Remodeling will be step up for century-old courthouse
There was no footing or foundation beneath the first of three staircases.
It seemed like a fairly routine project – fixing the staircases outside the historic Luzerne County Courthouse – until contractors removed the granite steps.
Nobody knew what to expect because the opening beneath the stairs hadn’t been visible since the structure was built a century ago.
Contractors found there was no footing or foundation beneath the interior support walls on the north side, which is the first of three staircases that will be repaired. Instead, the walls sat on concrete pilings tied to bedrock 15 to 20 feet below the surface.
Additional support walls are needed to hold the weight of the granite steps and prevent them from settling again, but there wasn’t any way to lay foundation for the new walls because the fill beneath the steps is “junk material” – ash, railroad ballast, leftover brick from the courthouse construction, said county Chief Engineer Joe Gibbons.
Architect Carl Handman touches peeling paint on a window sill of the historic Luzerne County Courthouse.
Workers Scott Gryczka and Tom Davis build walkways on the roof of the Luzerne County Courthouse for a restoration project.
The site had served as a canal holding basin and then a railway before the courthouse was built in 1909, said project architect Carl Handman.
The solution: the new support walls will be placed on “helical piles,” a new technology, Gibbons said.
Helical piles are rods with a sharp bit on the bottom. They will be hooked to a backhoe with a special machine that screws them through the dirt and into the bedrock, he said. The new walls are then placed on top of the new piles with rebar.
“We transfer these entire loads right down to the bedrock because the soil is no good,” Gibbons said.
The granite steps, each about 12 feet long and 1,000- to 1,500 pounds – were removed using a specialized piece of equipment acquired by the project contractor, D.A. Nolt Inc., if Berlin, N.J.
It’s basically a large suction cup that uses pressure to grip the pieces, allowing them to be lifted and moved without damaging them, Gibbons said. The steps, also called treads, are not reinforced and could crack if they’re jostled around by heavy equipment, he said.
“You really have to be careful lifting these up, and we obviously want to put them back when we’re done because they’re historic pieces of the courthouse,” Gibbons said.
Finding a match for a broken step would be difficult because the rock was mined from a quarry a century ago, and it’s doubtful any rock would be left from that seam, he said.
“We wouldn’t want to have a piece that stands out like a sore thumb,” he said.
A new drainage system is also being added under the stairs to stop water from pooling, Gibbons said.
Exterior stair repairs were added to the latest phase of the courthouse restoration project after the county building and grounds department noticed some settling of steps, Gibbons said.
The staircases at the eastern and southern courthouse entrances will be refurbished after the north side is completed, he said.
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