HDD for GCRTA project

HDD Integral to GCRTA Waterfront Line Bridge Repair Work

McLaughlin MCL 10H using 28-in. long Firestick drill rods

Cleveland-based contractor The Vallejo Co. was contracted by The Great Lakes Construction Co. to horizontal directional drill (HDD) a series of bores that would play a pivotal role in a bridge rehabilitation project for the Greater Cleveland Regional Transit Authority (GCRTA).

The goal was to stabilize a bridge along GCRTA’s Waterfront Line, which plays an integral role transporting riders to major tourist attractions.

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When it comes to trenchless and light rail work, the trenchless scope is usually focused on installing or repairing pipes underneath the tracks. This recently completed project by The Vallejo Co. bucks that trend.

How did Vallejo get connected on such a unique project?

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Mark Adzema, P.E., vice president and COO, says it was a phone call from a fellow contracting firm that started things off.

Before moving forward, it’s best to understand how the overall project came to be.

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The GCRTA Waterfront Line Closure

The GCRTA Waterfront Line was opened in 1996 as part of the City of Cleveland’s bicentennial celebration. The line shuttles riders from Tower City — a shopping and entertainment hub that is part of Cleveland’s Terminal Tower complex — to Cleveland’s South Harbor. Notable destinations along the route include the East Bank of the Flats residential and entertainment district, Cleveland Browns Stadium, the Great lakes Science Center, Rock & Roll Hall of Fame and the Goodtime III pleasure cruise boat.

Though initially running a full seven-day schedule, in the last decade, the line has seen only weekend and special event service. In 2018, GCRTA completed an extensive inspection of the Waterfront Line Bridge, which carries riders over the East Bank, Front Street and a set of Norfolk Southern rail tracks to the Port of Cleveland property on the other side.

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In 2019, GCRTA began to monitor stress cracks flagged by the inspection and began to limit stress on the bridge by restricting traffic to one car crossing at a time. In 2020, Waterfront Line service was suspended due to a Tower City track rehabilitation project. In the Spring 2021, GCRTA hired Hardesty & Hanover to complete a second inspection before returning the line to service.

As a result of this inspection, it was recommended that four temporary support towers should be constructed to stabilize the bridge. It was also recommended that the train service remain suspended until a permanent fix could be made.

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Hardesty & Hanover worked to design the permanent repair for the segmental bridge, with an estimated return to service expected in Fall 2023. The Great Lakes Construction Co. was selected as the general contractor to oversee the rehabilitation and improvements to the bridge.

The embankment on each side of the bridge — from the East Bank of the Flats to the Port of Cleveland Property — is supported by mechanically stabilized earth (MSE) retaining walls.

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“The main purpose of the project was to repair the segmental bridge. The existing post tension strands in the bridge were no longer adequately supporting the loads on the bridge and additional longitudinal post tension strands were added throughout the entire bridge to give the structure the additional strength to support the loads from the GCRTA trains,” says Mike Wilkinson, project engineer for Great Lakes Construction. “The MSE Wall Repairs were an additional item included in the project because several areas on the walls were in bad shape and instead of waiting until the point of failure the GCRTA determined that this would be the best and most cost-effective time to repair the walls, as well.”

The Vallejo crew used a McLaughlin MCL 10H using 28-in. long Firestick drill rods.

Going Trenchless in the Air?

This is where Vallejo and its HDD expertise come into play.

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Hardesty & Hanover and GCRTA officials looked at several options to repair the MSE walls. The most expensive would have been the complete replacement, which would have greatly extended the length of the project. Instead, the team landed on the idea of boring through the walls and under the tracks at several spots, inserting post tensions strands through the bores and anchoring them to the wall and pouring a new concrete face.

“They decided to go with this repair method because it was the most cost-effective and was more aesthetically appealing than the other repair options,” Wilkinson says.

Adzema refers to the project as “a little bit of a curve ball” that ended up in his lap. The bulk of Vallejo’s HDD work is more run-of-the-mill work for local natural gas companies, telecoms and smaller diameter sewer and water work.

“I worked for another firm for 31 years and Great Lakes reached out to it initially because they do directional drilling work. One of the project managers there got in touch with me to see if I’d be interested,” says Adzema. “I asked him to send me the plans, looked them over and I came up with an idea in my head. The question was, ‘How would we do a drill shot in mid-air?’”

Adzema has done some work with a pit-launch drill, and he surmised that that machine would be the only one capable of completing the task. “Normally, we use the machine for water service connections in tight areas where a pneumatic mole won’t work because of the length of the bore and a traditional HDD doesn’t have space,” he says.

Adzema reached out to his contact at Vermeer and explained what his idea was — boring 20 ft in the air, 45 ft across and pulling back a 6-in. HDPE pipe. Vermeer said that the 5-ft version of a McLaughlin MCL 10H using 28-in. long Firestick drill rods that Vallejo planned to use would be capable of this work.

He submitted his idea to Great Lakes Construction, but it would have to figure out what kind of structure could be manufactured to get the drill safely to the proper height and still be able to handle the push and pull forces on the machine.

“The biggest challenge Great Lakes Construction and Vallejo had to overcome was developing a plan that would allow their drill rig to reach all the various hole locations. The holes ranged anywhere from 1-ft to approximately 20 ft off the ground. Figuring out a way to allow Vallejo to move their drill rig and personnel from location to location in a quick and efficient matter was critical to having a successful operation,” says Wilkinson. “Eventually we all agreed that placing the drill rig on a platform and mounting that platform to a piece of equipment [in this case a telehandler] was the most practical way to complete the work. However, there are no off-the-shelf platforms for this type of work. We had to find a fabricator to make a custom platform. That was easier said than done. After several months of searching, we were able to coordinate with Blue Ridge Forge and we worked together to develop a custom platform for this operation.”

Adzema notes that while there were some other project challenges, tackling this elevated platform to mount the pit-launch drill was the biggest one. However, once they were onsite to perform the work another issue quickly became evident: How could they effectively locate where the drill bit is?

Josh Spray, the local DCI territory manager, gave Vallejo the idea to target bore.
The DCI DigiTrak F2 Was set on a platform above the exit side and the Vallejo crews used target boring due to the interference. All of the bores exited on target.

Exiting On Target

“We were 20 ft in the air, between two concrete reinforced walls that have galvanized strapping running from wall-to-wall, metal railroad tracks and then catenary lines above,” Adzema says. “How would we get a good signal to our DCI receiver? Josh Spray [the local DCI territory manager] gave us the idea to target bore.”

To accomplish this, the Vallejo crew set up their DCI Falcon on the opposite side of the bridge and approximately 18-in. above the centerline where the bore needed to exit. Adzema notes that they were able to get great readings and all bores were completed on-target.

“I wasn’t sure that would work, and it did. Between Great Lakes’ planning, and design of the platform — which set us up for success — and Josh’s suggestion to target bore, the project went a lot smoother than I thought it would,” says Adzema.

He adds, “I’ve been around directional drilling for 31 years. It was unusual, but it wasn’t anything I was nervous about because I knew the equipment could do it. I do have to say you have some ingenious people at Great Lakes who came up with some ideas. They saw the vision I had and made it happen. It’s always rewarding when you envision it, and you make it come to life successfully.”

The Vallejo crew, at far left, assists in preparing for pullback.
When the bores were complete, the Vallejo crew pulled back the HDPE pipe that would serve as the backbone of the wall stabilization project.

The work was completed in two phases from March 23 to May 25 and the 23 shots went smoothly. The work consisted of a 9-in. initial pass using a standard reamer and pulling back 6-in. HDPE sleeves.

From there, Great Lakes Construction formed and poured new concrete-faced walls and extended the holes through to walls. The stabilization work was completed by DYWIDAG, which pulled a 1-in. diameter rod through the HDPE sleeve, capped the rods, and stressed the bar to capacity to retain the walls. To complete the project, the annular space was grouted and capped.

“Overall, the directional drilling was very successful. There were some minor hurdles that had to be overcome — for example, hitting MSE wall straps and other obstructions and relocating numerous tieback/hole locations due to utility conflicts — but Great Lakes Construction, Vallejo, the GCRTA and Hardesty & Hanover were all able to work together as a team to get through all the obstacles and make this a successful project.”

So successful was the work that the GCRTA was able to officially host a ribbon cutting to reopen the Waterfront Line on Sept. 5. Passengers were able to ride the rails Sept. 10 from Tower City to South Harbor — the stop closest to Cleveland Browns Stadium — to watch the Cleveland Browns season opening trouncing of the Cincinnati Bengals.

Mike Kezdi is the managing editor of Trenchless Technology.

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