The reconstruction of Runway 8R-26L at Honolulu International Airport, known as the Reef Runway, stands as one of the most technically demanding asphalt paving projects ever executed in the Pacific region. Built entirely offshore on a coral fill reef, opened in 1977, and never fully resurfaced in 36 years, the 12,000-foot by 200-foot runway posed challenges that conventional milling and paving methods could not meet. Jas. W. Glover, Ltd., a locally owned Hawaiian contractor operating since 1935 with approximately 200 employees and its own aggregate quarries, took on the project with a strategic deployment of Trimble 3D milling and 3D paving control technology. The stakes were extraordinarily high, with the FAA and Hawaii Department of Transportation imposing a 15-day deadline per phase and $240,000 per day in liquidated damages for any overrun. For context on how large-scale airfield paving projects are managed, see the Stewart International Airport Runway Rehabilitation Airfield Asphalt Paving project. This article examines the methods, outcomes, and practical lessons from the Reef Runway reconstruction.
Project Background and Technical Challenges
The Reef Runway: An Offshore Engineering Landmark
Constructed in the mid-1970s on a coral fill foundation extending into Mamala Bay, the Reef Runway served commercial aviation at Honolulu International Airport and military operations at Hickam Air Force Base. It also served as an alternate landing site for the NASA Space Shuttle program. Since opening, it had received only patch maintenance and never a complete mill-and-overlay reconstruction. Decades of service left the pavement with variable cross-slopes and elevation inconsistencies that made conventional stringline-based methods impractical. Glover brought extensive experience from projects including the H-1 Freeway, Pali Highway, and Hilo International Airport runways, but recognized this project demanded new technology.
Why Traditional Methods Would Not Work
Four factors made conventional stringline-based methods unsuitable for the Reef Runway:
- Variable cross-slopes across the 200-foot width required hundreds of survey points needing continuous recalculation as work progressed
- Variable depth milling was specified at 4 inches at the outer edges and 6 to 8 inches in the center portion
- Extreme length of 12,000 feet demanded a large survey crew working constantly for grade control
- 24-hour shift operations made stringline methods impractical at night when visibility was reduced and stakes could be displaced
Gregg Nathaniel, Glover’s construction superintendent, noted that the existing variable slopes made it nearly impossible to mill everything to the new profile without 3D technology. The penalty structure left no margin for error, making precision essential for project viability.
Deploying Trimble 3D Technology for Precision Control
Equipment Strategy and Crew Training
Glover made a deliberate decision to acquire and learn the Trimble 3D technology before the Reef Runway project began. The initial investment included a Trimble PCS900 3D mill and 3D paving system installed on a Roadtec RX-900 milling machine and a Caterpillar AP1055D asphalt paver. The company also purchased four Trimble SPS930 Universal Total Stations and two rover units. Rather than deploying directly on the high-stakes project, the team trained at Hilo International Airport during summer 2013, building proficiency on test sections.
For the Reef Runway, Glover scaled up with a second PCS900 system on an additional RX-900 mill and AP1055D paver, four more total stations, and two additional rovers. This allowed two 12.5-foot-wide 3D mills and two 25-foot-wide 3D pavers to operate simultaneously, maximizing production within the tight 15-day phase windows.
How the 3D Control System Worked
The PCS900 system operated through a structured workflow integrating digital design models, machine-mounted sensors, and robotic total stations:
- The project design was built as a 3D surface model in Trimble Business Center software, defining exact elevation, slope, and alignment parameters
- The model was transferred to onboard computers in each machine cab for real-time operator reference
- A robotic SPS930 total station tracked a prism on each machine, continuously measuring its 3D position
- The system automatically adjusted milling drum depth or paver screed height to match the digital design
- Additional total stations were prepositioned for leapfrog transfer every 1,000 feet, so machines never stopped moving
The operator display showed color-coded areas on grade, above grade, or below grade. No stringlines, manual stakes, or constant surveyor intervention were needed. The system guided the milling drum to cut the ideal depth and slope, removing only the minimum required material.
Phased Construction Sequencing
Glover divided the reconstruction into three phases to maintain airport operations:
| Phase | Section | Length | Duration | Operational Status |
|---|---|---|---|---|
| Phase 1 | East end | 3,000 ft | 15 days | West 9,000 ft active |
| Phase 2 | West end | 3,000 ft | 15 days | East 9,000 ft active |
| Phase 3 | Center section | 6,000 ft | 15 days | 24-hour total shutdown |
The team worked in 24-hour shifts through all phases. A four-person survey crew managed the entire project using Trimble total stations to check grade and capture as-builts. Nathaniel estimated traditional methods would have required two to three times more surveyors. Similar phasing strategies were employed on the Fort Lauderdale Hollywood International Airport South Runway Construction project, where maintaining operational runways during construction was equally critical.
Performance Outcomes and Quality Metrics
Schedule Compliance Under Penalty Pressure
Glover completed every phase within the 15-day window. The overall paving portion finished two days early, avoiding any exposure to the $240,000-per-day liquidated damages. Phase 3, the center section at 6,000 feet, was the most demanding segment in length and square yardage. It was completed in the same timeline as the shorter phases, demonstrating the productivity advantage of 3D-controlled operations. The machines ran continuously without stopping for grade checks, moving seamlessly through the leapfrog positioning system.
Surface Smoothness and Elevation Tolerance
The contract required a half-inch grade tolerance, meaning the finished surface could deviate no more than one-quarter inch above or below design elevation at any point. The final surface met this tolerance across the entire 12,000-foot length with zero grinding or corrective work required. Every section passed on the first pass, eliminating costly rework. This level of smoothness is critical for airport pavements where surface irregularities affect aircraft tire wear and fuel efficiency.
Material Yield Accuracy
The total tonnage of asphalt used was 92,469 tons, compared to the pre-construction estimate of 92,600 tons. This variance of 131 tons, or 0.14 percent, was attributed directly to the 3D system’s ability to cut exactly to grade and place material at the required thickness on the first attempt. Nathaniel noted that on previous projects using stringline methods, material overruns were a constant risk, and the contractor bears the cost of any excess. Smarter milling also meant removing only the minimum required depth, reducing waste and lowering the quantity of new asphalt needed.
Lessons for Asphalt Paving Operations
Measurable Productivity Gains
The Reef Runway project produced documented productivity improvements relevant to any contractor evaluating 3D paving technology:
- Production rate: Glover laid down 5,000 tons of asphalt per night in a 12-hour shift, compared to 2,000 to 2,500 tons on conventional jobs
- Survey efficiency: A four-person crew managed the entire project, whereas traditional methods would have required 8 to 12 surveyors
- Elimination of prep work: No stringlines, layout stakes, or continuous survey setups were needed, saving hundreds of person-hours
- Fuel savings: Continuous machine operation without stops for grade checks reduced fuel consumption per ton placed
These gains are especially significant for large-area paving where production rates directly affect profitability. For complementary material optimization strategies, the work discussed in Eb Paving Achieves 40 RAP Content With Soybean Oil Rejuvenator Technology 2 shows how reclaimed asphalt pavement can further reduce costs and environmental impact.
Support and Training as Critical Success Factors
Nathaniel emphasized that support from the Trimble team was essential to rapid technology adoption. Trimble personnel worked alongside Glover crews for extended periods, sometimes 24 to 36 hours continuously, training operators as shifts rotated. This hands-on support ensured the technology was used to its full potential from the first production day. Total stations and control components could be reused across milling machines, pavers, graders, and dozers, providing ongoing return on investment beyond this project. Similar material optimization approaches are highlighted in Eb Paving Achieves 40 RAP Content With Soybean Oil Rejuvenator Technology, where sustainable mix design maximized reclaimed content without compromising pavement performance.
Financial Implications of Precision Control
Three specific areas generated direct cost savings from the 3D technology deployment:
- Penalty avoidance: Completing all phases on schedule and finishing two days early eliminated exposure to the $240,000-per-day liquidated damages. Even a single day over deadline would have incurred substantial penalties
- Material savings: The 0.14 percent variance between estimated and actual tonnage meant virtually zero cost overrun on 92,469 tons. A 2 percent overrun would have added 1,850 tons at the contractor’s expense
- Labor efficiency: Reduced survey crew size and elimination of manual grade-checking labor lowered payroll costs across the project
Nathaniel described the Reef Runway reconstruction as a once-in-a-generation opportunity for the company. By combining 3D milling and paving controls with rigorous phasing and a skilled crew, Glover delivered a runway surface that met every specification, avoided all penalties, and achieved material yields within 0.14 percent of the estimate. The project stands as a practical case study showing how construction technology can transform a high-risk infrastructure project into a controlled, predictable operation that delivers superior quality outcomes while protecting the contractor’s bottom line.