When work on the $1.4 billion North Tarrant Express 35W, a reconstruction of Interstate 35W in Fort Worth Texas, required moving more than 150,000 tons of fill material across the interstate, the road builder North Tarrant Infrastructure (NTI) turned to McCourt & Sons Equipment for a cost-effective solution. 

 "There was traffic and the need for relocation of the materials," says Colin Keane, Sales Manager at McCourt & Sons in LaGrange, Texas, which came up with a two-part conveyor system as a proposed solution to efficiently bypass various traffic obstacles.

"The conveyor system proved to be very innovative for our project, providing a safer and more reliable way to move fill," says Heather DeLapp, a Spokeswoman with Ferrovial Agorman, a contractor partner with North Tarrant Infrastructure. 

NTI, a joint venture between Ferrovial Agroman US Corp. of Austin, Texas, and Webber of The Woodlands, Texas, is rebuilding the southern portion of the 10-mile I-35W corridor in the northeast Fort Worth area for NTE Mobility Partners 3, the concessionaire, which is operating the highway on behalf of the state. NTI is self-performing only a small portion of the work, so local and regional subcontractors and suppliers are heavily involved, which helps stimulate the local economy.  

The project includes reconstructing the general-purpose lanes and existing frontage roads and adding four TEXpress managed lanes, with variable tolling based on traffic conditions. The Texas Department of Transportation (TxDOT), which will continue to own the road, expects the project to relieve traffic congestion on the highway and enhance safety. The highway, a major north-south route, was built in the 1950s and 1960s and is ranked 23rd on the state's most congested roadway list. 

The corridor is one of several public-private partnership highway projects in the state. Construction began in 2014 on the southern portion, Segment 3A. NTE Mobility Partners 3 is designing, building, financing, operating and maintaining the 6.5-mile southern segment under a 52-year concession agreement. 

"Within our project limits of I-35W 3A, we divide our work area into north and south segments, and then into four sub segments, so that all work can occur concurrently," DeLapp explains. "And 100 percent of the roadway is under construction." 

NTI reports that more than 1,200 people work on the site each day, and the project has logged roughly 4.4 million man-hours with a 1.0 safety incident rate. 

To the north, Segment 3B, financed and built by TxDOT, is substantially complete and will be operated by and maintained by NTE Mobility Partners 3. 

The Unique Solution

NTI sought a solution for relocating the material on the south segment of I-35W 3A, from 33rd Street to I-30.

"The original idea was to balance earthworks between the sub segments; however, the timing for the phasing did not match. Having traffic cross in the middle of our work area made it impossible to haul the material in a straight path so the conveyor system overcame this challenge," DeLapp explains. 

NTI initially considered using haul trucks to transport the fill, but that would have entailed 25-ton trucks and 6,000 truckloads on an already congested roadway.

"Given the roadway configuration it meant longer distances, less performance, higher costs, traffic disruptions and safety threats for both drivers and production personnel," DeLapp says. 

Bucky Graue, Territory Manager for McCourt, who initially worked on the conveyor system solution, points out that truck hauling "was going to incur a lot of fuel costs and add traffic to the area. It was not a very practical solution."

Representatives from NTI asked McCourt if it could come up with another alternative. After several meetings to learn more about the project and its parameters, McCourt proposed a conveyor system, which included a McCloskey 48-inch by 80-foot Tracked Feeder Stacker, which would feed a Superior 42-inch by 120-foot Zipline Conveyor that would be elevated over I-35W within an enclosed platform.

The enclosure, which Keane describes as a type of bridge, was a vital component of the conveyor system because "inside an enclosure, there would be no spillage onto the traffic passing below."

NTI liked that idea. McCourt would install the stacker and conveyor. NTI took on the responsibility to build and erect the elevated, enclosed platform that would support the conveyor. Graue described it as a type of bridge. 

The McCloskey tracked feeder stacker features a counter-weight design. It comes equipped with a 7.5-cubic-yard capacity feed hopper and a belt. The 62,850-ton unit is on tracks and can be set up within 10 minutes by one person and no tools. It can move up to 1,000 tons of fill material per hour.

The Superior Zipline, a pre-engineered, modular overland system, is designed for quick, tool-free and simple installations. The system uses a fixed-pin connection and is set up by hooking each section together. The Zipline moves 450 feet per minute and can process 1,500 tons of fill material per hour. 

Once the conveyor system was in place, North Tarrant crews used excavators to load the hopper on the feeder stacker, thereby moving more than 600 tons per hour. 

"That ended up much more effective and efficient than the trucks," Graue says. "It worked so well, NTI is relocating the two conveyors to a different location on the I-35W project."
 
 Responsive and Reliable

McCourt & Sons was established in 1999 and serves customers throughout Texas, Arkansas, Louisiana, Oklahoma, New Mexico, Wisconsin and Mississippi. It represents 12 manufacturers of new equipment, including McCloskey International, Superior Industries, Telsmith, Lippmann-Milwaukee, CDE Global and Cemco Turbo, MDS International, Doppstadt, Backhus, Backers, Tiger and Harvest Quest.

McCourt sells and rents portable and stationary crushing equipment, screening equipment, conveying equipment, recycling, grinding, shredding, washing and recycling equipment. The company continues to invest in additional equipment, stocks more than $4 million of parts and components, and maintain five parts support vehicles, 10 field service vehicles and four haul trucks. Support is available 24 hours a day, seven days a week. 

"We pride ourselves on being able to provide responsive and reliable product support," Keane stays. "McCourt has positioned our business to respond to short- and long-term rental and sales requirements by general highway contractors. We do a tremendous amount of work in heavy highway construction."