Fri October 03, 2003
G.W. Hall
The days when drawbridge openings meant traffic delays for motorists on Maybank Highway between James Island and Johns Island will soon become chapters in history books alongside others in Charleston’s rich and colorful history.
By the summer of 2004, the South Carolina Department of Transportation (SCDOT) expects HDR Construction Control Corporation and Republic Contracting Corporation to complete work on a new $41.5-million structure that soars high above the river channel.
“The construction of the new Stono River Bridge is a wonderful transportation project for the Charleston Community, James Island and the Sea Islands,” said Charleston Mayor Joe Riley. “The new Stono River Bridge will benefit the residents of Johns Island, Kiawah Island, Seabrook and Wadmalaw Island by having better access to the mainland without the frequent interruption of bridge openings as was the case for many years.
“The new bridge will have four lanes of traffic — two in each direction — to accommodate existing and future traffic demand for the area, making a daily commute possible with less delay, less congestion and less frustration,” Riley added. “We also worked hard to enable motorists to see the wonderful view that the Stono River and the marshes have to offer by providing a ’see-through’ railing. In addition, the larger capacity of the bridge offers a safer and more orderly hurricane evacuation, if it should be necessary.”
The new fixed roadway bridge will stand high enough for Intracoastal ships as tall as 65 ft. (19.8 m) to pass beneath. In addition to vehicular traffic, the 90-ft. (27.4 m) wide structure will feature shared bicycle lanes, sidewalks and access over Penny’s Creek for those entering or leaving Headquarters Island, Buzzards Roost Marina and the Noisy Oyster Restaurant.
“The new Stono River Bridge presented an excellent opportunity to think about the future and to include the pedestrian and bicycle elements which often have been forgotten in the past as major transportation facilities have been built,” Riley said. “With the sidewalks and the bike lanes, citizens from Johns Island and Charleston will be able to walk across the Stono River Bridge as well as use their bicycle from Johns Island to James Island.”
As with many projects now under way in the Palmetto State, SCDOT chose to contract the construction engineering and inspection (CEI) services for the Maybank Highway Bridge Replacement and Roadway Improvement project. HDR Construction Control Corporation, the designers of record for the Maybank Highway Bridge Replacement and Roadway Improvement project, oversees the CEI services. The organization also works closely with the SCDOT District Office and the project construction team, led by Republic Contracting, to ensure that the undertaking remains on schedule and within budget.
Republic Contracting began work on the project in January 2001. When completed, the new structure will extend approximately 2 mi. (3.2 km) between the historic port city’s two well-known island communities. The completed bridge will require more than 29,000 cu. yds. (22,000 cu m) of class 30 concrete and more than 11,000 cu. yds. (8,500 cu m) of lightweight concrete. On top of that, crews will install more than 14 million lbs. (6.5 million kg) of reinforcing steel, 25,000 ft. (7,600 m) of 6-ft (1.8 m) tall bulb-tee prestress girders and more than 1.7 million lbs. (750,000 kg) of structural steel.
“The initial stage of the project involved building 75 to 80 percent of the bridge as well as an access ramp off the highway to provide access to Headquarters Island,” said Julian Seale, Republic Contracting Corp. project manager. “After completing that work, we will shift two lanes of traffic onto the bridge. The changeover in traffic should take place in November or December. We will then go back, finish the remainder of the bridge that extends from Penny’s Creek toward John’s Island and tie the new roadway into the access ramp. The final portion of the project will involve taking out the old bridge and much of the existing causeway.”
The project has presented a variety of challenges to builders. The presence of sensitive marshlands adjacent to the construction area made erosion control a key consideration. Republic Contracting chose P&L to put silt fences and other runoff control measures into place.
The bridge’s design also had to take into account the area’s history of earthquakes. Seismic (earthquake) criteria influenced decisions on the sizing and type of foundation elements, such as the bent and footings for the girder spans. The bridge’s plastic hinged supports incorporate spiral hoops for containment. In addition, seismic restrainers at joints will prevent girders from slipping off of a bent during a seismic event.
To stabilize approach ramps to the structure, designers used rock columns. Republic Contracting subcontracted the rock column work to Haywood Baker, which utilized a specially equipped Grove all-terrain crane leased from Sunbelt Rentals.
Engineers also took great care in placing bent locations for the new main span to ensure that work on the new bridge does not damage or restrict the existing bridge foundation and the navigational channel. To construct shafts and columns in the Stono River, builders used sectional barges to support construction cranes. Cranes used during the course of the project included a 300-ton (272.2 t) Manitowoc M250 Series 2, two Manitowoc 4000s, a Manitowoc 3900, three 100-ton (90.7 t) Link-Belt 218 cranes, two 75-ton (68 t) Link-Belt 138s, two Link-Belt 108s, a Link-Belt 8040 rough terrain crane and a Link-Belt 8020 rough terrain crane.
Several of these cranes worked from floating barges in the river. Republic Contracting leased the Manitowoc M250 from M.D. Moody. In addition, Case Atlantic drilled shafts for the bridge pilings with a rig mounted on a Manitowoc 4100 crane.
Other contractors employed a variety of machinery to complete their work at the bridge site. For example, Roadway contractor Banks Construction Company utilized a Caterpillar 140 motorgrader, a Caterpillar 426 rubber-tire backhoe, a Komatsu DP41 and a Komatsu 220 excavator for grading, earth-moving, and embankment work. The Charleston-based company, which has received a variety of awards for excellence in construction of asphalt pavement, also relied on a 10-ft. (3 m) Roadtec track paver, which was purchased from Roadtec of Chattanooga, TN, and Ingersoll-Rand DD110 rollers while building the new roadway. In order to remove asphalt from the existing Maybank Highway, Banks crews used a Wirtgen milling machine.
Banks Construction obtained its Caterpillar machinery from Blanchard Machinery Inc., and acquires Komatsu equipment primarily from Mitchell Distributing Company.
“We especially like our Caterpillar 426 rubber-tire backhoes,” said Rick Bryant, project manager of Banks Construction Company. “In fact, the company assigned one Caterpillar 426 to each of our work crews.”
W. Frazier Construction Inc. also assigned an impressive fleet of equipment to the project. The company relied on a Caterpillar IT28G loader, a Caterpillar 322B excavator, a Komatsu 300 excavator, a John Deere 410E backhoe, a Caterpillar D5M bulldozer, a Caterpillar 12G motorgrader, a Fiat 65C motorgrader, a 66-in. (168 cm) Bomag vibratory roller, and a variety of trucks to complete its work on the project. The subcontractor from Ravenel, SC, assisted with storm drain, grading, road widening and embankment placement.
“Our part of the project includes 30,000 cubic yards of embankment emplacement and the removal of 25,000 cubic yards of material contained in the existing causeway,” said David Barker, W. Frazier Construction Inc. construction manager. “We also put down the fossilized limestone base course for the new roadway.”
Other key subcontractors included Lowcountry Rebar, which tied reinforcing steel for the structure’s steel shafts. State Contracting of Columbia, SC, provided steel for columns, caps and decks. Cullum Mechanical installed electrical conduits in parapets and along sidewalks. Eagle Grooving cut grooves in the new traffic decks. Len Hazen Painters of Fort Ogden, FL, will paint the structure.
Together, their efforts will help to usher in a new era of traveling in the Charleston area.
“This has been a long awaited project by the citizens of Charleston and the Sea Island communities for many years,” Riley said.
This story also appears on Crane Equipment Guide.