Positive results as placing booms and a full pump fleet help Honolulu Airport’s new car rental facility take shape.
While we are understandably preoccupied with the complexities of our “new normal,” in the construction world, life is going on, work is still getting done, and projects under way — for years in some cases — continue moving toward completion. Case in point: major renovations and expansions to Honolulu’s Daniel K. Inouye International Airport (HNL), which were first announced in 2013. One of the higher-profile components to that $1.6 billion project is the Consolidated Rental Car Center (CONRAC) which will, when complete, totally reshape the car rental experience at HNL. At 1.8 million sq. ft. (excluding the two exterior helical ramps), the $329 million facility will be well-equipped to deal with the car renting public. Heading up the concrete pumping facet of the project is Oahu-based American Standard Concrete Pumping, which used a full contingent of pumping apparatus from trailer pumps, through a fleet of truck-mounted booms, to a pair of mast-mounted placing booms. Paradise Lost? More like Paradise Rented.
Work in Progress
Though this year will be a brutal anomaly, Hawaii’s pre-COVID tourism trade was humming along nicely, topping 10 million visitors in 2019, six million of whom made Oahu their target destination. With that influx, the demand for rental cars had grown steadily over the years and the previous approach of separate rental companies in separate locations was deemed both outdated and inefficient.
According to Greg Perrin, president of American Standard Concrete Pumping (ASCP), the project is being done in three phases: Phase 1, which involved moving the existing rental companies to a new interim location before construction of a new five-story rental return facility; Phase 2, which called for construction of a separate five-story rental car pick-up facility as well as an underground pedestrian tunnel; and Phase 3 which entails moving the rental operations from the old structure into the new one and simultaneous completion of construction. The rental return facility will include rental car offices, rental car parking (approximately 4,400 parking stalls compared to the current 895), 16-car wash bays, and 64 fueling positions. Concrete work began in earnest in January 2017.
“Part of the reason this project is slated to take longer than most is because it’s broken down into those separate phases, some of which overlap,” said Alex Miller, quality control manager for Contrack Watts, the general contractor. “Trying to keep the rental car facility fully operational and keep customers satisfied — while work was ongoing — was a full time effort. In addition, construction of the airport station for the Honolulu Area Rapid Transit, as well as the rail project itself, is happening adjacent to our work. That’s resulted in congestion that has impacted both workspace and delivery schedules.”
On the Rise
All those challenges aside, ASCP began subgrade work with the pouring of 1,200 18” diam. auger cast piles in advance of the 6-inch thick foundation slab for the rental car-return facility. To deal with the island’s high water table, 140 36-inch diam. secant piles were also pumped. Each of the foundation slabs for the rental car pick-up and return facilities contained about 5,044 cu. yds. of concrete, almost all of which was pumped. Truck-mounted boom-pump sizes ranged from a Schwing BPL 500(1418) with 250’ of slickline and hose to 65-meter.
“These are sizeable structures,” said Perrin. “The footprint of each large facility is roughly 392’ by 948’. We pumped 285 columns per floor, ranging in size from as small as 12” X 12” up to 32” X 32”, and pumped the 8” and 10” thick walls as well. The post-tensioned, reinforced decks for each five-story structure averaged 6” in thickness.”
Because of the impressive nature of the project — more than 82,000 cubic yards of concrete went into each structure — getting all that mud down was handled by an equally impressive armada of concrete delivery solutions. ASCP’s options ranged from a pair of Schwing SP-500 trailer pumps to the aforementioned fleet of truck-mounted boom pumps. In spite of all that iron (and more), however, to get the bulk of the above-grade pumping effort done, Perrin and his team turned to a pair of separate placing booms (SPBs).
Pumping concrete in the large footprint of each CONRAC structure — more than 8.5 acres — is not for the feint of heart. To ensure they got the necessary reach as each structure rose, ASCP called upon a pair of Schwing S 39 SXD 39-meter separate placing booms with 2023-5 pump kits, mounted on 40’ octagonal self-climbing masts. Each boom was powered by a Gen-2 power pack, which lightened the separate placing boom’s weight by splitting the power pack and boom. Doing so allows easier lifting by a tower crane, when needed, during movement.
“At the outset of their implementation, the pair of SPBs were free-standing,” said Perrin. “Using either the cross-frame foundation mounts with anchor bolts or — when utilities prohibited an in-ground foundation from being used —a ballasted cross-frame to mount above ground. Because of the massive size of each structure, we needed a total of 13 different locations to get the necessary coverage. Even then, some areas could not be reached, so we used the 65-meter pump until the SPB could come back into play.”
He added that, although individual jumps with the self-riser were quick, a complete remove and relocate process took a crew roughly two-days to accomplish. Such an R&R included removing the boom, powerpack, mast sections, and cross frame, roughly 200-feet of 5-inch HD bolt-on pipeline, diverter, and pump; relocating the entire package; torqueing the components down; re-installing the pipeline and hold downs; reconnecting power and testing.
“The versatility of the mast system has been key and is, in fact, currently coming into play,” said Perrin. “The general contractor discovered utilities right where a ground mount was needed, so we just utilized the ballasted frame free standing octagonal mast, and cross-frame system with counterweights. Having options like that available is a huge benefit to us. The mast system is well-designed, and by far the fastest I’ve ever used for a free standing application.”
Making a Connection
In addition to the car rental and return structures, a small, 2,500 sq. ft. access tunnel, was built and tied into an existing structure that was previously used by the rental car companies before their relocation. Because the airport is at sea level, a secant wall was built and nearly 11 million gallons of water were pumped out and processed on-site before actual construction could begin. With that done, ASCP used an SP 500 to provide shotcrete for bank retention, then utilized pumps ranging in size from 24-meter to 65-meter for the various wall and deck pours. However, Perrin is quick to add that the separate placing booms were the real work horses on the job.
In light of the project’s overall complexity, it should come as no surprise that 43 different mix designs were needed throughout the project. According to Miller, the concrete performance demands were as varied as the organizations requesting them.
“A number of different admixtures, including MasterGlenium 7920, & 3030, V-MAR 3, MCI-2005 NS, were tested and utilized for work below the water table,” he said. “We also had different requirements from multiple agencies — HIDOT, Hawaiian Electric, DOR, etc. — with specific requirements. In addition, we changed our aggregate sizes for better consolidation and made tweaks for high early mixes, in order to be able to stress 24 hours after placement.”
No Task Too Big…
The challenges the average concrete pumping company faces are obviously magnified when that operation is more than 2,000 miles from the closest mainland support. With that in mind, Perrin cites what he sees as being key to their success.
“I began my career in California, so I’ve seen both worlds,” he said. “Being based in Hawaii, one of the most remote landmasses on earth, is a huge challenge; we can’t simply pull resources from another location to meet our needs for tomorrow’s schedule. So it’s critical that we have the people, including well-trained operators, mechanics, and office staff, as well as the equipment, always available to react to the cycles and fluctuations in the Hawaii construction market. But, I am very fortunate to work on one of the most beautiful places on earth, anchored by a group of extremely talented people, and backing our efforts with the best concrete placement equipment money can buy.
“There is a phrase that encompasses the traditional Spirit of Aloha which really sums up our situation here nicely. It is: A’ ohe hana nui ke alu ‘ia , which, translated, means: ‘No task is too big when done together by all.’ So yes, it can be a challenge, but living with ‘Aloha’ makes it all worth it.”
The Daniel K. Inouye Airport CONRAC is slated for a fall, 2021 opening.
Owner: Hawaii Department of Transportation, Airports Division
Design Architect: Demattei Wong Architecture, Dallas, Tex.
General Contractor: Contrack Watts, Inc. Honolulu, Hi.
Pumping Contractor: American Standard Concrete Pumping, Waipahu, Hi.
Concrete Supplier: Hawaiian Cement, Aiea, Hi.
Equipment: Two Schwing S 39 SXD concrete pumps with detachable booms, Schwing 26M, 34M, 47M, 52M, 55M, 58M, and 65M truck-mounted concrete pumps with placing boom; Schwing SP-500 trailer pump, Schwing BPL 500(1418) city pump.