Contractors and developers are pushing the speed limit to finish the newest National Hot Rod Association (NHRA) drag strip in time for a national racing competition slated to begin on Sept. 11. With a $50-million-plus price tag, the new zMAX Dragway @ Concord is not just another drag strip on the NHRA circuit. Situated on 125 acres of land adjacent to Lowe’s Motor Speedway in Concord, North Carolina, it will be the first four-lane, all-concrete facility in the United States.

Much effort has been given to the track’s design, which has evolved since the beginning of the process in an effort to elevate the sport of drag racing by providing a venue that is fan-friendly and conducive to competitors alike. The zMAX Dragway is owned and managed by Speedway Motorsports, and CEO Bruton Smith calls it the “Bellagio of drag strips.”

Building this “Bellagio” in time for the NHRA Nationals required a sitework contractor who could face the challenge of a tight schedule--and even tighter tolerances. Hoopaugh Grading Co. of Charlotte won the bid for the grading and sitework and has been preparing the site for the drivers and the fans.

Fuel costs increased $1 per gallon after Hoopaugh began working on the zMAX site; the contractor continued using its Volvo fleet for its fuel-efficient operation.

Racing to Stay on Schedule

Hoopaugh Grading Co. has been doing sitework in the Charlotte area for more than 50 years. In the past six years, the company has grown exponentially and its fleet has increased from 30 pieces of earthmoving equipment to well above 100. Currently, Hoopaugh employs more than 100 people, including in-house surveyors and engineers. When construction began in January on the zMAX Dragway facility, Hoopaugh’s crews joined with the other contractors onsite.

“It’s a very aggressive schedule,” says Jeff Black, project manager for Speedway Motorsports. Approximately 400 people have been working six to seven days a week on different stages of the project, which has an accelerated schedule that is approximately two-thirds of the normal construction timeline for a project of this size.

Owner Larry Hoopaugh says, “Our biggest concern in the beginning was the schedule. It’s the nature of the racetrack business to change and add to a project. The first drawings were very preliminary, and we were going from week to week getting updated drawings. However, there is no change in the drop-dead date.”

The Dragway’s original design included two racing lanes, grandstands, a pedestrian tunnel and a starting line tower more than 54,000 square feet in size, which houses luxury suites, a control area for racing officials and a broadcast booth and press box. Design changes have included additional grandstands, a second pedestrian tunnel and, most notably, the addition of two more racing lanes. “Our facilities at zMAX Dragway will be a step above, due to all the amenities and fan-friendliness of the venue,” Black says.

The quarter-mile racing lanes will be concrete with an additional 2,680 feet of asphalt and a 200-foot sandpit at the end. In all, the drag strip will be approximately 4,000 feet long--the equivalent of 13 football fields. “Even with all the design changes we’ve had along the way,” Black adds, “we are right on schedule.”

Soil Smarts

Although the dragway is not the largest project Hoopaugh Grading Co. has undertaken, it is definitely the most challenging. Larry Hoopaugh and partner Brian McManus’s expertise with the area’s site proved to be a benefit for his company and for Speedway Motorsports. Much of the area’s soil is pit gravel with some silt and clay. Hoopaugh says the area had previously been excavated for a nearby landfill, so he was familiar with the area and knew what type of soil to expect. “There is a lot of very dense soil out here,” he says. “The more dense the soil, the better the subgrade. There is not as much settlement and we use less rock.”

Black agrees, noting, “Hoopaugh thoroughly did its homework during the bid process back in January.”

For the earthmoving, Hoopaugh’s fleet of equipment on the jobsite includes mostly Volvo provided by ASC Construction Equipment of Charlotte. With the surge in oil prices, Hoopaugh’s fuel costs increased by $1 per gallon after the project began. Hoopaugh says the Volvo fleet is the most fuel-efficient equipment he owns, so his crews continued using it at the zMAX site.

Hoopaugh utilized a dozen Volvo A30D and A40D articulated haulers, a Volvo EC210 crawler excavator and a Volvo L110E wheel loader. Hoopaugh also used a Volvo EC700 excavator--the largest excavator in Volvo’s product line--for the first three months to do much of the heavy earthmoving. “The Volvo EC700 was instrumental in getting us ahead with such an aggressive schedule,” he says. “Much of the ground out here is very hard and dense and the EC700’s power and size enabled us to keep production high.”

Hoopaugh estimates his company has moved approximately 800,000 cubic yards of dirt and 200,000 cubic yards of rock. Hoopaugh’s knowledge of the area’s soil composition gave his company a big advantage for the grading take-off. He knew there was plenty of subsurface rock that could be excavated and that rendering the rock could be done onsite. He was right--nearly 300,000 tons of rock have been excavated and crushed onsite, saving the project more than $1.5 million in costs.

Red Clay Industries operates the crushing operation, using the northeast end of the jobsite as a quarry. Red Clay moved in a Powerscreen mobile cone crusher and uses a Volvo EC240 demolition excavator with a BTI breaker to break up the rocks and Volvo L150 and L220 wheel loaders to load the rock into the crushing machine. “We crushed between 3,000 and 4,500 tons of rock per day,” says Jim Smith, president of Red Clay Industries.

All of the site rock was crushed to aggregate base course (ABC) and used as the final sub-base layer before paving. Good weather and soil conditions helped the project stay on schedule. Much of the soil at the dragway filters water, so there is very little standing water. Hoopaugh didn’t have to contend with high groundwater; the deepest cuts were 15 feet at the pedestrian tunnels. Some groundwater needed to be pumped out after those cuts, but moisture has not been an issue otherwise. A dewatering system was incorporated into the design to tie into the current stormwater system.

To move the pit gravel, sand and clay, Hoopaugh utilized a dozen Volvo A30D and A40D articulated haulers.

Tight Tolerances

After the heavy work was completed, Hoopaugh’s crews began staging for the fine grading and laying the sub-base prior to concrete and asphalt paving. Specifications for paving were very precise, although weight on the track did not factor in. The sub-base was still very crucial because any settlement could potentially cause an uneven track. The specifications for density of the sub-base were 95% compaction, based on international ASTM standard D698 Moisture-Density Relationship, with the final foot at 98% compaction. Specifications called for 8 inches of ABC crushed rock to be laid underneath 6 inches of concrete for the racing section of the track.

“Those race cars are like airplanes,” Hoopaugh says. “If there is any differential when cars are traveling that fast, they could essentially lose contact with the pavement. The tolerance will have to be so close.”

Speedway Motorsports hired ESP Associates, headquartered in the Charlotte metro area, to provide special inspection and testing services. ESP performed all soil monitoring and compaction testing, and documented the results to satisfy the county and city inspectors.

“We had as many as three engineering technicians for soil testing at the jobsite at a time during the earthmoving phase,” said Brian Welch, division manager with ESP. “Typically, we have one to two technicians on a job, but because of the fast pace of this project, we needed three people out there at times to keep up with the grading contractor’s production.”

Welch explains the two-step process to monitor soil compaction. First, after the vegetation was stripped away, the contractor conducted a “proof roll,” which consists of moving a loaded dump truck or pan excavator over the area to look for signs of ground instability.

After each 12-inch lift of fill soil was placed and compacted, the soil was tested for compaction. This process used the “drive-tube method.” A hollow metal tube was driven into the ground to collect a soil sample. That sample was then weighed and dried to determine its dry density, then compared to laboratory test results to determine its relative compaction. According to Welch, 95% compaction is relatively standard to control settlement; however, it was determined the final foot should be at 98% for a more rigid subgrade.

The county and city of Concord have been doing routine inspections, but according to Welch, with the aggressive schedule, city inspectors relied mostly on ESP to do much of the monitoring and inspections.

“We made available to city and county inspectors copies of all our daily reports,” he said. “It really helped with the efficiency of the job.”

Green Light Ahead

“This job has definitely been a team effort,” Hoopaugh says. “My partner Brian, along with our operations manager Paul Heape, job superintendent Steven Parker, and foremen Chris Robinson, Tony Duncan and Rick King deserve most of the credit for our accomplishments on this project.”

With the finish line in sight, Black feels very confident that the green light will flash on Sept. 11. “Speedway Motorsports is constructing the best NHRA drag racing facility that’s ever been built,” he says, “and we’re going to build it in the shortest time frame.”


Manufacturer Information

BTI, www.rockbreaker.com
Powerscreen (a Terex Company), www.powerscreen.com
Volvo Construction Equipment, www.volvoce.com

Sidebar: zMAX Dragway @ Concord Fast Facts

zMAX Dragway @ Concord is the only all-concrete, four-lane drag strip in the United States, and only the third all-concrete quarter-mile on the NHRA POWERade Drag Racing Series circuit.

A pair of two-lane strips, located side-by-side, allows for a variety of opportunities including specific track preparation for different vehicles, racing four cars at a time, and the possibility for racing to continue in the event of an oil-down that requires extensive cleanup to one of the lanes.

The drag racing facility’s track, pit areas and midway cover 46.5 acres, or 2 million square feet.

The dragway surface is smooth and there are no transitions, which could lead to record-breaking race times when the NHRA Nationals begin.

The NHRA Nationals will be held at zMAX Dragway @ Concord Sept. 11-14. The playoff round will begin when the top 10 competitors in all four professional categories--Top Fuel, Funny Car, Pro Stock and Pro Stock Motorcycle--compete in the six-race NHRA POWERade Countdown to the Championship and race for the chance to be crowned NHRA POWERade world champions.


Source: www.Lowesmotorspeedway.com