According to Shawn Clark, Northern Construction project manager, tree clearing began on Nov. 6 of both the east and west staging areas, accompanied by the continuance of utility relocations that have been ongoing for several months.
Clark said that excavation work for both staging areas began on site on Nov. 18. Approximately 10,000 cu. yds. (7,645.5 cu m) of excavation is required to bring the two staging areas to a flat grade so that the new bridges can be constructed in each of these areas on temporary bridge abutment supports.
According to ConnDOT, the bridges were constructed in 1963 with some rehabilitation work performed in 1995. Deterioration is typical for these 50-year-old bridges, but its foundation is solid. The spans have weakened, but the abutments are in good condition.
Some 83,800 vehicles per day on average cross the highways, based on a study completed in 2008. This includes both eastbound and westbound totals. There are three lanes of traffic in each direction with breakdown lanes. The new bridges, already fabricated, are 53 ft. (16.2 m) wide from curb to curb.
Clark and ConnDOT confirm that upon completion of the prefabrication of the new superstructures, Interstate 84 eastbound and westbound at Exit 30 and Marion Avenue will be closed for one 56-hour weekend next summer.
The prefabricated superstructures will be moved from the staging areas using self-propelled modular transporters (SPMTs) to replace the existing superstructures. The existing bridges will be removed and new structures will then be set into place.
Existing structures built in 1963, are single span structures that consist of a concrete deck slab on pre-stressed girders. Clark said the new structures will be of a similar design however, the vertical clearance on Marion Avenue under the bridges will be increased based on evidence of impact damage on the fascia girders.
The existing vertical clearances are 21 ft. 8 in. (6.6 m) at the eastbound structure and 15 ft. 10 in. (4.8 m) at the westbound structure. The proposed vertical clearances over Marion Avenue are 22 ft. 2 in. (6.8 m) at the eastbound structure and 16 ft. 4 in. (5 m) at the westbound structure.
The bridges weigh approximately 1,000 tons (907 t) each.
“Temporary staging areas and access roads from the eastbound and westbound staging onto Marion Avenue will be required to transport the bridges from the staging areas to their permanent locations,” said Clark. “These staging areas will be loamed and seeded after the work is completed. The bridges will be constructed in staging areas and transported via the use of SPMT units.
“After demo is completed, the new bridges will be placed on the existing abutments that require minor modifications. The process of moving the bridge is that the SPMT units will move under the new bridges constructed on temporary abutment supports,” said Clark. “They will jack up the bridge off of the supports and travel up Marion Avenue and lower the bridges onto the abutments. The existing abutments are being utilized with minor modifications as they are in very good condition.”
Done in Eight Months
The completion date of the project is July 2014.
“The bridges will be closed on Friday evening of whatever weekend we choose based on weather, among other things, and the bridges will be re-opened by Monday morning fully to traffic,” said Clark. “The specifications require that I-84 only be closed for a weekend, which is why the SPMTs are being utilized for this accelerated construction.”
According to Northern, this project requires the approximate quantities of materials as follows:
• 3,000 tons (2,721.6 t) of process gravel for staging areas
• 2,000 tons (1,814.4 t) of asphalt for paving Interstate 84
• 45,000 sq. ft. (4,180.6 sq m) of milling/cold planing of existing asphalt for new overlay
• 1,300 cu. yds. (993.9 cu m) of concrete for beams, approach slabs and abutments
• 40 bearing pads for beams to rest on
• 45 tons (40.8 t) of rebar cast into concrete
• 13,000 sq. ft. (1,207.7 sq m) of membrane waterproofing for bridge decks
Bridges will be constructed in staging areas in advance of the closure of the bridges carrying Rte. 84 over Marion Avenue.
“When Marion Avenue is closed, rapid replacement can commence with prefabricated bridges. This is as opposed to constructing the bridges in phases and open to traffic which would take several years,” said Clark.
“We have all been attending seminars for Federal Highway Initiatives. There are a lot of innovative practices being looked at,” said Terri Thompson, transportation supervising engineer of the ConnDOT's office of construction in Newington, Conn. “This type of project, using accelerated bridge methods, allows us to look at more and more ways to use our abilities to get in and get out quickly.
“Northern will be using different techniques,” added Thompson. “Sliding one bridge out, lifting a new bridge in and using a combination of these techniques. One bridge will be under demolition and one will be lifted, and another bridge will be cut and taken down. We will be going in two directions at the same time.”
The designer of the new bridges is Stantec, 2321 Whitney Ave., Hamden, Conn.
“We will be constructing the new bridges during normal working hours, approximately 7 a.m. to 4 p.m. Monday through Friday. During the weekend of the accelerated bridge move, we will have two crews (one on each bridge), each working 12-hour shifts (one during day and one at night), and the same will go for the other bridge since there are two bridges,” said Clark.
On this project, time is literally money.
“Since this is a weekend closure, ConnDOT has specified the following: There is a $250,000 incentive if we open the bridges Sunday before 10 a.m. Then, starting at 5 a.m. on Monday morning, there is an hourly incremental disincentive up to $1 million, if the bridges are not open by 5 a.m. in both directions.”
Marino/Barnhart out of Newington, Conn., is moving the prefabricated bridges into place.
Northern Construction LLC, a well-regarded company, which has performed numerous DOT highway and bridge projects throughout New England, is based in Palmer, Mass.
Sean Hoey, superintendent will run the fieldwork for Northern in addition to Clark. Shawn Mangan, ConnDOT resident engineer will supervise the work for ConnDOT and Joe Calafiore, area engineer of ConnDOT will supervise Mangan.
Thompson said there is tremendous interest among Connecticut commuters on this project.
“Northern is a great partner. It's a large effort by a smaller company and there is much interest in that.
“Since we are closing Interstate 84 for a weekend, some 56 hours in June 2014, there is a lot of interest in what they are doing and how they are doing it,” said Thompson. “We plan to hold a public information meeting on this. They always prove to be helpful. People in the areas under construction like the meetings to show them how we are lifting these bridges and doing this project.”
For more information on Northern visit www.northernconstruction.com.
For more information on accelerated bridge construction (ABC) visit http://www.fhwa.dot.gov/bridge/abc/.
(This story also can be found on Construction Equipment Guide's Web site at www.constructionequipmentguide.com.) CEG
Clark provided the names of an outstanding team of sub-contractors from six states — Texas, Pennsylvania, New York, Connecticut, Massachusetts and Rhode Island:
• Rebar — Brooklyn Rebar, Brooklyn, N.Y.
• Paving — Conn. Paving LLC, Rocky Hill, Conn.
• Surveying — DiCara Land Surveying, Winstead, Conn.
• Bearing Pads — Dynamic Rubber, Athens, Texas
• Guardrail and Fence — Eagle Fence, Plainville, Conn.
• Ready-Mix Concrete — F&F Concrete, Plantsville, Conn.
• Structure Monitoring and Vibration — Geocomp Engineering, New York, N.Y.
• Geotechnical Engineering — GZA, Glastonbury, Conn.
• Electrical — KTM Electric, Orange, Conn.
• Rebar Installation — Lintec LLC, Andover, Conn.
• SPMT and Heavy Lift Bridge Move — Marino/Barnhart, Newington, Conn.
• Landscaping and Seeding — Medeiros Hydroseeding and Landscaping, Monson, Mass.
• Precast Bridge Beams and Approach Slabs — Northeast Pre-stressed Products, Cressona, Pa.
• Tree Clearing — Northern Tree Service, Palmer, Mass.
• Waterproofing and Bridge Joints — Santoro Inc., Newington, Conn.
• Miscellaneous steel fabrication — Southington Metals, Southington, Conn.
• Engineering Procedures (Erection, Demo and miscellaneous structural) — Steere Engineering, Warwick, R.I.
• Demolition of existing bridges — The Demolition Corporation, East Boston, Mass.