1. Summary & Conclusions

With this document EAPA formulates the view of the European asphalt industry on the required direction of future research on asphalt. Entries are:

• Development of sustainable, durable and environmental construction and maintenance techniques
• Enhancing competitive strength of the enterprises
• Enhancing innovative strength of the industry.

Additionally, it is of major importance that the regulatory environment is enhanced in such a way that more active participation of the industry becomes feasible.

Future R&D programmes should be designed in such a way that the construction industry, aware of developing its human capital, has a possibility to actively participate, taking into consideration its special relationship to its clients and its SME structure.

More coordination in this area is essential in Europe to make R&D activities more effective.

The EAPA research items are summarised in the following table:

2. Introduction

A general increase in traffic flow, higher axle loads and tyre pressure of trucks on European roads have steadily increased the demand for stronger and more durable road pavements. The increase in traffic flow also means that traffic interruption for maintenance becomes less desirable. Additionally the road user has become more vocal in asking for quieter and safer roads, with reduced environmental impact. Therefore there has been put more focus on research in transport related areas in the last years, including road materials.

The construction and civil engineering sector is one of the largest production sectors in the European Union. It's total turnover is approximately representing 11 % of the GDP of the EU. Civil engineering accounts for 21 % of the total turnover. Furthermore the construction sector employs nearly 12.1 million people of which 75 % is in contracting. The current European R&D expenditure in construction however is estimated to represent 0.1 % of the GDP.

At the moment significant R&D efforts take place outside Europe, like the US Strategic Highway Research Programme (SHRP), which significantly bypasses R&D expenditures in Europe.

Discussions in the Technical Committee of EAPA have clarified that it is important for the industry, as the road research user representing practitioner interests, to actively participate in the decision process for road research projects much more than is the case today. This accounts especially for projects on an European level but also to some extend for the national level. Furthermore a clear statement from the industry might put more emphasis on the need to create political awareness for R&D in the field of road construction and maintenance within the 5th European framework programme.

This development has consequently now promoted the Technical Committee of EAPA to formulate a clear research policy, including a list of areas of priority on asphalt research, emphasising the strong commitment for asphalt research of the industry. In this way the document forms a good basis in relation to discussions and coordinating negotiations with other organisations like FEHRL, WERD, RILEM, Eurobitume and PIARC and towards influencing future road research carried out in EU or other funded road research programmes.

In the global perspective EAPA's sister organisation in USA NAPA already has taken a research initiative by joining all parties inside the road sector in the USA to formulate the development and implementation of research and technology activities for the asphalt industry. The initiative is named CART (Committee for Asphalt Research and Technology).

3. Background and objective

Each year billions are spend to build new roads and maintain the hundred thousands of kilometres of existing roads in Europe. Because of the paramount importance of the road network in the economic development and social cohesion of each country, the asphalt industry is continually involved in improving the product and its performance.

Varying from country to country the industry has nationally in a more or less ambitious manner tried to influence public asphalt research and establish cooperation with public institutions on research projects of common interest.

During the 1990ies the implementation of the EU single market has given transport issues, including road pavements, a stronger European dimension. Crossborder contacts and cooperation has grown rapidly. In the wake of this development towards a more international environment increasingly more public funds for areas related to transport research have become available especially within EU.

The 5th European framework programme for research, technological development and demonstration activities (1998 to 2002) is putting increased emphasis on topics like

• Promoting competitiveness and sustainable growth
• High quality innovative products and processes
• Technologies to reduce resource utilisation
• Promoting reuse and recycling of waste
• Development of products based on life cycle assessment
• Development of sustainable, safe and intelligent transport systems
• Promoting technological excellence in Europe
• Developing human capital
• Increased participation of SME's (Small & Medium Size Enterprises) in R&D programs.

Additionally the EU Commissions views on the key elements affecting competitiveness in the construction sector, as presented in the Commissions paper "The Competitiveness of the Construction Sector", identifies a number of elements that require future R&D activity. Among these are

• Quality
• Construction process
• Regulatory environment
• Technology.

All of the above aspects apply to the European road infrastructure and thus to the European asphalt industry.

In summary the following observations can be made on the current R&D situation in Europe:

• R&D activities in Europe are highly decentralised, where coordination of activities would be beneficial for the sector. No overview of available budgets in research items is available.
• Very often active participation of the industry is regulated by research institutes, but few projects can be quoted.
• Only few producers and contractors in the asphalt industry are equipped with research facilities.
• So far the asphalt industry has not defined on an European level its research priorities.

The regulatory and competitive environment in the European road sector has left fundamental research mainly to be carried our by the dedicated Road Research Centres and universities. The dedicated Road Research Centres, united in FEHRL, have proposed a Strategic European Road Research Programme (SERRP), which identifies scientific road research projects.

Even though the industry itself in this environment dedicate only limited resources for research, the industry is very determined to become more involved in asphalt research in order to influence future European asphalt research in a direction enhancing the competitiveness and innovative strength of the asphalt industry and to continuously fulfil the needs of the clients.

To accomplish this the industry has as a first step formulated a common research policy containing a list of asphalt research areas of special importance to the industry. The initial objective of the document is in other words not to raise more funds in the industry for research but to try to incorporate priority areas of research to the asphalt industry in existing research programs. Furthermore it should add to the awareness in the industry about the necessity to be involved in innovation.

The effect of this growing awareness will be increased budgets for research in road construction and maintenance.

In general EAPA acknowledges the responsibility of the industry for supporting asphalt researchers in closing the gap between theoretical research and practical implementation. Furthermore to have a sound balance between fundamental and applied research.

Overall it is the intention that this document can be used both on a national level by single member countries and by EAPA on an European level when either actively contacting the road research community or when receiving inquiries about asphalt research topics from national and international organisations and institutions.

4. Asphalt research From an industry perspective

A survey has been carried out among the members of EAPA with subsequent discussion in the Technical Committee of EAPA resulting in a list of research areas supported by at least a majority of the EAPA members.

The asphalt research areas identified by EAPA reflects an overall wish to link theoretical research to practical use/implementation. It should be mentioned that all asphalt research naturally must be in closely agreement with the development of the ongoing work in elaborating asphalt specifications and test methods on an European level.

The different asphalt research areas are grouped under the following main headlines:

1. Construction Technologies: These are strategically important to improve the competitiveness of the industry. Construction technologies has influence on a major part of the total life cycle costs for road construction and has long term consequences considering the whole product life cycle.
2. Material Technologies: Development of material technology is important in increasing durability, environmental friendly and safety performance and functional performance.
3. Production and laying Technologies: These may be upgraded by implementing Quality Assurance (QA) resulting in higher efficiency, new design and improved working environment. Implementation of new sophisticated computer technology is to be considered in EDI, etc.
4. Regulatory environment: Optimisation is needed, among others concerning DBFO contracts (Design, Build, Finance and Operate), regarding cost, durability, reliability, sustainability, maintainability, recyclability and eventually final disposal.

The following pages gives an introductory description of the identified asphalt research areas. In reality the overall research areas are closely interrelated making a clear distinction between them impossible. Therefore some of the specified research items are mentioned in more or less the same way under more headings.

Before describing in a random order each of the identified asphalt research areas separately it in conclusion should be stated that an overall research topic covering all areas is the development of methods focused on a more rapid practical implementation of research results.

4.1. Construction technologies

Pavement design, including life cycle assessment The existing empirical approach for pavement design based on practical understanding and experience employing an inventory of typical pavements suffices under a more or less static physical environment. The need for a faster adaptation to new conditions in essence requires a different approach towards pavement design resulting in a shift from a system based on empirical test methods to a system focusing on fundamental and functional properties.

Surface characteristics

The road surface has a significant impact on the safety performance, noise level and comfort level of the road user. Research is needed to further ad to the good performance of asphalt in this respect, including the development of functional test methods.

Heavy Duty Asphalt Pavement's (HDAP's)

In response to meet the increasing demands to pavements caused by the constant growth in traffic loadings mainly originating from a greater number of heavy goods vehicles (HGVs), increased HGV axle loadings, increased stresses due to slower moving HGVs, higher tyre pressures and the widespread use of "super single" tyres, the European asphalt industry, has developed the concept "Heavy Duty Asphalt Pavement" (HDAP). In this connection it should be emphasised that today's design models for HDAPs do not cover all important performance criteria, including thermally induced cracking from the surface of the pavement. The growing demand for HDAPs, however, requires a current improvement of existing asphalt pavements and the possible introduction of new ones.

Low volume roads

The larger part of the European road network exists of low volume roads. Investments in those roads, especially on maintenance, consume a large part of the budgets of many road authorities. Development of improved costeffective sustainable construction techniques for low volume roads will be very beneficial.

Maintenance methods

Today most asphalt is used in connection with pavement maintenance operations and only a smaller part is used for the construction of new roads. Especially on heavily trafficked roads maintenance operations can cause severe congestion and hereby incur large user delay costs. Generally research in more efficient maintenance techniques will further a more efficient traffic flow on the European road network combined with enhanced traffic safety. Particularly research in enhanced maintenance techniques with special reference to asphalt types placed on heavy duty pavements is important.

Special applications

Asphalt has proven to be a very cost effective product in new application areas as e.g. railroad track courses and landfill/waterproofing constructions. New design methods have to be developed in these areas.

4.2. Material technologies

Test methods

It is essential for the asphalt industry to possess reliable test methods to control and demonstrate the properties of different asphalt mixes either by functionally based laboratory tests or field tests of surface characteristics. The first relates to deformation, road wear, loading, (thermal) cracking, fatigue, adhesion, ageing, compaction etc. The latter encompasses pavement profile, roughness, texture, friction, brightness, drainage, noise etc. Therefore it is important to develop accelerated laboratory test methods which provide rational ("fundamental") information on the functional material characteristics of asphalt. Specifically, methods for Quality Control (QC) based on fundamental properties and recycling of HDP's should be encouraged.

The development of a satisfactory test specimen preparation method for mixture design which reproduces field condition also has high priority. In addition, the development of a mix design procedure based on predictive theory of asphalt pavement performance. To assess the performance properties of cold asphalt mixes, additionally test methods for cold asphalt mixes has to be investigated. USA has recently completed the Strategic Highway Research Programme (SHRP) targeted at improving the performance and durability of American roads. In this connection it is beneficial to assess the possible usage and relevance of the US SHRP test methods and specifications (especially for binders) for European conditions. Additionally evaluation of construction and performance of bituminous mixes designed by SHRP methology.

Modified binders and additives to asphalt mixtures

The bitumen industry is providing a large number of modified binders. The assessment of the potential benefits and limitations is needed to provide a decision model for the optimal use of these binders, including recycling possibilities. Other additives which may improve the performance of the asphalt product should be incorporated in the same decision model.

Asphalt recycling

Environmental considerations is very important for the asphalt industry. Adding old asphalt to new asphalt mixtures helps to reduce disposal of reclaimed asphalt and reduce the use of virgin aggregate and bitumen. The recycling concept contributes to sustainable development by optimising the use of natural resources and constitutes a closed material life cycle. A more widespread inclusion of recycled asphalt pavements (RAP) in asphalt mixtures primarily requires support from the state authorities. To further the recycling concept and improve RAP quality EAPA therefore sees a need for additional investigation of the optimisation of the recycling process taking account of economically and technically factors.

Cold mix technology

In recent years there has been a general increase in the interest to use cold asphalt mixes for road construction and maintenance. In contradiction to hot mixed asphalt cold mixes are blended without heating. This is possible by the use of bitumen emulsion. Cold mix technology is therefore especially appealing because it offers reduced emissions and energy savings. The production of cold asphalt mixes is also advantageous in remote areas where no production plants for hot mix asphalt is available. This development calls for a general research in cold mix technology to enhance the performance of this type of asphalt.

4.3. Production and laying technologies

Process controls

Quality Control/Quality Assurance is an important part in connection to asphalt production and subsequent asphalt laying. At the moment an official certification system for asphalt type testing, however, still remains to be established. Seen in the light of the coming CEN standard "Factory Production Control" describing a set of operational procedures and practices with which producers can regulate the quality of a product, it is in all circumstances necessary for the asphalt industry to improve the knowledge and understanding of Quality Control systems in order to enhance product confidence, including the laying quality. In this context it is additionally relevant to mention the experience from asphalt plants showing that it often is difficult to establish conformity between registered process input parameters and laboratory tested output.

Process controls instruments

The technological development throughout the last 10 year has resulted in the introduction of a lot of new electronic equipment in the asphalt industry in general and in connection with the production process on the asphalt plant in particular. The utilisation of computer systems and electronic devices has made it possible to carefully monitor and control most steps in the asphalt production process. The increased data flow of control parameters in reality forms the basis for optimising the plant process both in terms of environmental and technical considerations. Moreover, the development of cleaner technology and pollution abatement techniques should be furthered throughout the asphalt industry.

Asphalt laying

In many cases the process of laying asphalt constitutes one of the most critical factors concerning the future life and properties of an asphalt pavement. Therefore special attention to paver performance and control during road construction and maintenance will be very beneficial for the future properties of a road pavement.

Improvement of constituent materials

The asphalt industry pays more and more attention to aspects of recycling. In this respect there is a need to develop more refined reclaiming techniques and prehandling techniques for RAP, including RAP quality control techniques. Especially, it is important to develop better techniques for detection of tar and other contaminants in old asphalt.

4.4. Regulatory environment

Contractual relationships

The contractual relations between the asphalt contractor and the road authority is getting more and more attention these years. A shift from a traditional contract system where the client specifies the required construction and materials in detail to modern contract forms as the functional contract and DBFO contract (Design, Build, Finance and Operate) where the contractor is granted much more responsibility and liability will stimulate contractor innovation and cost effectiveness of road pavements. To facilitate the introduction of innovative products the French system of Avis Technique or European Technical Agreements should be further developed and implemented.

Technical harmonisation

The asphalt industry has established the adoption of European standards as an item of high priority and consequently prenormative research viz. research aimed at continuously improving the European standards is required. More priority should be given to make standards more performance oriented.