Wall definitions

An IMPACT definition is a combination of a Revit family (system family for walls) and different settings which together enables the IMPACT user to draw elements and at the same time get automation, e.g. automatic lifters.

To access the wall definitions, go to IMPACT - Elements - Walls. On the project level, there are a few definitions prepared for this course. We are going to take a look at the definition of the sandwich wall. Select 'SW34' by filtering out the 'Sandwich' in the drop-down for type.

Figure 1. Select sandwich definition.

General

The first tab of the definition contains information about the geometry and a few settings. 

Figure 2. General tab.

1. The first part is the configuration of the geometry, where the material and thickness of the different panels are specified. There is also a possibility to configure sublayers, such as the right part of the picture in Figure 3 below. Note that the insulation layer is divided in two, but the total thicknesses are still the same as in the left part. 
   
   Figure 3. Wall Layer Structure.
    
2. For sandwich walls, it is important to specify which panel should be up and down in the mold. The reason is that the panel which is down will have a smooth surface since the mold is flat at the bottom.
   
   Figure 4. Cast Type.
    
3. To get automatic reinforcement in the elements, one should select a default Reinforcement Template. This will add meshes and reinforcement around the element edges and openings.
   
   Figure 5. Reinforcement Template
    
4. The layout setting controls if and how elements higher than the maximum element height should be rotated on the drawing.
   
   Figure 6. Layout

Lift and Bracing

To get automated lifts and bracings, we need to configure which cast-in materials to use, as well as a set of rules of how and when they should be used.

Figure 7. Lift and Bracing tab.

1. The top left area of the tab contains the ruleset of how and when to insert the different cast-in materials. The first three parameters decide if one, two, or four lifters should be added to the element based on the length of the element. In the case of four lifters, they will be placed in pairs and the parameter 'Spacing 4 lift points' will control the distance between the lifters in the pair. 
   
   Figure 8. Description of lift settings.
   
   With the default lift types, you can configure two or more setups of cast-in materials, and select which setup should be the default one. An example is the lift angle. The lifters in Figure 7 above are configured for a lift angle of 60°. If the same lift should be used with another lift angle, it should be able to handle more or less mass.
   
   Figure 9. The same lifter with two different lift angles.
   
   There are two different default lifters. Since we also have the possibility to handle elements that are higher than a specified maximum. These walls are cast and transported laying down. This requires additional lifters on either left or right side of the element. 
   
   Figure 10. Walls that are too high are rotated and lifters are inserted into a second side of the element.
   
   The rotation for asymmetrical lifters can be controlled with the rotation on each side.
2. We already know that an element can have one, two, or four lifters inserted. Normally, these three differ in lift type and capacity. To solve this, we have three configurations of cast-in materials to be used as lifters. One for each number of lifts used. 
   
   Figure 11. Select the number of lifters to configure.
   
   In the configuration of the cast-in materials, the family types are selected and the user decides which lift type (e.g. lift angle) this component should be used for. The max capacity of mass is also added. This information is used in combination with the rules in section 1 above to optimize which and how many lifts are used in each element. 
   
   Figure 12. List of cast-in materials.
    
3. In addition to the lifters, bracings are also added automatically when the wall is drawn. It is a bit less complex since there will only be one type of bracing used in all elements with the same definition. 
    
4. The placement of the bracings is pretty simple. For the placement in the length direction, there are three options:
   1. Fixed distance - placed with a fixed distance from the side of the element. 
   2. Part of length - placed with a distance depending on the length of the element. 
   3. Center of gravity - placed according to the center of gravity.
      
      Figure 13. Placement of bracing in the x-direction.
      
      The placement in the height direction offers two alternatives.
      
      Figure 14. Placement of bracing in the y-direction.

Naming

The last tab in the definition contains information about naming conventions and filtering options. 

1. Group - a definition can be included in a group which makes it easy to filter out the walls later on e.g. the IMPACT Production applications. An example could be that we have two definitions for a sandwich wall which is 340mm thick. The difference is the cast-in material used for the lifts. This may not be important for the people in the production, but they just want to know if these two walls are in the group 200-300mm or 300-400mm. To solve this, we can use the group parameter. 
2. Product - another filter parameter.
3. Prefix designation - on the drawings, there is an option to add a so-called designation that contains a prefix and the element thickness in centimeters + element height in centimeters. 
   
   Figure 15. Designation of the element.
    
4. Prefix element mark - the naming of the elements. 
5. Prefix drawing name - sometimes, the naming of the element and drawings are not the same. In those cases we can use this parameter to control the prefix for drawings. 

Figure 16. Naming tab.

The last information that can be added to the naming tab is the 'Building Information Properties' (BIP). These are used to get better information from combined models.

Figure 17. Building Information Properties (BIP).

We have now looked at how the definition is configured. The next step is to draw some walls ourselves. 

Next: Draw walls