When the construction project straightening I-195 in Providence, RI, is finally completed in 2012, traffic will be able to zip through the city at a much faster pace than it has ever been able to before. But the process needed to make that possible is a long, arduous one.
One thing making it so slow is that a new bridge being built across the Providence River is being constructed in Quonset, 20 mi. to the south along the shores of Narragansett Bay. The 2.75-ton (2.47 t) structure will then be placed on three barges and then moved north to its permanent location.
It will only take one day to do the actual transport when temperatures warm this coming May and one other day to drop that part of the bridge. That will seem like nothing when compared to the two-and-a-half years needed to put everything together before that monumental moment. Another 30 days will be needed to load it onto the three barges that will be required.
Although only one day will be needed to place it, the process will require a great deal of precision and skill, as Kazem Farhoumand, department chief engineer of the Rhode Island Department of Transportation (RIDOT), explained: “We will be using hydraulic dollies and we will jack the bridge during high tide, then wait for low tide and then remove the barges.” (The piers, pier jacks, abutments and walls will already be in place before the signature bridge arrives.)
Farhoumand added that all the substructure and concrete portions of the bridge will be done at the Quonset location, while the remaining steel tubs will be completed in Connecticut.
Once the steel frame is put into place, the concrete deck will be added. That part of the work cannot be done before it is transported because it would be too heavy to move. The feature span will require 12,000 cu. yds. (9,120 cu m) of concrete.
After the deck is poured, remaining work includes installation of pylons, guardrails and lighting.
Cardi Corporation of Warwick, RI, is the contractor in charge of the bridge construction. It is just one of five contracts that the company is working on, most of which deal specifically with bridges throughout the city.
“It is a pretty impressive job,” said Cardi Corporation’s Steve Cardi Jr.
The bridge will be a network arch in which the arch and tie are connected by inclined hangers that join twice. Also known as a Neilson-Lohse bridge, it is popular in Japan and Europe for its appealing aesthetics. The bridge in Providence will be the first skewed network arch bridge. What makes it unusual is that there will be three arches instead of the normal two because it is so wide.
The network arch (or feature) part of the bridge will measure 400 ft. (121.2 m) while the overall bridge will be 1,235 ft. (374.2 m) long. Including the arches, it will be 167 ft. (50.6 m) wide and will stand 80 ft. (24.2 m) high. There will be a clearance of 34 ft. (10.3 m) over the water. The feature span also will have 47,000 bolts in the structure, as well as one mi. (1.6 km) of cable.
It would seem to be easier to build the bridge right on the site, but according to Cardi, “it’s more economic, we hope” to build it at a different location and then move it. By doing it this way, Cardi hoped to avoid having to drive piles.
The bridge will cross the Providence River at the site of the hurricane barrier in the city, approximately 2,000 ft. (606 m) to the south of the current span. The committee overseeing the bridge’s design chose the Neilson-Lohse design over a cable-stayed bridge, because it was so much more aesthetically pleasing.
“We decided on a bridge in harmony with the existing character,” Farhoumand said.
Two lanes of eastbound traffic should be open by June 2007, while westbound lanes won’t open until the end of that year, said Lambri Zerva, design project manager of RIDOT.
As part of the same contract, Cardi also is building concrete bridges over South Main Street and India Street just east of the river.
Such an immense project requires scores of contractors and subcontractors. The ones working specifically with Cardi Corporation on the signature bridge include: C&J Forms, concrete, North Kingstown, RI; Reito, caissons and piers, San Leandro, CA; National Eastern Fabricators, steel fabricators, Plainville, CT; and Northeast Steel Corp., erectors, North Kingstown, RI. Mammoet Corp. of Cambridge, Ontario, will be in charge of the actual barge transport.
In the same vein, many different large pieces of equipment are being used, such as Manitowoc 999 cranes, 230-ton (208.6 t) Link-Belt cranes, 120-ton (108.8 t) Grove cranes, as well as 365 Caterpillar backhoes.
A price of $65 million has been given the entire bridge, with $32 million of that designated for the feature span. The cost of the entire I-195 relocation project (also known as “Iway”) is $550 million. CEG