If you are going to use the Snap to Contour, you might want to adjust the Site Model Settings to give you the correct contour to snap to. The second method is to adjust the Start Contour Offset to change the elevation of all of the contours .
The settings for the Maximum and Minimum elevations allow you to choose how much of the site model you see. Think of these settings as a filter, choosing how much of the site model you want to see. For example, you might have a site model that goes from sea level to 100m, but the building site is around 85m. You could filter the site model from 65m-95m, so that you only see the important parts.
In this session we looked at site modelling again. In particular, we looked at a special case where we wanted to create site modifiers above the site model (it’s actually a construction pad above the level of the site model for drainage). This is probably the first time that we have looked at the concept of site modelling, how it actually works and I’ve drawn an example to show exactly how Vectorworks calculates the contours.
I had a client ask about this dialog box the other day. They thought that it was a bit confusing and wondered if it would affect the site model. The answer is that it only affects the visual presentation of the site model and does not affect the mathmatics behind the model. The Maximum and mimimum settings are used to filter the presentation of the model to the elevations that you want. The reason for the dialog is that something that you have created (something that affects the site model) is above the maximun elevation or is below the minimum elevation. Vecotrworks is asking if you want to change the maximum and minimum settings so that you can see the new obejct and its affect on the site model.
Intermediate – Normally, you have to use a grade limits with a site modifier, but not when use a pad with retaining edge. In this image you can see a pad with a vertical retaining each. At the bottom you can see the red outline itches the pad, and at the top you can see the red outline which is the retaining edge. Vectorworks will create the retaining edge to sit at exactly the right height for the existing site model if you use the command Send to Surface.
A site model is a way of looking at 3D data (spot levels or contours) in a way that allows you to see complex 3D models and 2D representations. VectorWorks uses the 3D information to create the models based on the data to help you understand the 2D and 3D nature of your site.
First you have to put in 3D data, such as spot levels, contours or surveyor’s file. Then you ask VectorWorks to create a site model from this data. VectorWorks uses a set of algorithms to analyze the information and then creates the 2D and 3D representations. The algorithms can be thought of as a set of mathematical assumptions that are used to calculate the 2D contours and 3D model. Because of these assumptions you may get some odd shaped contours, or 3D models that don’t look as you expected. A Site Model is not reality, it’s a mathematical model of the data you give VectorWorks. Better data – better Site Model.
Creating A Site Model Snapshot – A site model snapshot is a way of keeping a view of the site model. For example, you might want to see the existing site model and the proposed site mode at the same time, you might want to see smoothed contours and shaded contours at the same time.
Editing Site Model Labels – The site model has labels on each major contour which can be edited with the Reshape tool.
Editing The Site Model Crop – The site model crop is a polygon that stretches around the information you have supplied to Vectorworks. The site model crop works a lot like the crop in the viewport. The site model crop can also be edited to filter out information that you do not want to show.
Adding Additional Site Model Data – You might sometimes find that the resulting site model does not have the contours you thought it would have. In this situation, more spot levels along the contours might be useful. When you need to add information to the site model, even after you have made the site model, you can.
Creating the Site Model – A site model is created from 3D loci, 3D polygons or stake objects. You can use any of these types and you can use a combination of these.
Importing A Survey Drawing With 3D Information – When you import a survey file, you often have the choice whether you want to import the information as 2D or 3D. For very large sites, it is a lot of work to input 3D loci, stake objects, to tracing polygons. If you can use the 3D information from the survey file, you will save hours.
In the session we looked at site modelling and site modifiers. In particular, we looked at the site model settings to see how to edit the site model labels and crop area using the Reshape tool we looked at a simple site modifier. We used the command Create Objects From Shapes… to convert a simple object into a site modifier (pad).
Using the Offset tool, the pad was copied and converted to a Grade Limits. The pad was set to have a slope and then a polygon was converted to a site modifier and used as the top of a retaining wall. We also looked at creating site model snapshots. Snapshots are very powerful for creating different views of a site model, they update when you update the site model. We also looked at to road tools: the NURBS roadway and the Polygon roadway. These roads can be site modifiers and you can adjust the elevations of the roads to suit the site or to suit the design.
If you going to create recession planes for your site model so that you can see the restrictions on your site in 3-D, make sure you place stake objects at the point where the surveyor has taken on the measurements. This will improve the reliability and accuracy of your recession planes.
In this session we looked at setting up a project that has a site model with two different houses on it. There are different ways to set this up; it could be set up in three files which could be connected together using referencing, the file could be set up using stories (maybe), or the two houses could be set up in one file and use Design Layer Viewports to place the houses on the site. Referencing the files together has been discounted for this project because one of the users wanted to keep all of the project work in one file.
We looked at stories but found they do not work for this project because we want to have two independent houses with different floor levels. The favoured solution for this project is to set up the required layers using one layer for the floor and one layer for the roof of each house. When the houses are created they can be linked to the site model using Design Layer Viewports. This is a flexible option and that allows the houses to be repositioned easily and have their elevations independently adjusted. We looked at quickly drawing the walls and roof and linking these buildings to the site. As we adjusted the design of the buildings you can see them update on the site straight away.
Adding Spot Levels Using Stake Objects – You can use the Stake object, or 3D loci to create additional data for the site model. This is useful for placing points that match the survey information.
Grid Entry Method – A common way to survey a site is to use a grid. With this method, set up a regular grid for northings and eastings. It is important that the grid is consistent as Vectorworks assumes that you have regular spacings. It is also important to understand that the grid in Vectorworks is orthogonal on the screen. If you want the grid to follow one of the boundaries, use the Rotate Plan tool first.