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GIS Analysis and LIM base model creation from GIS data in Civil 3D

AutoCAD® Civil 3D® is build upon a powerful GIS called Map 3D and therefore it's possible to analyze GIS data intelligently in its native format without having to seek out additional GIS software. Landscape designer tend to focus on the design tools, building terrains and roads. Because most of us who use Civil 3D are in the land development business, we tend to focus on the land development tools. This days GIS data widely available and can be used not only for analysis, but also for crration of the base drawings and modeling of the existing condition. This tutorial show, how to use the GIS functionalities of Civil 3D to perform analysis and create base models for landscape and architecture design projects from this data.

Each landscape and architecture design process starts with the analysis of existing conditions. This is often performed with special GIS software and than the base model for BIM/LIM, (a comprehansive model reflecting the existing conditions) are often rebuild than again in BIM/LIM tools, often by importing the GIS data. Imported data could include property lines, legal constraints (easements, setbacks, way of rigth, zoning ordinances), existing buildings and vegetation, topography (elavation), public services location (water, sewer, power, communication). GIS data directly into BIM/LIM software faces ollowing problems:
- GIS data coming often in large data sets and are difficult to handle, - Import of GIS data means loosing information, only the geometry data are importet - In GIS systems geometries for buildinngs are mostly surfaces, in BIM/LIM systems are mostly solids (for more information of difference between GIS and BIM see here)

Thus problems lead to an inefficient and costly processes and could be avoided by filtering and processing the data with the GIS capabilities of C3D and exporting a meaningful base drawing.

The sample project is located in San Jose, CA. Most of the data are public available from the San Jose city, Santa Clara County and US Coastal Service website.

Setting up the base GIS map for basic analysis

Template

Using the right template: This is the most efficient way to setup drawings and models correctly. With an appropriate template so we have the basic settings for units and unit related settings (like settings for dimensions, annotation scale factors for hatches etc.) inplace.
As the sample project is located in California we need imperial units, but we do not need all the NCS layers and predefined styles from the imperial template coming with Civil 3d. Instead we are using the map2.dwt template and adding later only the needed layers and styles.

Coordinate systems

Geopraphic coordinate system: They playing a crucial role in mapping data from different sources. As data are used in different bounds, scale, and scope need different coordinate systems are needed. The coordinate system used today in the US for planning and construction are the State Plane Coordinates (diveded in 124 small zones with sligthly different projections to minimize distortion). The zone for our project is CA83IIIF (California Zone 3, units: (US-Survey-)feet, datum: NAD 1983) Block for settings from EPSG

Assign the coordinate system - Switch to Settings in the Toolspace. - Right-click the current drawing and click Edit Drawing Settings.

or - use EDITDRAWINGSETTINGS in the commandline

Block for _MAPCSASSIGN vs EDITDRAWINGSETTINGS.

Adding data

In the first stage we are adding basic information (parcels, streets), hazard zone and building ordinance. All information coming as shape files (5 file per dataset),

Change to Planning and Analysis workspace

To add parcels to the map

  1. Click Home tabData panelConnect.
  2. In the Data Connect window, under Data Connections By Provider, select Add SHP Connection.
  3. Click next to the Source File field and navigate to the folder where you copied the sample files.
  4. In the Open dialog box, select PARCELS.SHP and click Open.
  5. In the Data Connect window, click Connect.
  6. In the Data Connect window, click Add To Map.
  7. Close the Data Connect window.

Do similar with parcels

To style the parcels in the map

  1. In Display Manager, select the parcels layer and click Style.
  2. In the Style Editor, click the Style entry.
  3. In the Style Line dialog box, change Color to dark gray.
  4. For Select Symbol, select a dashed pattern for the lines.
  5. Select a red, dashed pattern for the roads.
  6. Click Apply and then Close.
  7. Close the Style Editor.

Selecting the parcel and creating a layer with the selected parcel

APN: 59914012

  1. Select parcel feature class
  2. Open Data table
  3. Select row APN
  4. put apn number in to filter field
  5. apply filter

Enhancig the map

Defining AOI Elevation, Sewer, Water, Tract bearings

Attaching LiDAR data

Importing elevation data and building existing surfaces

For creating the existing surface the 1ft contour lines are used. They are coming as ESRI shape file. After import they should rsit on the right elevation.

  1. Change to workspace "Planning and Analysis"if not there yet
  2. Create a map using the map2d.dwt template and create a layer for your contour lines (V-TOPO-CNTR).
  3. Type MAPIMPORT on the command line or pick on the << image>> Icon in the Insert panel > Import tab.
  4. In the Autodesk Map Import Location dialog box, select ESRI Shape from the Import Type drop-down menu and browse to the folder where the shape file you want to import is located. Click OK.
  5. Select the file (6173_1957.shp) to import. Click OK.
  6. Limit the import area. Click on Define the window button and selectt the lower left corner and upper right corner of an area sligthly bigger than the AOI
  7. In resulting IMPORT DATA OPTIONS dialog box: a) Coordinate system: keep CA83IIIF or click in the Current Drawing Coordinate system area the icon button to select the correct system, set and Ok. b) Drawing Layer:— Select a target layer for each layer in the incoming file. V-TOPO-CNTR. c) Data: Click in the Data column, in the Attribute Data pop up window, click Create object data radio button, Under Object Data click the Select Fields… Button and select FeatId and ELEVATION. Click OK.
  8. Click OK to begin the import process.
  9. Change to a 3D view to check the result.
  10. If the contourlines are on the right elevation, than save the drawing as L-TOPO.dwg and proceed to Building site top.

Otherwise save as L-TOPO-TEMp.dwg and define a property alteration query to move the polyline to the correct elavation with following steps:

  1. Start another new drawing using the map2d.dwt template and create a layer for your contour lines (V-TOPO-CNTR).
  2. If the Map Task Pane is not currently showing, type MAPWSPACE at the command line and select On. In the Map Explorer tab, right-click Drawings and click Attach. Select L-TOPO-TEMp.dwg.
  3. In the Task Pane on the Map Explorer tab, expand Query Library, right-click Current Query and click Define.
  4. In the Define Query dialog box, click Location , in the Location Condition dialog box, select All. Click OK.
  5. In the Define Query dialog box, click the Alter Properties button and in the Set Property Alterations dialog box, click Elevation and then click the Expression button. In the Select Data dialog box, verify that the Object Data option is selected, and then select the object data field with the elevation data (ELEVATION). Click OK.
  6. In the Set Property Alterations dialog box, click Add, and then click OK.
  7. In the Define Query dialog box, verify that the Draw option is selected.
  8. Execute Query.
  9. Save the drawing as L-TOPO.dwg.

Building inner and other surface

Adding existing building data

Photogrammetry data Recap for processing

  1. LiDAR:

Point clouds are derived from raw data scanned from physical objects such as building exteriors and interiors, process plants, topographies, and manufactured items. After you collect the raw data, it must be converted to readable point cloud files. Autodesk ReCap™ converts raw scan data to scan files (RCS files), and project files (RCP files) that reference multiple RCS files. Both these formats can be attached to your drawing in AutoCAD Map 3D toolset. After that, you can add a point cloud layer to the Display Manager, where you are able to filter the point cloud data or apply color stylization.

Index drawing (tile number 196, file: 821) Download file ca2006_scwd_santaclara_821.laz Import laz into Recap Advanced settings: current coordinate system: LL83 target coordinate system: CA83IIIF
decimation: 0 mm

  1. Drawing files: Tract map