About Section Merging
By default, Treatments generated with the Analysis module do not cross Network Section boundaries. To enable Treatments to be generated for adjoining Sections, Horizons includes a Section Merge feature that allows adjacent Sections to be merged into Super-sections and stored in a Layer. The Layer can then be used as input in Analysis. Horizons will support section merge rules based on your Network’s attributes to more easily merge sections in context with your Network data. See Using a Super-section Layer in a Treatment Set.
Super-sections are continuous linear merges of adjoining Sections without any junctions or loops.
You can generate a Super-section Layer by specifying each Section individually via a grouping file (Group Merge Mode). Or the Layer can be generated automatically according to a set of connection rules (Non-Group Merge Mode). Or you can use a hybrid of both methods (Group & Non-Group Merge Mode).
There are three merge modes available for creating Super-section Layers:
Merge only within specified groups
You import a grouping file that specifies the Sections to merge together along with a set of connection rules that only merge within specified groups. This is sometimes referred to as a Group Merge.
You can use merge only within specified groups on an existing Network Layer to group by road name or number, for example.
To Define a merge only within specified groups
Merge with no special grouping rules
The system attempts to join all Sections in the Network according to a set of connection rules unlinked to groups. This is sometimes referred to as a Non-Group Merge.
To Define a merge without special grouping rules
Merge within and around groups
The merge process joins Sections using the merge only within specified groups connection rules first. Then connections for Sections that have ends within the maximum distance but do not pass the merge only within specified groups rules are attempted using the merge with no special grouping rules process. This may also be referred to as a Group and Non-Group Merge.
This is useful if merge with no special grouping rules mode works for most Sections but a few Sections need a manual override using a grouping file.