The historic Reedy River in Greenville, SC, and its waterfalls were originally a source of power for a grist mill in an early settlement that eventually became the city of Greenville. Over the years, the river had deteriorated into an eyesore, especially during the past century. But with the approval of a $12.5 million budget for a new park in downtown Greenville, the Reedy River has been restored to its former glory. The city of Greenville contracted CSDA contractor member E. Luke Greene Company Inc., of Johnson City, TN, to help make this happen.
The first step in the undertaking to create a new park and garden was the removal of the Camperdown Way Bridge; a 406-ft. (124 m) long, 68-ft. (21 m) wide bridge built 48 ft. (15 m) above the Reedy River. The removal of the bridge would make the Reedy River Falls visible for the first time in more than 40 years.
Concrete cutting was specified for this high-profile job because the job site was located in downtown Greenville, so there could be no dust or excessive noise that could disrupt the town’s patrons. Understandably, slurry in the river and riverbed was a primary concern. The riverbed could not be disturbed, the river flow could not be altered, and all surrounding plants and trees were to remain untouched. Conventional demolition methods, such as breaking or explosives, could not be used due to these strict environmental standards and laws.
Other factors complicating this job included an uneven terrain, the water level of the river, slurry containment under the bridge and making sure the old grist mill walls were protected.
E. Luke Greene Company was selected as the general contractor for this project because of its experience in bridge demolition work and the company’s in-house concrete cutting capabilities.
The bridge was composed of seven 58-ft. (18 m) spans, resting on five piers and two abutments. E. Luke Greene Company’s job was to dismantle the bridge, primarily utilizing concrete sawing to cut the structure into manageable pieces.
The crew began this undertaking by removing all traffic lines and markings on the bridge deck using the Lead Abatement Division. The next step in the process was the removal of the concrete bridge deck spans. Each span was composed on 11, 30-in. (76 cm) steel I-beams, the bridging between them and the concrete deck.
The removal sequence required operators to saw cut the concrete deck with flat saws and lift out every other section between beams, leaving pairs of beams with the concrete decking still attached. The pieces were lifted by a 200-ton (180 t) crane, which was situated on the span adjacent to the span being removed.
As operators dismantled the first span, the crane rested on the end of the second span. Once operators completed dismantling the first span, including piers and footings, they moved the crane to the third span, and so on until the entire structure was dismantled.
One factor that complicated this process was that between each span there was an expansion joint compound that had an asbestos base. To avoid sawing into this compound, operators drilled 10, 12-in. (30 cm) diameter holes in each span in the section of the deck adjacent to the expansion joint. This allowed it to be released, but did not disturb the asbestos. E. Luke Greene’s Asbestos Abatement Divisor then removed the compound from the slab before transporting it to the recycling site.
To remove the 6- to 10-in. (15 to 25 cm) thick concrete decking between the steel I-beams, operators placed and anchored prefabricated I-beams with lifting eyes to prevent the slab from falling out. As operators completed sawing on each section, the decking was lifted with the crane, loaded and transported from the site. E. Luke Greene personnel then removed the remaining concrete deck pieces still attached to the main structural I-beams. These pieces were each 8.5 ft. (2.6 m) wide, 60 ft. (18 m) long and weighed up to 92,000 lbs. (41,730 kg).
All concrete and steel from this project was removed in large sections and transported by an excavator equipped with a multi-processor and recycled.
To control slurry during the bridge deck cutting process, E. Luke Greene sealed all the deck drains and limited water use. The company also directed the flow of the slurry to vacuums that pumped it into drums where the water was separated from the particulate matter. The water was then drained to the sanitary sewer via hoses for further treatment and the particulate matter was dried and disposed of as solid waster. This process captured 97 percent of the slurry.
After completing the removal of each span of the bridge deck, E. Luke Greene began to remove the piers. The contractor assembled mast climbers (motorized scaffolding) on both sides of the center pier to a height of 50 ft. (15 m) and a width of 63 ft. (19 m).
Operators used two Diamond Products wall saws to cut the piers into manageable pieces, each weighing up to 29,000 lbs. (13,154 kg) and measuring 14 to 20 ft. (4 to 6 m) in length. Each piece was rigged to the crane with chokers or fabricated lifting plates and loaded onto trucks for removal. Operators left a 15-ft. (4.6 m) section of each pier attached to the footer. They controlled slurry during this process using tarps and vacuums.
The last step before dismantling the next span was to remove the footers. E. Luke Greene personnel accomplished this by rigging a snatch block and cable to each remaining 15-ft. (4.6 m) section of pier and footer. These were pulled over with the 200-ton (180 t) crane to extract the footers from the ground. Crews then removed the piers from the footers using wall saws and removed the footers from the riverbed using a crane.
The concrete cutting tools E. Luke Greene utilized for this job included the Diamond Products FZ Wall Saw System, Diamond Products CC7200 and CC6500 flat saws, Partner and RGC handsaws, and Diamond Products hydraulic core drills.
Other equipment used on this job included American Mast Climbers motorized scaffolding, a Kobelco 330 excavator with an Allied-Gator multi-processor, and four 55-gal. (208 L) Crusader slurry vacuums. E. Luke Greene also fabricated I-beam spreaders and an I-beam and channel frame to mount the mast climbers to the bottom of the concrete piers.
According to E. Luke Greene’s Chris Rhyne, concrete cutting supervisor, and Mike Byrum, demolition supervisor, the most demanding aspects of this job included set up and dismantling of the mast climbers, slurry control and containment, and strictly adhering to fall protection and lifting safety regulations.
“The most satisfying aspect was the way the various disciplines within our firm pulled together to complete this demanding project successfully,” Rhyne said.
E. Luke Greene completed this job within budget and in 78 days, which was 12 days ahead of schedule. The company cut a total of 1,472 yds. (1,346 m) of concrete, 761,000 lbs. (345,183 kg) of structural steel and 226,020 lbs. (102,521 kg) of reinforcing steel. Operators removed a total of 5.9 million lbs. (2.2 million kg) of concrete to help restore the Reedy River’s natural beauty.
E. Luke Greene Company Inc. has been a CSDA member since 1998. It employs two CSDA Certified operators. The company has provided demolition and related services since 1983, having completed more than 4,000 jobs as of Jan. 1, 2002. Its services include basic demolition, selective demolition, industrial/mechanical demolition, concrete sawing and drilling, asbestos and lead removal, industrial concrete installation, structural shoring and roll-off container service.
For more information, call 423/926-1151.
(This article appears courtesy of “Concrete Openings.”)