**9. Methodological steps for designing road elements using Civil 3D Land Desktop and GIS software**

In order to define the proposed road path and all its horizontal and vertical and design elements, these points will be used in the definition and design of road elements according to the following methodological steps:


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**Figure 6.**

**Figure 5.**

*Modify coordinates of survey points.*

• The design speed = 100 km/h.

*Constructing the TIN surface to link between coordinates.*

• Maximum side slope = 4/1.

• Maximum longitudinal slope = 3%.

• Stopping sight distance SSD = 185 m.

*Building an Integrated Database of Road Design Elements*

*DOI: http://dx.doi.org/10.5772/intechopen.88678*

**Figure 4.** *Configuration of units, scale, projection of Civil 3D program.* *Geographic Information Systems in Geospatial Intelligence*

**Desktop and GIS software**

and exported to the civil 3D.

*Configuration of units, scale, projection of Civil 3D program.*

contains an integrated database ready for implementation.

ments according to the following methodological steps:

exported to GIS as digital elevation model (DEM).

In the Civil 3D program, all the design elements of the road will be defined according to the AASHTO standards, leading to the final stage where the road

**9. Methodological steps for designing road elements using Civil 3D Land** 

In order to define the proposed road path and all its horizontal and vertical and design elements, these points will be used in the definition and design of road ele-

b.The survey points were imported within the program and arranged and modified (point number, coordinates values, elevations) to be ready for the purpose of design road elements, as in **Figure 5**. Constructing a surface triangulated irregular network (TIN) and connecting the points' coordinates for the purpose of deriving the elevations of the road depending on it, as in **Figure 6**. The TIN surface is then

c.The Geographic Information system (GIS) program was used to select the best route for the road connecting the city of Makhmour with the city of Mosul, as in **Figure 7** which shows the sequence of steps to choose the path. The network of TIN has been reclassified according to the elevation values, so that the road passes from the flat areas as much as possible, as the land on which the road passes has steep slopes. The land use layer has been reclassified so as not to cross the road with any unwanted land use. The best and shortest route between the two urban areas was then chosen. The length of the best selected path was 18210.88 m. Its alignment, stations, width, and number of lanes were defined

d.ASHTO standards were adopted in the design of horizontal elements of the proposed highway. These design elements were defined to the Civil 3D as follows:

a.The civil 3D land desktop program has been configured to be in meter units, 1:1000 horizontal scale and 1:50 vertical scale, UTM, WGS 84 Datum as **Figure 4**.

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**Figure 4.**

**Figure 5.** *Modify coordinates of survey points.*
