Pavement Deterioration

The design of new pavements in New Zealand and rehabilitation treatments are currently performed in accordance with the Austroads Pavement Design Guide and its New Zealand supplement. New Zealand is also adopting pavement deterioration modeling based on the World Bank HDM models. This paper demonstrates how the modeling of roughness progression can supplement pavement design. It also demonstrates that the long life >50 years of many NZ pavements without significant roughness is not unexpected. It concludes that a combination of deterioration modeling and mechanistic design can be a powerful tool and that the rehabilitation of most of the network is associated with failure other than the classic roughness and rutting.

Results of a study to calibrate the HDM-4 rut depth model to Japan

Adaptation of HDM-4 models for Mediterranean climate

How the HDM-4 pavement deterioration model was calibrated to South Africa

Paper from LVR Conference on HDM calibration to Chile.

Results of pavement performance study in Indonesia and suitability of modelling with HDM-4 approach

Identifies the sensitive input data for pavement deterioration modelling. Although focused on dTIMS, the models were based on HDM

Report describing various techniques for establishing pavement strength and how they were implemented in New Zealand.

Paper describing the calculation of SNP using FWD data

Paper describing the basis for the new SNP in HDM-4

Draft Final Report. The main objective of this Transfund funded research project is to identify the sensitive parameters which will affect the output of the analysis using NZ dTIMS system. This will help the user on deciding which data item should be given higher priority in terms of accuracy level with which data are to be acquired.

Assessment of HDM-4 RDWE models in beta version of HDM-4 software

Report describing how the HDM PDWE model was calibrated to New Zealand.

Memo on different methods for calculating the SNP from FWD data. Includes a workbook which applies the different methods.

Report summarizing a workshop held to address issues in the HDM-4 pavement deterioration modelling.

Report describing issues with the HDM-4 pavement deterioration models and proposed alternatives

Report describing outcome of presentations at 1999 RDWE workshop

The World Bank's Deterioration of Unpaved Roads Model (DETOUR) implements in MS-Excel the road deterioration relationships for unpaved roads of the Highway Design and Maintenance Standards Model (HDM-III), which are the same as the forthcoming Highway Development and Management Model (HDM-4). DETOUR was developed for the World Bank Rural Transport Thematic Group and is designed primarily for engineered unpaved roads, of either gravel or earth surfacing, because the empirical models are based on a variety of such roads. When necessary it is possible to use the relationships also for tracks as a first estimate, but the user needs to be aware that the environmental effects of drainage and rainfall may be poorly represented. For more information regarding roughness and the economic aspects of low volume roads, visit the Design & Appraisal of Rural Transport Infrastructure Web page maintained by the World Bank Rural Transport Thematic Group.

ARRB testing HDM-4's surface dressing model to Australia.

ARRB calibration of HDM-4's surface dressing model to Australia.

This paper presents a proposal for modelling work zones in HDM-4. A worked example of the calculations is also given. It is an update of Bennett (1996) and Bennett (1998) with corrections to several equations and modifications to reflect the current version of the work zone effects software.

Worked Examples of calculating work zone costs.

Paper describing how SNP applied in HDM-4

Report describing the development of the HDM-4 models

Report on HDM calibration

ARRB initial calibration of HDM-4's surface dressing model to Australia.

ARRB evaluation of HDM-4's surface dressing predictions for Australia.

Report by Mike Riley on the examination of the effects of maintenance surfacings on retarding crack initiation and the effect of previous cracking on the performance of the new surfacing.

Realistic prediction of pavement performance is a critical component of asset management. Performance in terms of structural capacity is generally measured by the Adjusted Structural Number (SNP), hence a review has been carried out testing alternative methods for deriving this parameter for unbound granular pavements. Simplified methods may work reasonably well when calibrated to typical local conditions, but they are less likely to provide the same reliability in different regions or with different pavement structures. The rigorous methods (which can be readily applied) are recommended wherever deflection bowl information has been recorded. However, it is important to note that the standard equations are based on isotropic moduli for each layer, rather than anisotropic moduli, which the Austroads Pavement Design Guide has adopted for mechanistic analysis. Typical field measured moduli for unbound granular pavements are presented and appropriate calculation procedures suggested. Calibration or correction of SNP may also be required in a range of circumstances when refining the structural capacity for use in long-term pavement performance prediction. Where representative benchmark sites are set up and actual performance is monitored, appropriate calibration factors, based on specific modes of distress can be developed. These result in effective SNP values for a given network, giving due regard to the local range of materials and construction techniques.

Report on pavement deterioration models approached for Indonesia's low-volume Kabupaten roads.

Tentative model forms for structural cracking

Report describing how the FICEM concrete models were incorporated into HDM-4

Working paper from HDM-4 study on the impact of seals and thin overlays on crack initiation and progression.

Meeting Minutes. Objective of the meeting was to resolve the outstanding techinical issues with respect to Road Deterioration and Work Effects modelling in HDM-4.

This is the second paper reviewing the Road Deterioration and Maintenance Effects (RDME) relationships proposed for HDM-4.

This paper details an initial review of the Final Report. The review focuses on the first eight chapters which cover the proposed road deterioration relationships for HDM-4.

Paper looking at the HDM probabilistic cracking model and LTPP data.

Calculation of adjusted SNP

Memo describing modifications to HDM-4 densification model

Original specification and associated files for how HDM-4 handles maintenance works effects.

Program for predicting pavement deterioration rates

Memo describing proposed HDM-4 transverse thermal cracking model

TRB paper describing analysis of LTPP data with HDM modelling approach

Paper describing how works interventions would be handled in HDM-4

Preliminary recommendations for defining the effects of works in HDM-4

Report on road deterioration and maintenance effects modelling.

Background to HDM-4 Rut Depth Modelling

Review of how the HDM-III RDME model was applied in different studies

This report is the original NDLI report describing the HDM-4 pavement deterioration and works effects models. Some of the models were refined, but it provides a lot of the background to the final HDM-4 models. It also includes models that were not included in HDM-4, such as for block pavements.

A review of how HDM-III was used in studies in different countries.

This major technical document describes the overarching framework and modeling algorithms for Road Deterioration and Works Effects (RD&WE) in HDM-4. Designed to simulate the physical performance of road pavements over multi-year analysis periods, the model covers a broad range of pavement types including flexible bituminous pavements, rigid concrete pavements, unpaved gravel roads, and block paving. Mathematical equations govern the initiation and progression of key distress mechanisms: structural cracking, raveling, potholing, rutting, edge break, and surface roughness progression (measured in IRI). These distress models account for pavement structural strength (Modified Structural Number), cumulative heavy vehicle traffic loading (Equivalent Standard Axles), environmental climate factors (rainfall, temperature variations), and subgrade soil strength. Additionally, the paper details the Works Effects sub-model, which simulates the physical impact and structural restoration achieved by various maintenance interventions, such as patch repair, crack sealing, surface dressing, asphalt overlays, and full reconstruction. The integrated RD&WE framework allows road managers to optimize life-cycle maintenance strategies, establish condition-responsive work programs, and evaluate the long-term economic trade-offs between initial construction quality and routine maintenance funding. Overall, the report emphasizes rigorous empirical validation, standardized data acquisition protocols, and modular integration into the broader Highway Development and Management analytical engine. By combining physical principles with statistical calibration across international trial sites, this working paper provides a robust theoretical and practical baseline for highway authorities to evaluate long-term infrastructure policy options, allocate maintenance budgets efficiently, and maximize economic returns across regional and national road networks.

 

Definitions of pavement ages in HDM-4

Default parameters for when using aggregate data inputs in HDM-4

Memo on traffic as opposed to time based models for HDM-4

Proceedings from a workshop to discuss issues with regard to pavement modelling for cold (freezing) climates.

Simplified generalized pavement deterioration models.

HDM-III reference manual Volume 5

Bill Paterson's book describing the development of the pavement deterioration models for HDM-III, which are the basis for HDM-4's models.