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.
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.
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.
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
Do similar with parcels
To style the parcels in the map
Defining AOI Elevation, Sewer, Water, Tract bearings
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.
Otherwise save as L-TOPO-TEMp.dwg and define a property alteration query to move the polyline to the correct elavation with following steps:
Building inner and other surface
Photogrammetry data Recap for processing
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
current coordinate system: LL83
target coordinate system: CA83IIIF
decimation: 0 mm