IQALUIT AIRPORT REDEVELOPMENT PROJECT Pavement Design & Construction Challenges Bryan PALSAT, P. Eng. & Jean-Martin CROTEAU, P. Eng. SUMMARY

» Context » Scope of the project » Logistics » Construction activities » Technical challenges CONTEXT – ,

» Nunavut • Created as a new territory April 1st, 1999 • 2,093,190 km² • 32,000 inhabitants » Iqaluit • Formerly • Iqaluit means « the fish » in • First permanent settlement in 1942 • Nunavut’s capital since Dec. 1995 • Became a City on April 19, 2001 • 8,000 residents

SCOPE OF THE PROJECT

» Public-Private Partnership type project • Signed on September 10th, 2013 » Client • Nunavut Government • Client’s representatives: Partnerships British Columbia » DBFO contract • Construction: 4 years (2014-2017) • Operational commitment: 34 years (2014-2047) » Capital investment • Approximately $300M

8 SCOPE OF THE PROJECT

Client’s representative

Design & Build Operation

9 SCOPE OF THE PROJECT

» Buildings • A new 100,000 square feet Air Terminal Building • Combined Services Building to house all airport and safety vehicles » Civil work • Reconstruction of existing Taxiway A • Construction of two new Taxiways (G and F) • Widening of Apron I • Rehabilitation and repaving of 16-34 • Expanding parking lots and local access roads

10 SCOPE OF THE PROJECT

Rehabilitation existing surface 310 000 m² with 40 000 m2 of structural repairs

Various extensions 90 000 m²

New terminal 9 500 m² + new service building 4 500 m²

Roads and parking 30 000 m² SCOPE OF THE PROJECT - Video

12 LOGISTICS – Background information

» Key dates • 1943: Creation by USA • 1949: Sold to • 1953: 17-35 Runway • 1957: Paving • 1976: Overlay by Sintra • 1992: Paving and repairs

13 LOGISTICS – Bitumen and tack-coat binder

» Two grades • PG 52-40 – New Construction • 2016 → 1050 tonnes • 2017 → 480 tonnes • PG 52-34 – Rehabilitation • 2016 → 570 tonnes • 2017 → 1550 tonnes » Tack-coat binder » Challenges • Melting operation Question for the audience: What would you have done • Management all empty drums knowing the logistical • 9000 empty drums/year challenges? • 20 containers/year to ship back 2011 CONSTRUCTION ACTIVITIES – 2014-2015 2015 CONSTRUCTION ACTIVITIES - 2016 2016 CONSTRUCTION ACTIVITIES - 2017 2017 TECHNICAL CHALLENGES

» Repairs related to permafrost » Excavation in permafrost » Asphalt mix-designs » Friction measurement » Ride Condition Index (RCI) » Structural Condition Rating (SCR) » Pavement strength verification » Crack sealing » Tack-coat and prime coat TECHNICAL CHALLENGES – Repairs TECHNICAL CHALLENGES – Repairs

»Geophysical investigation (Laval University) TECHNICAL CHALLENGES – Repairs

»Identification of potential ice wedges TECHNICAL CHALLENGES – Repairs

»Identification of potential ice wedges TECHNICAL CHALLENGES – Repairs

»Correlation with surface condition assessment TECHNICAL CHALLENGES – Repairs TECHNICAL CHALLENGES – Repairs TECHNICAL CHALLENGES – Repairs TECHNICAL CHALLENGES – Asphalt mixes

» Binders • PG 52-40 for new construction, and • PG 52-34 for overlays » Aggregates • One source of aggregate (local quarry) • No sand available or washing facility » Traditional Marshall mixes for airports • Challenges • Volumetrics i.e. voids & VMA • Stability • Three mixes needed to be developed TECHNICAL CHALLENGES – Asphalt mixes

» Mixture #LC02005 • New construction, apron extension, taxiways & pavement repairs » Mix-design • 15% of RAP 0-10 mm • 30% of 10-14 mm • 55% of 0-5 mm • 5.1% of bitumen PG 52-40 » Additional testing • TSR: 93,4% > 75% • Rutting 24.2 mm @ 10 000 cycles TECHNICAL CHALLENGES – Asphalt mixes

» 2015 paving work

Pavement repairs

Apron extension & taxiways

Runway first overlay TECHNICAL CHALLENGES – Asphalt mixes

» 2016 paving work

Pavement repairs

Apron extension

Runway first overlay TECHNICAL CHALLENGES – Asphalt mixes

» 2017 paving work

Pavement repairs

In front of the ATB

Runway final overlay APRON EXTENSION TECHNICAL CHALLENGES – Asphalt mixes

» Mixture #SC01500 →Volumetrics issue • Existing pavements →Stability issue →Concerns over communicated voids » Mix-design →Concerns with resistance to deformation • 15% of RAP 0-10 mm • 43% of 5-10 mm • 42% of 0-5 mm • 5,1% of bitumen PG 52-34 » Additional testing • TSR: 93,4% > 75% • Rutting 12,7 mm @ 10 000 cycles • Permeability results = Same as a fine TECHNICAL CHALLENGES – Asphalt mixes

» Additional testing TECHNICAL CHALLENGES – Asphalt mixes

» 2016/2017 paving work

Apron overlay 2016

Apron & taxiways overlay 2017

TECHNICAL CHALLENGES – Asphalt mixes

» Mixture #LC02550 →Concerns over communicated voids • Landside i,e, streets and parking lots →Concerns with resistance to deformation » Mix-design • 15% of RAP 0-10 mm • 10% of 10-14 mm • 39% of 5-10 mm • 36% of 0-5 mm • 4.75% of bitumen PG 52-40 » Additional testing • Rutting deformation: • 6,3 mm @ 10 000 cycles • 8,7 mm @ 30 000 cycles • Permeability results = Same as a fine TECHNICAL CHALLENGES – Asphalt mixes

» 2016/2017 paving work

2017

2016

TECHNICAL CHALLENGES - Riding Condition Index (RCI)

» Pre-overlay / repair runway condition: TECHNICAL CHALLENGES - Riding Condition Index (RCI)

» Challenges in profiling the runway • Access limited to 10 to 15 min windows (not suitable for SurPRO) • If possible full runway coverage » The solution • Shipped an ICC 2-laser profiler and instrumented a local pick-up truck » Collected profile and RCI • Pre-construction • Post – profile mill and overlay • Post – final overlay (profile used for acceptance) TECHNICAL CHALLENGES - Riding Condition Index (RCI)

»Ride Comfort Index (RCI) vs. International Roughness Index (IRI) • Direct correlation where • RCI 7.2 ~ IRI 1.3 m/km • RCI 5.0 ~ IRI 2.7 m/km • RCI 6.0 ~ IRI 2.0 m/km • Target • RCI ≥ 7,2 i.e. less than IRI 1.3 m/km TECHNICAL CHALLENGES - Riding Condition Index (RCI)

» RCI – Pre-construction TECHNICAL CHALLENGES - Riding Condition Index (RCI)

» RCI - Post profile milling and overlay TECHNICAL CHALLENGES - Riding Condition Index (RCI)

» RCI - Post final overlay TECHNICAL CHALLENGES – Pavement strength

» Pavement design to provide Pavement Load Rating (PLR) of 12 » Granular thickness not compliant with design in de-icing area • Design total thickness – 1030 mm • As-build thickness – 960 mm » Measurement of deflection was proposed to verify pavement strength • Benkelman beam measurement program was developed • Reasoning… • Well suited for small areas • Simple logistic (as opposed to other devices) • Well documented method TECHNICAL CHALLENGES – Pavement strength

/ ∗10 TECHNICAL CHALLENGES – Pavement strength

Subgrade bearing Equivalent granular Subgrade bearing strength criteria using Station thickness strength a PLR 12 t (mm) S (kN) S (kN)

2+140 910 188 ≥ 140

2+160 975 194 ≥ 131

2+185 958 192 ≥ 130 TECHNICAL CHALLENGES – Reflective cracking

» A binder course was placed in 2015 on the north part of the runway » In January 2016, reflective cracks appeared on the new pavement • Anticipated by the design-builder by not the client but not by the client • Sealing of the crack was requested » An emulsion-based crack sealant was selected to ensure it would not adversely affect the final overlay » The binder course place on the south part of the runway was also crack sealed in 2017 prior to the final overlay • To not compromise the SCR (Structural Condition Rating) TECHNICAL CHALLENGES – Reflective cracking TECHNICAL CHALLENGES – Prime & tack-coats

» Prime coat • Removed from specification » Tack coat • Logistic challenge →“Yr-1” • Needed to be stable at < 0°C • …emulsion out • Specification → cutback • Risk assessment unfavourable • …cutback out • Challenges • Stable • “Sprayable” No solvent and no water • Wetting capability • Adequate tacking A specific tack-coat product was develop for this job • Good bonding Jean-Martin Croteau, P.Eng. Bryan Palsat, P.Eng. Technical Director Pavement and Materials Engineer Colas Canada Inc. Tetra Tech Canada Suite 2400, 4950 Yonge Street 14940, 123 Ave NW Toronto, ON M2N 6K1 Edmonton, AB T5V 1G9

Tel: +1 416 293-5443 Tel.: +1 780 451-2121 Mob.: +1 780 868-2527 Mob.: +1 604 220-8794 [email protected] [email protected] www.colascanada.ca www.tetratech.com RAPPORTS DE NON-CONFORMITÉ 2014-2015-2016 » Gécan est en charge de relever les NCRs et de les régler. » Depuis le début des travaux 2014, combien de NCRs? • 2014: 13 • 2015: 6 • 2016: 22 • 2017: 0 ? » Est-ce qu’on peut éviter ces NCRs? • Définitivement » Comment? • Contrôle vigoureux du chantier • Excellente communication • Connaissance des plans et devis • Travail d’équipe • Rapport qualité complet