Highway engineering

These are the pages of the Highway Engineering Research Group (HERG). My name is Dr David Woodward and I look after this group that forms part of the Centre for Sustainable Technologies.

Highway engineering research at the University of Ulster was established in 1985 under the leadership of Prof. Alan Woodside. 

All of the research carried out since has had a similar aim i.e. to promote new and innovative research into road construction leading to improved understanding and prediction of highway material performance.

We have developed strong links with other academic institutions, government agencies and industry both nationally and internationally. The focus for research concentrates on a number of key areas that HERG have identified as being crucial to the future of highway engineering. These are:

• Fundamental understanding on asphalt mixes.
• The prediction of long term performance.
• Sustainable technologies.

This may be summarised as the development of better performing, more durable sustainable materials optimised for in-service.

The development of HERG in these key areas has only been possible by close collaboration with the highway industry leading to product enhancement and / or development and the award of post-graduate degrees.

We believe that our research should be disseminated widely through publication in journals, at leading conferences, professional institution meetings and by short courses and seminars.

HERG has now one of the leading university highway research laboratories in UK. We can assess materials using a wide range of standard and non-standard methods developed in-house to understand material response to simulated environmental and in-service stressing conditions. 

The laboratory has specialised equipment such as the Road Test Machine and ULTRA which subject asphalt materials to full-scale wear conditions and determine high speed skid resistance of materials respectively.

Staff from a range of backgrounds share their experience to meet the needs of a rapidly changing modern highway environment and aim to provide a safer, more economical and durable highway construction.

So, please look at our pages, find out what we do and if you see something that gets your interest please do not hesitate to contact me.

Facilities at HERG:

HERG offers the following facilities to assess highway engineering materials.If you do not see what you want contact David Woodward for further details of facilities provided by HERG.

Aggregate assessment

HERG has considerable experience in the assessment of aggregate properties and prediction of likely in-service performance. The HERG laboratory offers a wide range of techniques to both standard and non-standard in-house test methods. The following is a selection of the main test methods available:

European Norm test methods -Sieve analysis, Los Angeles, micro-deval, Polish Stone Value, Aggregate Abrasion Value, Magnesium Sulfate Soundness.

Testing to BS 812  although replaced by Euro Norm test methods, the following BS 812 test methods can be carried out: Flakiness index, Elongation index, Relative density and water absorption, Aggregate impact value - wet and dry, Aggregate crushing value, Ten percent fines value - wet and dry, Aggregate abrasion value, Polished stone value, Magnesium sulphate soundness value.

Testing of non-standard aggregate sizes - aggregates are frequently used in sizes which are not assessed in standard testing. HERG have developed modified test methods to assess such aggregate. Methods include the following:Aggregate abrasion value - 3mm size, Polished stone value - 3mm size, micro-deval test - 0-5mm size.

Other aggregate test methods - Methylene blue test (UUJ method), Ball mill test for assessing paver sand, Polished Paver Value to determine skid resistance of block pavers, Thermal shock properties of aggregate

Assessment of hot and cold bituminous mixes

Asphalt test specimen preparation Marshall compaction,ELE Servopac Gyratory compactor, Cooper Roller compactor, vibratory hammer compaction.

Permanent deformation - dry tracking at 45 or 60C, wet tracking using the immersion wheel-tracking apparatus.

Nottingham Asphalt Tester - The Nottingham Asphalt Tester (NAT) is used for quality control, mix design, end product specification, failure investigation, pavement evaluation, assessment of new materials and durability checks. The following tests may be carried out - elastic stiffness, resistance to fatigue cracking, resistance to permanent deformation using the uniaxial creep test, resistance to permanent deformation with the repeated load axial test 

On-site assessment - texture depth using the sand-patch test, slip-resistance / skid-resistance value using British Pendulum tester or micro-GripTester, Relative Hydraulic Conductivity, longitudinal profile using the Rolling Straight Edge, skid resistance using GripTester or micro-GripTester.

Quarry assessment - visual assessment of in-situ rock quality, specialised sampling to determine vertical and lateral variation in quality, aggregate quality / quantity estimation.

Specialized facilities - asphalt surface texture using 3d photogrammetry or 3d laser techniques, high speed wear using the ULTRA, BBA HAPAS approved wear testing of High Friction Surfacings, Accelerated wear testing of asphalt using the Road Test Machine, aggregate / asphalt colour, XSensor high resolution and lower resolution pressure pads.