Applications

This study develops a stochastic pavement LCCA framework to account for the effects of such uncertainties on climate change-induced pavement life cycle cost. This is achieved by integrating a sensitivity analysis methodology and Monte Carlo simulation. To demonstrate the applicability of the framework case studies are performed for standard interstate and standard primary road pavement sections in four climate zones in the United States under a high climate change Representative Concentration Pathway (RCP8.5) for four different periods between 1981 and 2100. The results show that pavement maintenance, end-of-life (EOL), and transportation costs are most affected by climate change. To assess climate change-induced pavement costs more accurately, it is important to improve the accuracy of gasoline, diesel, and hot mix asphalt (HMA) unit costs, as they are the most sensitive input to the pavement LCCA model.

Paper describing the development of optimal pavement maintenance strategies.

This study aims to compare the results of stochastic and deterministic models and their corresponding optimal M&R actions considering different budget and deterioration rate uncertainty scenarios. Moreover, the impacts of uncertainty on network’s scale are investigated. Therefore, this study applies Multi-Stage stochastic programming to model the uncertainty of these parameters in pavement M&R optimization. A new approach is proposed to investigate the effects of different uncertainty cases on the mentioned problem. Moreover, two pavement networks, including a large-scale and a small-scale, are utilized to evaluate the role of network size in the optimal solution to the pavement M&R optimization in the uncertainty conditions. Due to the high complexity of the large-scale M&R problem, Progressive Hedging Algorithm as an effective decomposition technique is applied. Three different uncertainty cases, including low, medium, and high are considered for the deterioration rate. Furthermore, two scenarios are taken into account for the budget: low reduction and high reduction. The results show that the probability of selecting preventive maintenance in the optimal M&R plan is increased by increasing the severity of uncertainty cases. Therefore, preventive maintenance is the most effective pavement treatment to reduce the adverse effects of budget and pavement deterioration uncertainty.

India’s growing demand for adequate maintenance and upkeep of the world's second-largest road network of 5.89 million kilometers is a major problem for road administrators and policymakers. To address the issue of proper upkeep of road networks, many countries have implemented a robust pavement management system (PMS) to handle the tasks related to pavement maintenance and management. The Highway Development and Management (HDM-4) system is widely used as a tool for highway investment and maintenance planning and programming. The broad objective of this study is to develop pavement deterioration models for cracking, ravelling, potholes, rut depth, and edge break using non-linear regression techniques in MATLAB and compare them with the models present in HDM-4 and observed deteriorations for their effectiveness. The deterioration models for urban and rural pavement sections have been developed based on the large volume of field data collected in the Jaipur district of Rajasthan State using automated as well as manual methods of field evaluation. These sections were continuously monitored for 5 years for the pavement surface condition data. The validity of these models and calibrated HDM-4 models was assessed by examining the distress predictions generated by the regression models and calibrated deterioration models to the distress observed on the selected pavement sections. The proposed pavement deterioration models and the calibrated HDM-4 models are likely to apply to other developing nations with comparable traffic patterns, soil types, meteorological conditions, terrain kinds, and pavement composition as well.

Due to the increase in urbanization and industrial development in India, there has been substantial traffic on the existing roads. This impact had increased public demand for good quality roads with better maintenance and high serviceability. Further, catastrophic events like flooding can cause damage to pavements, especially in those with granular base layers and thin asphalt mix surface layers. The degree of damage relies upon the vulnerability of the pavement to the entrance of surface water, the measure of water immersion, and the drainage quality of the pavement. The extensive literature review found limited studies on the post-flood maintenance strategy for low-volume roads by considering flood resilience. In the present scenario of changing climatic conditions, it is necessary to conduct a study on the post-flood maintenance strategy of low-volume rural roads in India. This study focuses on an approach to developing post-flood maintenance and rehabilitation strategies for flood-affected low-volume roads. Ten road stretches adversely affected by the flood were selected to fulfil the aim of the study. The post-flood maintenance strategy was determined based on the Pavement Condition Index (PCI) and deflection-based pavement performance with flood resiliency of pavement materials and budget constraints. The extensive data analysis revealed that the pavement with a cement-treated base or subbase has a longer service life and less Net Present Value (NPV) than all other alternatives. NPV is 30 to 45 for rehabilitation and 52 to 55 for reconstruction, lower than other alternatives considered in the study.

The aim of the study describes the adaptation of World Bank’s Highway Development and Management commonly known as (HDM-4) for calibration of HDM-4 pavement deterioration models for selected pavement sections w.r.t local conditions over time with traffic. For this study road condition surveys along with different distresses measurement was done for 16 urban road sections in Patiala City and base data, structural & functional evaluation is performed on two stretches. It includes, Optimum Maintenance and Rehabilitation (M&R) Strategy along with Prioritization for all the selected road sections.

As they do not have a sealant coating, forest roads are more susceptible to degradation and traffic obstruction, requiring better construction and maintenance attention. This study aimed to assess the performance of maintenance carried out on unpaved roads in technical, economic, and socio-environmental scopes by application of the Highway Development & Management Model (HDM-4) and to show the best project proposals. The analyses consisted of inputting the HDM-4 with the characteristic data of roads, of and the maintenance to be adopted and the type of used vehicle. The association of this information made it possible to envision scenarios that consider either the replacement or non-replacement of gravel materials on the roads as a methodology. For management without gravel replacement, the most effective scenario was that of roads with gravel under the bed, located in a tropical climate, with flat features and 90 kilometers in length, initial thickness of 175 mm of gravel, high volume of traffic, and subject high-level maintenance at 30-day intervals. For the management with gravel replacement, the ideal scenario was that of roads with gravel under the bed, located in a temperate climate, on rolling terrain and 30 kilometers long, initial thickness of 175 mm of gravel, high traffic intensity, and subjected to high-level maintenance every 30 days. High-level maintenance was the best option for maximizing the quality of the roads and providing the best total net benefit, lowest gas emission rates, least fuel, and tire consumption, and adequate pavement condition by the end of the project.

In this paper the Non-Motorized Traffic (NTM) model of the HDM-4 (Highway Development and Management) is applied for the analysis of different alterna1ves for bicycle lanes, evalua1ng aspects such as current and potenial cyclists demand, operation speed, capital costs and economic profile of bicycle users.

This research evaluated the relationship between the road-generated revenue (RGR) and its allocation towards the national road network expenditure and related these to international standards. The findings indicate that the Road Fund Administration (RFA) possesses high transparency in allocating RGR towards the preservation of the road network. This places Namibia among countries with high dedication of 80% and above towards road expenditure, together with the United States of America (USA) and Switzerland when compared to international standards. While revenue generated from road users are highly allocated to the preservation of the road network (0.96 ratio), a wide gap remains between the required funds and resources available for road expenditure. Financing for road expenditure was found to be a dilemma facing many developing countries, where revenue from road users does not cover the total road costs due to limited capacity and economics of use. Additional funding sources are therefore required to fund these deficits. The research also demonstrated the applicability of the Highway Development and Management (HDM-4) model, to determine the Marginal External Costs (MEC) of road use. The results indicate that heavy vehicles impose the highest costs in terms of infrastructure damage and environmental costs when using the network. When applying marginal costing, the results indicate that heavy vehicles contribute approximately 98% (district road), 97% (main road), and approximately 98% (trunk road) in terms of external costs when using the respective network. Overall, light vehicles contribute the most to congestion and accidents costs when using the national road network. Although the results presented the national road network to be congestion free, relatively low congestion was traced on the trunk road, thus increasing the overall cost contribution for light vehicles from 2% (district road) and 3% (main road) to approximately 19% when using the truck road network. The findings indicate that motorists impose some externalities when using the road network and it would make economic sense to internalise such costs to road users. The research further assessed the implications of setting Road User Charges (RUC) at the Short-Run Marginal Costs (SRMC) of road use. The results indicate that setting RUC equal to correct prices leads to an estimated road funding deficit of N$5 062 746 on the sampled trunk road. These findings indicate that a marginal pricing approach in the Namibian context (expansive road network serving few users) might not necessarily raise the revenue required for the investment and maintenance of the network. This situation calls for an alternative approach to marginal pricing. In exploring the second-best RUC suitable to the Namibian funding circumstances, this study explored what Namibia could learn from other countries with expansive road networks such as Australia and New Zealand. The findings presented the efforts Namibia that has made in terms of policy formulation and noteworthy institutional frameworks, which have made Namibia the leading country in sub-Saharan Africa in terms of road-quality rankings. However, Namibia needs to embrace technologies towards charging vehicles per kilometre. The existing Mass Distance Charges (MDC) attempted to solve the challenges associated with charging heavy vehicles according to distance travelled; however, the current MDC is a blunt instrument that does not adjust charges according to weight, time, and location. Reforming the current system with the focus on distinguishing suitable charges for light and heavy vehicles to account for their use of the road network per vehicle per kilometre according to time and location is something that Namibia could learn from Australia and New Zealand. Collaborating efforts from both the public and private sectors could be another step toward a road financing solution.

Roadway is one of the most crucial transportation modes to cater to inland movement within a country. The agency mandate is to design, construct, and maintain the road to sustain the traffic up to its design life without further strengthening. However, some
factors are affecting the performance of the pavement. Most pavements start to show some traces of deterioration after construction and opening to traffic, but once neglected, the distress portions would be aggravated with corresponding increasing maintenance cost. Thus, the road's maintenance has to be carried out at the place, right schedule, right quality, and at the least cost. Since there are different maintenance alternatives, the best strategy has to be chosen following the road's condition and the severity of the damage. To select the best maintenance alternative, calculations on the pavement layer's property are performed. The Highway Development and Management (HDM-4) tool can do such measures to help decide which option is the best by evaluating the economic and structural conditions. This paper contains two significant areas that are studied. First, it was assessed the procedures followed by the city's road authority to develop the appropriate road maintenance strategies. Questionnaire surveys and interviews are used to collect information from the city's road maintenance departments. Second, the project analysis was performed for structural and economic comparison of different maintenance alternatives using HDM-4. In the analyses, three selected road segments are considered and collected important input data like road condition data, road network data, vehicle fleet data, estimated AADT, and International Roughness Index (IRI). There were five maintenance alternatives have been defined, and proposed maintenance alternatives are compared. The selection is based on the deteriorated pavement, which showed the average roughness for every section of the road network, considering an analysis period of 20 years and cost stream ranking for their Net Present Value and IRR. Results indicated that using a mill and replace, and
routine maintenance schedule for the selected road networks is economically viable and structurally significant. Hence, the city's road authority is recommended to apply the different maintenance strategies, providing an economical and better performance for the city's road network.

Road surfacing policy is among the most influential mechanisms available to road authorities to alleviate budget and resource constraints and to enhance their level of public service delivery. Given that gravel roads constitute 73.6% of the South African road network, this paper identifies cost-effective surface solutions for these roads under different local conditions experienced across South Africa. Gravel and cape seals, which are selected as a potential light bituminous seal alternative to gravel, are explored using a Cobb-Douglas production function that represents their major inputs: capital; labour; basic materials; fuel; and other inputs. The respective factor intensities for the production functions are based on 2018 road construction and maintenance unit cost data for South Africa. The relative costeffectiveness of the alternative road surfaces is evaluated through a lifecycle cost analysis (LCCA), with the production function parameters stress tested according to cost variances caused by actual environmental and market conditions. Road user and road accident costs are added as additional LCCA stress tests to extend the study beyond road authority costs. The results indicate that the dominant strategy, in terms of cost-effectiveness and welfare, is for South African road authorities to seal those gravel roads worth maintaining at a rate possible within budget limitations.

PhD Dissertation presenting an innovative environmental-based decision-support model for planning highway construction programs. The model is developed in three main parts that are designed to: (1) model total vehicle fuel consumption and public benefits/costs of traveling on transportation networks; (2) evaluate the economic and environmental impacts of highway rehabilitation efforts; and vi (3) develop a multi-objective optimization model to identify and evaluate highway rehabilitation program(s) that are capable of simultaneously minimizing environmental impact and maximizing public benefits of rehabilitation decisions.

 

 

The World Bank Highway Development and Management (HDM-4) tool has been used extensively for the management of road networks, particularly in developing countries. The paper describes the application of HDM-4 model for local roads in Bosnia and Herzegovina (BiH), in the Herzegovina-Neretva Canton (HNC). The HDM-4 study was performed with the aim to define road works program and investment priorities by analyzing impacts of different budgets on future network condition. The 396 km-long HNC road network consists of 13 roads that are either graveled or paved. A large part of these roads do not have sufficient pavement width. This road network is in relatively poor condition due to its age (the average age is over 30 years) and limited spending on maintenance in the past. Only a small percentage of the network has been reconstructed in recent years. The Average Annual Daily Traffic (AADT) has a wide range, and varies from 27 to 12735 vpd. The major challenge in the study was to obtain HDM-4 input data with limited resources, since usually this task requires extensive investigations. In addition to inventory data, it is necessary to define the condition of the road network, traffic volume, traffic data, etc. Road geometry data were obtained from previous studies and project documentations. The IRI data were taken from the earlier surveys or estimated where no data were available. Other parameters were obtained by field tests. Traffic data were available from regular network traffic counts. After analyzing the parameters, the network was divided into 65 homogeneous sections, based on the AADT and road condition (IRI and other parameters) classes. HDM-4 program analysis was performed for a period of 30 years. Due to very low traffic loading and relatively large investment needed for improvement, for majority of sections a negative NPV and IRR were obtained for maintenance alternatives other than routine maintenance, and for significant number of sections they were on the verge. Out of 65 homogeneous sections, only 29 sections proved cost-effective (NPV/CAP ratio is positive).   The implementation of developed road work programs would result in a substantial improvement of the overall network condition. The IRI of paved road network would change from current value of 4.5 m/km to 4.0 m/km and 3.7 m/km for budget levels of 2.0 and 3.0 mill. BAM after five years. The better road network condition would also result in improved traffic safety, social and economic impacts, since many of these roads are crucial links in the HNC.

A study has been carried out on Patiala city road network to provide a powerful system for the analysis of pavement management and investment strategies for the maintenance of the huge urban road network. TheHighway Development and Management-4 (HDM-4) software has been used for strategy and program analysis of 52 road sections of Patiala city, out of which 5 manageable pavement sections on the basis of various characteristics are discussed in detail. The HDM-4 tool provides the deterministic approach in data input and processing also utilizes data on existing road condition, traffic volume and composition to predict road.

Strategic analysis can be used to analyze the whole selected network and to prepare assessment of requirements for development costs and road preservation according to different budget scenarios and in different time intervals. Optimal strategy for Azerbaijan was determined by comparing possible maintenance works for each road segment, depending on current pavement condition and traffic volume. Analysis without budget limitations determined optimal solution for each road class, which implies the solution that minimizes total management costs for the roads and user.

To manage a road network it is vital to have an Asset Management Plan that is consistent and gains the confidence of users and higher management. Muswellbrook Shire Council in Australia is using the Highway Development and Management (HDM-4) as its Pavement Management System (PMS) which is the basis of the Asset Management Plan. Some inconsistencies were observed earlier between HDM-4 results and field. It is essential getting consistent HDM-4 results. The current paper has tried to rectify treatment intervention levels through several HDM-4 runs, site visits and engineering judgment for obtaining sound results. It is observed that treatment decision matrix and data quality are vital HDM-4 inputs. The new and realistic compound standards with treatment intervention criteria have been proposed for urban and rural roads. As a result, the road network is maintained at 5.6 IRI (International Roughness Index, unit is m/km) with A$2 millions ($2 m) per year using ‘minimise cost at target IRI’ optimisation objective. It is recommended to verify HDM-4 results at site for consistency as there is a time gap between data collection and obtaining analysis results. This is a useful analysis for the asset managers, engineers and planners for obtaining justifiable asset management plan, works program and long-term strategy. Finally, it is suggested that each road authority should have set optimum maintenance standards and strategies derived using HDM-4 in managing their assets.

Monitoring of pavement state as a basis for economic regulation of greenhouse gases emissions. Road complex which includes a road network with traffic, road services, car repair businesses, and enterprises for the production of fuels and materials for the repair of roads, is an important source of environmental pollution, and the degree of contamination depends on the quality of the road pavement. The present research is aimed to find the interaction between the amount of emissions into the environment from whole road complex and condition of road cover, on creation of a simplified method of determining economic damage from environmental pollution at the road operation and to develop basic mechanism of the economic impact on road services at excess emissions. According to the results of computer experiments mathematical relations of complex road emissions from the evenness of road pavement were obtained. Worked out method of greenhouse (and other) emission inventory permits to determine the total amount of emissions and to identify excess emissions relative to some acceptable level. Definition of economic damage of environmental pollution during road operation can be the basis for determining the amount of ban impositions on road service.

Paper on application of HDM-4 for treatment selection in Tennessee. 

Abstract.Pavement maintenance is one of the major issues of public agencies. Insufficient investment or inefficient maintenance strategies lead to high economic expenses in the long-term.Under budgetary restrictions,the optimal allocation of resources becomes a crucial aspect.Two traditional approaches (sequential and holistic) and four classes of optimization methods (selection based on ranking, mathematical optimization, near-optimization and other methods) have been applied to solve this problem. They vary on the number of alternatives considered and how the selection process is performed. Therefore, a previous understanding of the problem is mandatory to identify the most suitable approach and method for a particular network. This study aims to assist highway agencies, researchers and practitioners on when and how to apply available methods based on a comparative analysis of the current state of the practice.Holistic approach tackles the problem considering the overall network condition; while the sequential approach is easier to implement and understand, but may lead to solutions far from optimal. Scenarios defining the suitability of these approaches are defined. Finally, an iterative approach gathering the advantages of traditional approaches is proposed an applied in a case study. The proposed approach considers the overall network condition in a simpler and more intuitively manner than with a holistic approach.

The Namibian Road Management System (RMS) has been in existence since the late 1980’s and can be used not only as a model for Africa and developing countries, but for the international community as well. Namibia went through a major road sector restructuring process for the Ministry of Works, Transport and Communications (MWTC) to form three new entities: the Roads Authority (RA), Road Fund Administration (RFA), and Roads Contractor Company (RCC). The RMS was included in the Roads Authority Act and plays a vital role in managing the countries road
network. This paper will look at how the RMS of Namibia was developed and is being used in contributing to the management of the road network consisting of 45,645 km. Experiences gained from the strategic output of the World Bank’s model (HDM-4) and the integration of the model with the RMS are also evaluated.

Taiwan Highway System experiences successively investment of few decades in government. After the first national highway-Chung Shan, the Second national highway, twelve west to east freeway and western seaside freeway go to operation, the road network is gradually complete. The road engineering changes the style from new construction to maintenance management. In recent years, because the government public construction budget reduce year by year, so road agencies should be emphasizing facilities management and enhancing construction performance that keeping highway transits service quality with the constraints of budget limitations. World Bank carries on a series of project researches to the road in 1968 and develops the related evaluation module. In HDM-4, it provides the extensive module application and explicit method in the stages such as planning, programming, preparation and operation etc. It provides a reference that road agencies carry on related decision. HDM-4 provide user to adjusting with different region parameter such as weather, environment...etc. So this tool can be applicable to more widespread region. When the related pavement maintenance systems are not satisfactory, how to use the international identify tool help Taiwans highway maintenance management. It is very interesting and workable research. We use HDM-4 to collect and analyze Guan-Xi regions Highway No.3 network data, traffic characteristic and cost related information. Through this knowledge, we can adjust the HDM-4s parameter to suit Taiwans condition. Besides, we review technical literature and experts experience to determine on maintenance alternates. We use adjusted mode with real highway budget to determine the threshold of routine and period maintenance. Considering maintenance cost, user cost and highway economy to decide suitable threshold. Finally, base on the best maintenance strategies to explain the relation between maintenance budget and performance. Base on this result, we can determine the budget allotting criteria to reach the biggest economy benefit of the resource.

Pavements which are left to deteriorate without timely maintenance treatments
are likely to require major rehabilitation and reconstruction much sooner than those which
are properly maintained. In developing countries like India, where the traffic growth and axle
loading is growing at logarithmic scale, deterioration of highways is very fast. This increased
traffic demands for multilane highways with proper maintenance time to time. During the
process of road network maintenance and rehabilitation, road authorities strive to select an
optimum maintenance strategy from a number of alternatives. This selection may be obtained
only through a realistic approach. An economically acceptable maintenance strategy may
be selected among a number of maintenance alternatives. It can be done by calculating and
comparing the various maintenance and rehabilitation (M&R) alternatives with the help of
Highway Development and Management tool (HDM-4). This available technology and tool
that makes implementing an effective pavement rehabilitation program feasible, is globally
accepted. This paper specifically addresses flexible pavement, including the multilane highways
from northern region of India. Study involves the data collection and selecting the optimum
M&R strategy by using programme analysis component of HDM-4 for selected road sections.
It is expected that the information contained in this paper would be useful for developing
optimum maintenance management strategy for multilane highways.

The UK Department for Transport is concerned to know that long-term investments in maintenance of local roads arecontributing optimally to the UK economy, and that road maintenance funds are distributed equitably and provide value for money for the taxpayer. This quest can be accomplished by using decision support tools capable of predicting the long-term performance and costs of maintenance of the UK local road network. This paper describes the development of the World Bank’s highway development and management model HDM-4 for use by the Department for Transport at the strategic level. This involved adaptation and calibration of HDM-4 to accurately model pavement performance and road user effects in England, linking HDM-4 with the existing database system used by the Department for Transport in order to facilitate strategic level analysis and investigation of road investment choices, and conducting a trial strategy analysis of the English local road network to quantify long-term maintenance needs and assess the effects of different maintenance funding levels on the condition of the network and costs to road users. The strategic analysis derived optimal capital and recurrent maintenance needs to clear existing maintenance backlogs and thereafter keep the road network in good condition on a sustainable basis.

Option evaluation systems (OESs) have been widely recognized as a powerful means for investigating optimal pavement preservation strategies (OPPSs) of road networks in various situations. OESs, however, entail exogenously specified alternatives of pavement preservation. A combined optimization- simulation methodology has been generalized (called GCOSM) for finding optimal maintenance strategies without relying on user specified options in OESs, taking into account of various treatments including resealing, overlay and reconstruction. Based on GCOSM, the objective of the paper is to propose an approach to investigating OPPSs for a national road network in a systematic manner. The HDM-4 system is employed as an OES in the study for Vietnamese national road network. The findings may provide a guideline for highway agencies in better applying the appropriate maintenance policies based on site surveys in terms of pavement conditions and traffic situations with regard in saving the total transport costs to society.

In this case study, the City of Abbotsford’s pavement management system is used to demonstrate the use of pavement deterioration and maintenance cost forecasting models, which makes it possible to perform a complete life cycle cost analysis on pavements. There are usually many alternative feasible strategies for preserving a given pavement segment. Each alternative strategy can include one or more successive treatments. Each alternative strategy is also associated with different routine preservation and maintenance costs. All of the theoretically possible strategies are generated with analysis software and can then be optimized and prioritized under various budget scenarios. This allows for the rigorous economic justification of comprehensive programs that minimize the net present value costs and maintain pavement networks in a sustainable manner. Moreover, the City uses this system to arrive at network funding levels which are not only saving it citizens millions of dollars in direct and indirect costs but is also reducing the City’s GHG gasses.

The study shows that not only do “Good Roads Cost Less” in terms of direct maintenance and rehabilitation cost, they also significantly reduce road user costs and overall Green House Gas emissions.

Very interesting paper on the application of fuzzy math when characterizing roughness and the impact of this on outputs from the RED model

Option evaluation systems (OESs) have been extensively used as an effective means to support decision-making on investment and management of road asset in both developed and developing countries over the last four decades. When carrying out the strategy analysis using OESs with dynamic sectioning (called SDS), a nationwide network is typically subdivided into several sub-networks due to administrative or technical needs. However, techniques for doing SDS in such a case have not been well developed. Therefore, the objective of the paper is to present a comprehensive procedure to carry out the SDS for a nationwide road network including sound trade-off analyses of all constituent sub-networks. Although the Highway Development and Management System (HDM-4) is used as an OES in the case study in this paper, the proposed procedure is general enough to allow almost any OESs.

 

Strategy and program analyses using option evaluation systems (OESs) such as HDM-4 have been powerfully used for exercising pavement management planning at the network level. Theoretically, there is no distinction between strategy analysis with dynamic sectioning (SDS) and program analysis, and the results of SDS analysis may be used directly to identify the most appropriate single or rolling multiyear work programs and contract packages for individual sections of a road network or sub-networks. However, techniques for doing such an analysis have not been well presented. Therefore, the objective of this paper is to provide a systematic procedure as a guideline for identifying single or rolling multiyear work programs under given budget constraints where the SDS is utilized. The presented procedure employs HDM-4 as an OES for the purpose of demonstration, but it is deemed to allow almost any OESs.

Highly Recommended: Rodrigo Archondo-Callao from the World Bank was involved in developing HDM-III and HDM-4 and has participated in the application of the models in many countries. 

This technical note presents his experiences in using HDM for road network strategic planning evaluations in developing countries, with the objective of providing recommendations and tools to the readers who are involved in strategic planning activities. The purpose of the evaluations, the methodology itself, the input requirements, the challenges, and the presentation of results to decision makers are each reviewed in turn.

The methodology described here attempts to take advantage of all the capabilities of HDM-4, giving due attention to its limitations, and produce usable results. The examples provided represent actual HDM-4 inputs and results obtained from many HDM-4 studies in developing countries in recent years; they were selected from different studies to best illustrate a given evaluation step, but do not otherwise represent a pattern or relationship.

Roads and Highways Department (RHD) of Bangladesh does not have appropriate maintenance standards to maintain the road network efficiently. Therefore, a study was conducted to improve some important aspects of Pavement Management System (PMS) in Bangladesh, which dealt with analysis of road database of RHD for reliability, development of treatment intervention criteria and optimum maintenance standards using the Highway Development and Management (HDM-4) model. This paper discusses deriving optimum pavement maintenance standards using the HDM-4. All the road maintenance treatments used in Bangladesh were considered to
determine optimum intervention levels for each treatment using different sections optimisation technique. The study divided the whole RHD road network into 48 groups of road based on surface type, traffic volume and pavement width to determine the optimum maintenance standard for each road group. It was observed that the derived optimum maintenance standards could be used for future decision-making purposes, as they were within the zones of optimum maintenance standards. Detail examples in deriving optimum pavement maintenance standards were given in this paper.

This study used the HDM-4 software to test the average annual daily traffic (AADT) and equivalent single axle load (ESAL) levels appropriate as criteria for selecting the application of bituminous surface treatments (BST) to Washington State DOT pavements. It verified the feasibility of using BSTs to maintain pavements with higher traffic levels than have been applied in the past. It also determined the validity of alternating the application of BST resurfacings and 45-mm hot mix asphalt overlays. In addition, the research estimated the impacts that increased use of BST surfaces would have on the performance of the state-owned route system.
The basic recommendations are as follows:
• ADT of up to 2,000: Apply BSTs unless they are specifically exempted (such as paving through cities, limited BST routes, etc.).
• ADT of 2,000 to 4,000: Apply a combination of BST and HMA overlays used interchangeably, depending upon pavement condition. Exemptions are allowed for paving through cities, limited BST routes, etc.
• ADT of greater than 4,000: Apply HMA overlays.

The paper deals with analyses of optimal procedure and methodology of motorway maintenance strategy in Serbia. The technical-economic analyses have been done using HDM-4 model with necessary calibration of the model for local conditions. According to the system of references for the motorway road network of Republic of Serbia, analysis implied 57 motorway sections divided into four typical classes, considering various motorway maintenance strategies. Proposed methodology is verified through analyses of pavement rehabilitation needs on case study section of motorway E-75, Novi Sad &ndash, Belgrade.

The paper deals with analyses of optimal procedure and methodology of motorway maintenance strategy in Serbia. The technical-economic analyses have been done using HDM-4 model with necessary calibration of the model for local conditions. According to the system of references for the motorway road network of Republic of Serbia, analysis implied 57 motorway sections divided into four typical classes, considering various motorway maintenance strategies. Proposed methodology is verified through analyses of pavement rehabilitation needs on case study section of motorway E-75, Novi Sad –, Belgrade.

This project performed extensive study and systematic research on the application of the Highway Development and Management system (HDM-4) to the Washington State Department of Transportation (WSDOT) highway system. Data processing, testing, calibration, and analysis were executed to provide the WSDOT with a new budget planning tool. HDM-4 flexible pavement deterioration models were calibrated with the assistance of the Washington State Pavement Management System. A method to calibrate concrete pavement deterioration models is proposed. This research also explored the application of HDM-4 analysis at the project, program, and strategic levels. The applications include prediction of pavement conditions during a defined analysis period, calculation of required budgets for optimal pavement conditions and maximum economic indicators, establishment of optimized work programs under varying levels of constrained budgets, and other applications for WSDOT.

Economically justified threshold values for maintenance interventions on German Federal Motorways. [In German]

Excellent report describing the Cambodian \'Location Referencing and Condition Study\'. This study undertook a network survey of Cambodia\'s road network and put in place a road management system. Report covers all aspects of the project. There are other reports on data collection procedures and HDM-4 calibration available.

Report describing how HDM-4 was configured for use in Cambodia.

This paper presents a case study that illustrates how to address various issues involved in conducting a strategy analysis that have not been well documented in the Highway Development and Management Series Books. It is deemed to be a useful training material for the upcoming HDM-4 courses to be held in Albania and Bosnia and Herzegovina under the sponsorship of the World Bank.

Details on the modelling approach in HDM-4 and the Swedish PMS

Effects of Less-than-Optimal Maintenance

An Analysis Using HDM-4

Paper on optimizing road investments with HDM.

Executive summary describing MWH Cambodia LRCS survey.

Report by MWH on calibration procedures used in Cambodia network survey

The Pavement Management System, PMS, had been started developing since year 80’ in Taiwan area. With the systematic and efficient management, the decision of the policy and road maintenances can be efficiently developed and executed. Besides, new inspection instrument and equipment have been used for collecting and analysis enormous information of the road network. Recently, the Government had reduced the budget of the public works, it is more important to excise the limited resources to increase the efficiency of the road maintenance policies.
Highway Development and Management Tool -- HDM-4, that was developed by the World Bank, combines technical and economic appraisals of road projects. It can not only offer the extensive models to apply many different functions of the life-cycle of the road, such as the planning, programming, preparation, operations and fee of the road improvement, the road user cost and effect of the society environment, but also provide the functions for the parameters adjustment of the local environment, which makes the models can be easily applied to many different countries. This tool can provide three applications for Strategy analysis, Program analysis and project analysis for user.
This research employed the HDM-4 to collect and analysis the properties of the vehicles and the relation of the cost in the Taiwan area to establish HMD-4 models of the relevance vehicle data in the Taiwan area. Moreover, according to the current situation and operation instruction of the road maintenance in Taiwan, choice the best work methods and standards which can be applied for Taiwan to support the maintenance engineering. After all, I selected the Tao-Yuan area road network to proceed the program analysis and strategy analysis practically. And for example have the road management in Taiwan, to evaluate the problems for the combination HDM-4 and domestic road management system and provide the future application and developing direction for the HDM-4 in Taiwan.

In Chinese.

Bridge, culvert and ford investment programme for Samoa

Seawall investment program for Samoa

Road investment programme for Samoa

Identifying maintenance treatments with HDM.

The Highway Design and Maintenance Standards Model (HDM-III), developed by the World Bank, has been used extensively for the economic evaluation of road projects over a period of approximately 15 years. The Highway Development and Management Tools (HDM-4) was released early this year (2000) as the result of a process of upgrading and extension of the HDM-III. Both these models were applied to a case study, the Nsoko-Maloma road in Swaziland, in order to gain insight on the changes and improvements achieved in HDM-4. The paper provides an overview of the development of the  HDM-III and HDM-III Manager (which was used for the analysis), and the improvements implemented in HDM-4. A description of the case study and data required for the economic evaluation process are then addressed. The output of the two models is compared. It is shown that with regard to the sub-models the most important effect is the lowering of vehicle operating costs and the increase in travel speed which result from the adjustment of the sub-models for the improvement in the efficiency of motorised vehicles. The HDM-4 consequently produced lower values for the benefit-cost ratio and internal rate of return on the case study. When compared to the justification level, however, this reduction did not influence the economic viability of the project. In conclusion the improvements of HDM-4 as observed in the analysis are summarised. These are a modern-day programming style and wider options with regard to the definition of the vehicle fleet, upgrading choices, pavement types, seal types and other maintenance actions.

Report describing how the HDM PDWE model was implemented in New Zealand for pavement management.

Paper on applying HDM-4

Optmizing pavement investments with HDM.

Network level analysis using HDM-4 for road network in Estonia.

Report describing how the HDM PDWE model was implemented in New Zealand for pavement management.

Application of HDM-4 in Australia to determine the treatments which give the lowest life-cycle costs. Good example of a strategic analysis with some innovations.

Application of HDM-4 in Australia to determine the treatments which give the lowest life-cycle costs. Good example of a strategic analysis with some innovations.

Tonga road maintenance project. The project calibrated HDM-4 to Tonga and used it to investigate maintenance funding requirements.

Tonga road maintenance project. The project calibrated HDM-4 to Tonga and used it to investigate maintenance funding requirements.

Tonga road maintenance project. The project calibrated HDM-4 to Tonga and used it to investigate maintenance funding requirements.

Study with HDM-III on the relationship between optimal design standard and a country's level of economic development

World Bank paper on using HDM to justify paving unpaved roads

Paper describing the techno-economic approach to prioritizing road investments in Gujarat

Dissertation on the adaptation and application of HDM-III to Iceland. Published with permission of author.

Application of HDM-III to determine road investment program for Nepal

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

Papers presented during workshop on application of HDM-III. Used as part of the HDM-4 development process.

Paper showing how HDM can be used to establish design standards for new pavements

TRB Conference. Paper showing how HDM can be used to establish design standards for new pavements

Paper describing how to undertake an economic analysis with congested traffic. Approach was adapted and enhanced for HDM-4

Paper describing how to undertake an analysis of rehabilitating a paved road.

Paper describing how to undertake an analysis of upgrading an gravel road.

Paper describing how to undertake an economic analysis with congested traffic.

Short note on modified version of HDM-III for Thailand

Calibration and application of HDM-III for a feasibility study in Nepal.

Calibration and application of HDM-III for a feasibility study in Nepal.

Calibration and application of HDM-III for a feasibility study in Nepal.

How HDM-III was modified and calibrated to Myanmar for the Comprehensive Transport Study.

How HDM-III was modified and calibrated to Myanmar for the Comprehensive Transport Study.

This report was released the by the World Bank shortly after HDM-III. It is an important policy document which gives an overview of the state of road networks, the options for maintaining roads, and the consequences of not maintaining them, before moving on to the institutional challenges and financial requirements. It was essentially a \'wake up\' call for road owners on the need to do something to prevent their infrastructure from being a constraint on economic development and growth.