Keywords used: HDM-4 software, pavement management, highway development, road asset management, economic appraisal, vehicle operating costs, life-cycle analysis, road deterioration model.
| Data Layer | Key Inputs | Typical Source | | :--- | :--- | :--- | | | Road ID, length, width, surface type, traffic direction | PMS database, GIS | | Pavement Condition | Initial IRI, cracking %, rut depth (mm) | Laser profilometer, manual surveys | | Traffic | AADT, vehicle class distribution (car, bus, 2-axle truck, articulated truck), annual growth rate, ESA/vehicle | Weigh-in-motion (WIM), traffic counts | | Climate | Mean annual rainfall, temperature, Thornthwaite moisture index | Weather stations, satellite reanalysis | | Economics | VOC per vehicle type, value of time, discount rate (typical 12% for developing nations), construction unit costs | National statistics, tender data | hdm-4 software
: After installation, run the software as an administrator and follow the registration utility steps to obtain and enter an Unlock Code 2. Core Analytical Framework HDM-4 facilitates three main levels of analysis: Project Analysis It is used by: In the past, road
HDM-4 is a global standard. It is used by: Annual rainfall 1200 mm
In the past, road maintenance decisions were often political or reactive—fixing the road only when it became unbearable to drive on. HDM-4 changes the game by introducing .
A 50 km unpaved road in a developing country with 200 vehicles/day (20% heavy trucks). Annual rainfall 1200 mm. Current IRI = 12 m/km.