McCarran International Airport in Las Vegas, Nevada, has been taking off for decades. Opened in 1948, the airport has experienced enormous growth and has undergone numerous significant expansions. In fact, McCarran is known for its continuous expansions and upgrades, tripling in size between 1981 and 2005.
“We like to stay ahead of pace,” says McCarran International Airport project manager Todd Cooklin. “There was a clear growth opportunity to expand international tourism for Las Vegas. Direct international flights lead to global visitors choosing Las Vegas as the launching pad for their U.S. visit. The challenge was our city has grown around the airport so we had to be creative in how we designed the International Gate Expansion Project, and do it efficiently to minimize interruptions for the airlines.”
In February 2016 the USD 51M International Gate Expansion project kicked off with an aggressive timeline of 14 months. The design included improvements to the airport’s USD 2.4bn Terminal 3, expanding international gates from seven to 14, and building an underground tunnel connecting McCarran’s D gates directly to the U.S. Customs and Border Protection passenger arrival facility. The tunnel is under one of the main taxi lanes and features moving walkways, escalators and elevators.
“When constructing a tunnel, it’s one thing when it is a transit tunnel for vehicles. A tunnel to transport people presents many challenging details,” says Martin-Harris Construction superintendent Dennis Maestas. “First and foremost there is zero tolerance for water in the structure.”
To ensure the high level of required water tightness, McCarran’s team selected GCP Applied Technologies to waterproof the tunnel.
Design
The GCP team worked directly with the McCarran management team, architecture firm Gensler & Associates, waterproofing consultant CDC, Inc., and general contractor Martin-Harris Construction to walk through details and drawings. GCP was involved in pre-construction meetings and presented the products, specifications and details, minimizing unforeseen challenges with the drawings and prepping the project to be managed efficiently in the field.
Maestas says, “they had a great relationship with the architectural firm, working with them on the tunnel drawings, and built their products seamlessly into the design.” In addition to meeting all aspects of the project’s design, the International Gate Expansion also required working with McCarran’s owner, the Clark County Department of Aviation, to meet its requirements. Specifically, the department had requirements on the specifications of the concrete being used to construct the tunnel. CalPortland, the concrete provider for the tunnel project, used GCP admixtures to meet the department’s delivery time limitations and low shrinkage requirements.
Admixtures are used to improve or change specific properties in concrete. CalPortland director of quality control Mark Bliss says, “as a government project, additional inspections and requirements come into play.”
Construction
GCP has been used on several McCarran expansions, including a tunnel to the D Gates that was built in 2001 and the USD 2.4bn construction of Terminal 3, which included the addition of 14 gates and an automated people-mover system that connects Terminal 3 with McCarran’s existing Terminal 1 via an underground tunnel.
For the International Gate Expansion Project GCP’s Preprufe 300R pre-applied waterproofing system was on the underslab of the entire concrete floor of the underground tunnel. The system was installed on horizontal or vertical substrates prior to the placement of concrete. These pre-applied waterproofing membranes are unique multi-layered composite waterproofing sheets made from a chemically resistant HDPE film, a highly aggressive pressure sensitive adhesive and a weather resistant protective coating that allows the membrane to fully adhere to freshly poured concrete and prevent water tracking.
To water penetration at junctions, GCP has an advanced bond technology to create a seal with the concrete to prevent any entry or migration of moisture around the structure. The self-adhesive technology allows individual sheets of the pre-applied waterproofing system to be bonded together without specialized equipment, resulting in monolithic bathtub fully adhered to the concrete foundation.
The vertical walls of the tunnel were constructed using GCP’s Bituthene 3000, a high performance, flexible, preformed waterproof membrane. After the walls were installed, GCP’s Bituthene deck system was used on the lid of the tunnel. First a prep was first squeegeed out onto the horizontal deck/tunnel lids, followed by a layer of the Bituthene 3000 sheet waterproofing membrane.
“In addition to being high performing, GCP membranes are able to be electronically tested to verify water tightness and they are well suited for the extreme variations in the Las Vegas climate,” explains CDC manager Michael Lee. “During the day it can be 102 degrees and then drop to 40 degrees at night.”
In June McCarran welcomed its first direct international flights to the International Gate Expansion. McCarran now has double the number of gates available to international air carriers, serving additional visitors from around the world. The seven reconfigured gates are able to handle wide-body jetliners typically used by international carriers, including the Boeing 787 Dreamliner. One of the gates is fitted with a dual-level bridge to handle the double-decked Airbus A380.
