias]

In situations where sloped slabs are not practical I've used a combination of blends and extrusions. It makes multiple wall sections a little easier to deal with because you get an accurate representation this way. The only issue has to do with not being able to get 'real' spot elevations anywhere on the surface, only on edges.
I still think Revit needs a simpler way to create slabs as a series of spot elevations that the software interpolates (a slab topo if you will). Scott Davis once suggested an area drain family that had an elevation parameter. Stick them in at the correct elvations and have Revit build a slab around them.
Who's the wish list manager around here? We should get him on this :)

[Wes Macaulay]

I started working on an Excel spreadsheet that would help me calculate the geometry of the blends (basically the elevation at each end of the lines in the sketches) but ran into so many different situations that this proved useless. So now I figure out the blended solids and extruded voids manually, and it's more laborious than I'd like.

We only need spots along the edges of the slab so we don't need my second-rate workaround of a floor hosted void family to create that small nick in the slab so you can pop a spot elevation onto it...

What a challenge is the lowly carpark slab... and yes, I will add this to the wishlist! :mrgreen:

[Scott D Davis]

We have the same problem in Warped roofs...where each joist shares a common ridge, but the tail of each joist falls in elevation a bit more than the previous. This is common for parapet roofs, rather than using crickets. Imagine a constant ridge beam with a sloped Rim Joist. I ended up creating Masses with blends, then Roof by Face to create them.

I've requested directly to Tatjana, that spot elevations be able to control roof elevations. I should be able to draw a roof "mass" flat, tag the four corners with spot elevations, then change the spot elevations to the coorect dimensions. The mass should change shape to "warp" to the desited points.

I've also requested that a Roof Drain have properties that when placed, will automatically reshape a roof to slope to the drain.

[Wes Macaulay]

Woah Scott -- you don't ask for much, do ya? Like the ideas a lot...

[Merlin]

Woah Scott -- you don't ask for much, do ya? Like the ideas a lot...
Actually, Scott raises a good point with that. I had a case where I wanted a raking fascia gutter, but, alas, the general sweep wouldn't work.(Peculiar, knowing that the raking fascia could be produced easily enough.)

It seems like a general call for controls of falls/slopes in many areas would be desirable, Wes.

John Mc

[mmodernc]

topo - 3D export to dwg- import into massing family- convert to curtain system-use concrete panels

[janunson]

I've also had this problem... Made the slabs in 3D studio and imported them.

[Merlin]

I think if I needed to do it, I'd just use the massing tools. Having said that, it'd probabley have improper joins (ie no joins!)

[Wes Macaulay]

mmodernc gets the dozen donuts from Tim Horton's as his prize... I might just try that one!

Cheers

[janunson]

topo - 3D export to dwg- import into massing family- convert to curtain system-use concrete panels
slick! Might try that one, would be a great next step for the 3D Studio imports too.

[mmodernc]

Are they fat free? If you don't like the triangulation lines you can use the linework tool to make the joins invisible. You may also need to align any textures if they are geometric rather than random.

[eldad]

I made a little tutorial for people new to this issue... any comments welcomed,

the tutorial is creating a simple shape but can be applied to anything... :)