Work with non-planar slabs

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A floor and a structural foundation slab can both accommodate a slope. If required,

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a simple slope arrow can be added to the floor

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or slab to create a slope in any direction.

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The slope can either be defined with a high offset or

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you can define a slope as an angle or a ratio.

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The slope will fall in a direction of the arrow.

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You can edit the vertical surface of a floor by using the shape editing tools.

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The key difference with this and the slope arrow is that you

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can have multiple slopes with differing heights and also create nonplanar faces.

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The shape editing tools allow you to add points and change the level which is useful

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for drainage and also you can add split lines which are useful for defining gullies.

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In this video,

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we're going to first create a slope on our foundation slaps in the north of the

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structure and then we'll add two drainage points on the base of our elevator pit.

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Let's begin by opening up the site plan

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in the project browser under structural plans. Double click on site.

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We'll now zoom up on our retaining wall area here and you can see that we

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have a slab going from our retaining wall to the north of the building structure.

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This requires a slope of 2.5%

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to add the slope. We'll first select our structural foundation slab.

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And on the context ribbon, we'll select edit sketch

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on the context ribbon. Let's select the slope arrow mode

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and note here, we have two methods. We can sketch a line or we can pick a line.

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In

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this case here, I'm simply going to sketch a line.

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I'll begin in the bottom right hand corner by snapping to this end point.

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And then we'll conclude the slope arrow by snapping to the top right hand end point

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in the properties pallet.

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You'll note that the slab by default is being specified by setting a height at tile.

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What I'd like to do here is change this to slope.

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You'll now notice that we can set a slope

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in this example here, we'll type in negative 2.5%.

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Of course rev

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will then convert this into decimal degrees as you can see here.

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And also you'll note that we have a high offset of tail currently set to one inch.

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Let's make sure that this is set to zero

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to finalize these structural foundation slab.

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We'll go ahead and select finish, edit mode

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rev is asking us if we want to attach the retaining wall to this foundation slab.

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In this example, we'll say don't attach

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on the context ribbon.

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We'll select modifier to deselect the structural foundation slab

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to allow us to see this a bit clearer in the project browser under sections.

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Let's open up a retaining wall section.

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You can now clearly see that we have a slope on our slab.

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And of course, here you can see that's detailed at 2.5%.

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Let's now move on to the elevator pit

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to begin in the project browser under structural plans.

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Let's double click on elevator pit.

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We'll then zoom up on the elevator pit and you can see here that we have a floor.

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You'll also notice here that we have reference planes

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which are showing the centers of those two elevators.

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This is where our drains are going to be placed

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for the construction method of our drains.

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We simply want to add a slope on some screed

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that's going to be placed on top of our slab.

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We don't really want to edit the reinforced concrete and have a

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slope on that because obviously that makes the detailing quite complex.

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So let's begin by selecting our floor

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and in the property's pallet, let's go ahead and select edit type.

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You'll notice here that we've currently got

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a reinforced concrete slab 24 inches thick.

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We'll go ahead and edit this structure

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and here we want to add a new layer to represent our screen on top of the slab

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to do this. We'll go ahead and select insert,

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we'll use the up button to make sure that this is right at the top of the structure.

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And then we'll change our function

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to finish one.

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I'll add a material by selecting by category and then we'll select browse.

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Let's now search for

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reed in the materials browser in the search bar. We'll type in screed

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and then go ahead and select slab screen

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and click, ok.

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In the next column along, we'll add our thickness in.

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This is going to be set to two inches.

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We can now see how screen has been added to the concrete.

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A very important concept here is the column marked variable

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for each layer.

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We can decide whether this is going to be variable or a constant thickness.

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Our design goal here is to simply just add the slope to the screed itself.

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So here we can say that this thickness should vary

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but the concrete here will stay at a constant thickness.

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Let's go ahead and select OK.

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And OK. Again, to the type properties dialog box

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with the slab still selected on the context ribbon.

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You'll note here that we have our shape editing panel

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here. We can add a point,

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add a split line

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or pick structural supports to deform a slab.

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It's important to note that you can only use the

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shape editing tools on a floor or a roof.

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So in this example, here we're going to add two points. So we'll select add point,

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we'll first add a point to the intersection of the two reference planes here.

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Now I add a second point to the intersection of the reference planes here.

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We'd also add a split line in the center of the slab to do this.

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We can select add split line,

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I'll snap to the mid point on the left hand side of the boundary

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and then snap to the mid point on the right hand side of the boundary

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to deselect the floor on the context ribbon. Let's select, modify

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to help us understand how the shape editing tools are going to work on this floor.

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We'll first switch to the 3d foundation view.

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We'll then rotate the view round

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and we'll select our floor at the of O A

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pit

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on the view control toolbar. Let's select temporary hide isolate

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and here we will isolate the element.

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We can now rotate the view round and we can clearly see our floor

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note on a context ribbon. We now have modify sub elements.

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Let's select, modify sub elements.

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We can now pick one of those points that we added earlier on

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here. We're going to set this to negative one inch

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and we'll do the same on the next point. This will be negative one inch.

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OK.

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So we've now created two low points on our

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slab which are going to be the drainage locations

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to deselect the floor on the context ribbon. We'll select modifier

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and we can now clearly see that we have our depressions on the slab just on the screen

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to help us understand this better

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in the project browser. Let's open up a section here, section through elevator pit

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on closer inspection here, we can see that our concrete remains level but our

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rete in fact has a slope.

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So in summary,

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we've added a very simple slow arrow to our foundation slab to add a 2.5% fall

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and then to create a drainage solution on both of our elevator pits.

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We've used the shape editing tools on a floor.