Road Sections
Overview
Section titled “Overview”Defining the Road Network
Section titled “Defining the Road Network”HDM5 evaluates the physical, technical, and economic viability of specific road investment alternatives (such as maintenance, overlays, widening, geometric realignment, or new construction) over a multi-year life cycle.
Road Sections
Section titled “Road Sections”The homogeneous Road Section is the fundamental building block for all modelling in HDM5. A road section is an identifiable length of existing road over which key physical, geometric, structural, traffic, and environmental characteristics are reasonably uniform. Road sections may also start and end at intersections, dead ends or locations where traffic volumes, alignment or administrative boundaries change significantly.
Defining Road Sections
Section titled “Defining Road Sections”Road Sections represent the existing road network. Define those existing Road Sections using the Road Network screen, by:
- Adding new Road Sections manually
- Importing Road Sections from an external file
- Importing Road Sections from another HDM5 analysis – this is particularly useful for large networks with multiple sections
GIS (optional)
Section titled “GIS (optional)”Define mapping for Road Sections in the Geographic Information System (GIS). This allows thematic mapping throughout HDM5 (for example for road condition, traffic volumes, traffic growth sets), assignment of key modelling parameters (such as climate zones, road deterioration sets), and mapping of the results of modelling and economic analysis.
Key Section Data
Section titled “Key Section Data”Enter section data under the following tabs/categories:
- Definition / General Attributes: Unique Section ID and name, section length, and surface class.
- Section Characteristics: Road Class, Calibration Set, Pavement Type, Surface Type, Base Type, Carriageway Width, Shoulder Width, Flow Direction
- Geometry: Horizontal Terrain, Vertical Terrain, Acceleration Noise (Adral), Speed Limit data, Altitude
- Condition at the Start of the Analysis: These represent the condition of the section at the start of the analysis. The characteristics available are dependent on the Surface Class. For Bituminous Pavements, they include Roughness, Cracking, Ravelling, Potholes, Edge Break, Rutting, Texture Depth, and Drainage Condition.
- Pavement: These represent the pavement type, material type, recent and previous surface thicknesses, years of last rehabilitation and preventive maintenance works, the structural number, California Bearing Ratio (CBR).
- Speed Reduction Factors: various parameters used to model speed depending on road condition.
- Other Attributes: Number of Lanes.
New Construction Sections
Section titled “New Construction Sections”New Construction Sections represent new sections in the road network that will be modelled under an improvement project. Define New Construction Sections and their attributes under Work Standards. Their attributes are similar to those for existing road sections.
See Also
Section titled “See Also”- Geographic Information System
- New Construction Sections
- Work Standards