Densification


Prev		Next

In order for Patchworks to include the transportation modelling for all planning periods the road network needs to be densified to provide connectivity of each block onto the road network. This densification step provides the model with candidate roads to fill in the holes left by the existing roads and completes the connectivity of the entire road model. The model will then have the choice to 'build' the candidate roads as required to implement the management strategy.

There are two general philosophies when it comes to densifying. One involves extensive planning and time while the other represents a quick approximation. It does not matter to Patchworks which method you chose simply that your final road file contains the required fields and information.

Some of the common densification steps involve:

Designing road segments to access all operational blocks in the unit.
- In the extensive method, a road planner could take into account contours, height of land, substrate material and river crossings to chose a path for future road construction for all operational areas.
- In the approximation method, a lattice type of file can be generated based on certain parameters to cover the planning area at a certain density and fill in the holes left by the existing coverage.
Remove segments from exclusion areas such as water bodies, parks and protected areas, private land holdings, etc. The fragment file could be used to identify and select these roadless areas.
Combining new candidate road segments with the existing road segments can cause an unrealistic density in some areas. Eliminate the candidate roads that area within a certain threshold distance of an existing road.

	Tip
	Patchworks provides a tool (in the Data Prep folder of the Application Launcher) to generate a lattice. The lattice generation tool will create an ESRI Generate file based on the parameters filled in the wizard (the extent, the height and width of the squares, rows and columns of lattice and output file name). This file can then be modified to remove any water crossings or roadless areas.

	Important
	It is important to remember that roads added in the densification process do not currently exist and will therefore be built by the model when they are required. It is therefore important add an associated construction cost with these segments. Existing segments will not require a construction cost.