Outstanding Underground Project

Project Name:
Exchange Place Station – 9 Car Program West Corridor

Location:
Jersey City, NJ

Shotcrete Contractor:
Patriot Shotcrete, LLC

Architect/Engineer:
WSP USA, Inc.

Material Supplier/Manufacturer:
Eastern Concrete Materials

Equipment Manufacturer:
Western Shotcrete Equipment, Inc.

General Contractor:
Walsh Construction Company II, LLC

Project Owner:
Port Authority of NY NJ

Honorable Mention Project

Project Name:
Pennsylvania Turnpike Commission – Tuscarora Tunnel Rehabilitation

Location:
Burnt Cabins, PA

Shotcrete Contractor:
Mosites Construction Company

Architect/Engineer:
Gannett Fleming Inc.

Material Supplier/Manufacturer:
New Enterprise Stone & Lime Company Inc.

Equipment Manufacturer:
King Shotcrete Equipment, Inc.

General Contractor:
Mosites Construction Company

Project Owner:
Pennsylvania Turnpike Commission

Honorable Mention Project

Project Name:
Atlanta Airport Plane Train Tunnel- West Extension

Location:
Atlanta, GA

Shotcrete Contractor:
Guy F. Atkinson Construction

Architect/Engineer:
McMillen Jacobs Associates

Material Supplier/Manufacturer:
Master Builders Solutions Admixtures US LLC

Equipment Manufacturer:
Normet Americas, Inc.

General Contractor:
Clark Construction Group

Project Owner:
City of Atlanta/Department of Aviation

South Wastewater Treatment Plant

I n early September of 2019, Gulf Coast Underground (GCU) received a call from the City of Baton Rouge and their construction manager, Jacobs Engineering Group (JEG). There was an issue at the South Wastewater Treatment Plant that would require a unique contractor skillset to properly repair. The problem was that the cast-in-place influent structures receiving 65 million gallons (246 ML) of sewer flow daily, were corroding and needed to be repaired quickly

Park Avenue Tunnel Rehabilitation

The Park Avenue Tunnel, formerly known as the Murray Hill Tunnel, is a 1,393-foot-long (425 m), 16-foot-wide (5 m), 9-foot-tall (3 m) thoroughfare traversing six New York City blocks. The tunnel was originally constructed in 1837 as an open rock-cut, with a brick arch constructed over the cut in 1854 to create the tunnel profile. For the next 150 years, the tunnel would be plagued with issues ranging from mechanical system failures to liner wall leakage due to the soil volume above, which is where the idea of shotcrete stabilization was introduced within the project scope.

Poe Tunnel

When you are faced with a project with limited access, material delivery by helicopter, the nearest personnel access is 5 miles (8 km) away, and the closest outside access to the shotcrete placement location is a half mile away, the only solution to handle all of these issues is shotcrete. The Poe Tunnel is a 15 mile (24 km) long tunnel in the foothills of the Sierra Nevada Mountains and is in an area of steep canyons. The tunnel transports water from a forebay on the North Fork of the American River to the Poe Powerhouse where electrical power is generated. The tunnel is almost 20 ft (6 m) in diameter and was constructed in the 1950’s.

I am working on a project that has existing tunnels made with shotcrete. I am needing to hang 12 in. (300 mm) duct and trying to figure out the best type or suggested anchors to use.

Shotcrete is just a placement method for concrete. Shotcrete placement with proper materials and application techniques should provide monolithic concrete with a 28-day compressive strength of at least 4000 lb/in2 (28 MPa). Thus, any systems that work in concrete should be fine. Either mechanically-fixed or epoxy-set anchors are commonly used in concrete. You should consult with the anchor suppliers for the size and type of anchor appropriate for your specific application.

The Value of VR Training for Today’s Shotcrete Nozzlemen

Recruiting, training, and retaining skilled shotcrete nozzlemen is mission-critical for a company’s success. Virtual, immersive training offers an effective, engaging mode of learning that supports the modern trainee. For beginning nozzlemen, virtual reality training gives them a safe, repeatable experience that can be completed in a classroom, free of job costs. Practice without cost or risk also helps improve job performance and satisfaction. These disruptive virtual reality (VR) technologies can provide safe, hands-on learning experiences without the field costs associated with hands-on training. Virtual learning is also valuable in today’s socially distanced world with its shifting remote learning requirements. Interactive digital tools will deliver meaningful, adaptive training for skilled trades now and in the future. Though some level of hand nozzling experience is still needed the best nozzlemen will be trained, in part, using virtual reality.

Encapsulation of Reinforcement in Tunnel Shotcrete Final Linings

Using shotcrete for the placement of concrete for tunnel final linings is becoming more common. In the past the use of shotcrete final linings was typically limited to non-public or emergency egress areas, however, shotcrete is being used more and more in public areas. The use of shotcrete is typically an attractive alternative to form-and-pour final lining installation where formwork costs are high or technically challenging, pose a scheduling issue, or where labor rates are very high. Typical examples for successful use of shotcrete final linings are complex lining geometries, intersecting or merging tunnels, widenings, short tunnels without sufficient repeating utilization of the forms, or underground systems where formwork would block passing traffic.

Mechanical Application of Shotcrete in Underground Construction

The manual hand application of shotcrete began over 100 years ago and continues today in a wide range of applications and projects. To provide a proper distance of the shotcrete nozzle tip to the underground surface wall, surface receiving shotcrete or ‘substrate,’ the hand application of shotcrete in larger diameter underground structures required the nozzlemen to operate from a man-lift or similar equipment. Working from elevated platforms and the close proximity of the nozzleman to the substrate added safety challenges to projects. Thus, as more underground projects started to use the wetmix shotcrete process, spraying shotcrete with mechanical arms began to address these safety concerns.