partnership.tenacity.enjoyment.care New Zealand Airfield Pavement Surface Types – Evaluation, Design, Maintenance and Rehabilitation John Marsh General Manager Airports, Beca Infrastructure Ltd 2010 FAA Worldwide Airport Technology Transfer Conference April 20 th 2010

partnership.tenacity.enjoyment.care Beca Group  Multi disciplinary engineering and management consultancy  Founded in 1917  2,500 employees  Main groups in New Zealand, Australia and Asia  Proud history of successful airport projects since the 1970’s  Over 70 focused and dedicated airport experts  Current major projects in Auckland, Christchurch, Melbourne, Brisbane, Adelaide, Perth, American Samoa, Marshall Islands and various Defence airfields

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care New Zealand

partnership.tenacity.enjoyment.care Facts and Figures  Population 4 million  7 international airports, plus many smaller regional ports  Auckland –13 million PAX –156,000 movements  Christchurch –6 million PAX –136,000 movements  Wellington –5.5 million PAX –112,000 movements  Variety of aircraft from A380 and B777 to small turboprops and GA

partnership.tenacity.enjoyment.care Pavement Surfacing Types

partnership.tenacity.enjoyment.care Pavement Maintenance Issues  Predominantly flexible asphalt pavements other than concrete at Auckland Airport  Usual range of issues with weathering, ageing, fatigue cracking, bleeding and stripping, groove closure, rutting, fuel damage, concrete spalling and fatigue  Challenges of weather extremes from sub- tropical in the north to cooler temperate and alpine conditions in the south  Range of airfield pavement management systems adopted, from simple inspections to more rigorous pavement management systems

partnership.tenacity.enjoyment.care Innovation and Sustainability  Lower population and associated economic challenges has led to a culture of innovation and sustainability  Material recycling –Crushed concrete –(RAP) Recycled asphalt pavement –Other fillers considered  Lower grade aggregates –Stabilisation with cement, lime and bitumen –Used in low importance pavements or base layers  Innovative solutions to construction e.g. slab removal  Low energy asphalt mixes

partnership.tenacity.enjoyment.care Auckland Airport: Concrete Technology  Auckland Airport has over 13 million passengers per year  Concrete pavements originally constructed in the 1960’s  Single Runway 05/23 3,635m (11,925’) long  By the early 1990’s pavements exhibiting fatigue cracks and spalling  Areas of slab replacement completed under displaced threshold  Critical central portion needed a new solution

partnership.tenacity.enjoyment.care Auckland Airport Main Runway 23L-05R

partnership.tenacity.enjoyment.care Epoxy Underslab Injection  Methodology developed to form a stiff beam along each free edge of the cracked slab to delay the time until further deterioration  Challenges with open graded scoria subbasecourse  Laboratory trials, dynamic trials and full scale test strips  Deflections reduced by approximately 15%  Over 1,000 slabs have now been injected  >90% success rate  10 year extension until eventual slab replacement required

partnership.tenacity.enjoyment.care Epoxy Underslab Injection

partnership.tenacity.enjoyment.care Epoxy Underslab Injection

partnership.tenacity.enjoyment.care Expedient Slab Removal  Modified mining loaders  Customised forks  Cutting and lifting slabs  Less noise and debris  600% productivity gains

partnership.tenacity.enjoyment.care Expedient Slab Removal

partnership.tenacity.enjoyment.care Concrete Thermal Monitoring  Research project to determine cumulative temperature hours to develop required flexural strengths  Laboratory testing programme  Concluded insitu 2000 ºC-hours would be sufficient to develop >4.8MPa (700psi)  Monitoring during construction demonstrated required strength achieved in 48 hours  Early opening of the runway reduced disruption to operations

partnership.tenacity.enjoyment.care Concrete Thermal Monitoring

partnership.tenacity.enjoyment.care Christchurch Airport: Asphalt Technology  Christchurch International Airport has over 6 Million passengers per year  Primarily thin asphalt pavement surfacings over unbound gravel base layers and a natural gravel subgrade  Main runway with a cross wind runway  Annual programme of airfield maintenance  Collaborative approach to maintenance established with an airfield works framework with owner, designer and contractor  Goal is to safely and cost effectively implement the annual pavement maintenance works whilst implementing a number of airfield paving innovations and minimising disruption to airfield operations

partnership.tenacity.enjoyment.care Environmental Considerations  Environmental objectives set for the project  Meeting CIAL’s environmental goals (the Southern Hemisphere’s first CarboNZero airport)  Use of recycled materials and low energy asphalt on airfield pavements  Minimal impact on airport neighbors  Establishment of Environment Management Plans

partnership.tenacity.enjoyment.care Sustainable Asphalts  Recycled asphalt pavements  15% to 30% RAP on shoulders and taxiways  Coolpave ™ warm mix AC trialed over the last 3 years  Combination of both  50% to 90% RAP in the future?

partnership.tenacity.enjoyment.care RAP Asphalt Mix Properties  RAP mixes found to be less consistent than traditional mixes  Lower workability and tendency to cool more rapidly  Higher temperatures and softer bitumens have been trialed.  Further evaluation of durability Mix (Lab Trials)Stability (kN)Resilient Modulus (MPa) Wheel Tracking (mm) AC , AC14 with 15% RAP 185, AC14 with 30% RAP 175,100<1.0

partnership.tenacity.enjoyment.care Warm Mix AC Properties  Coolpave ™ technology by contractor Fulton Hogan using LEA Co. System  Placement temperatures under 100 º C (212 º F)  40% reduced energy, lower emissions and safer  Encouraging results, although lower stiffnesses to date and more compactive effort required Mix (Field Results)Modulus at 4 weeks (MPa) Modulus at 1 year (MPa) AC142,4002,900 AC14 with Coolpave2,0002,500 AC14 with 15% RAP3,5004,200

partnership.tenacity.enjoyment.care Christchurch Airport AC Paving