Jordan Bridge construction incident setback for builder/investors in South Norfolk VA UNDER REVISION
2012-06-24: The collapse of components of an approach span under construction at the Elizabeth River in South Norfolk looks from photographs to be quite serious. The companies who are partnered with a private investor group have made no comment yet, but local TV footage shows bridge segments askew every which way above and a major debris field of damaged and broken concrete below. (ADDITION: Linda Figg president of Figg Engineering says Monday morning our report has "sensationalized" the incident, that there was "no "collapse" a term we first used here. We've now been promised details of what happened, so expect revisions/elaborations - editor Jun 25 11:25)
Fortunately no one was seriously hurt in the accident but it seems likely to cause delays in the opening of the bridge which had previously been set for July 14.
A construction camera showing the scene at 3:55pm June 21 shortly before the collapse seems to show the two projecting construction trusses (painted yellow) unattached to the end pier - just floating out there. Which seems mighty strange. There is no sign of the temporary beam normally attached to the top of the pier to support the far end of each truss.
Floating trusses just before collapse look strange to us
Construction crews appear to have been relying on the cantilever strength of the truss projecting beyond the completed span. (We're making an unprofessional observation, just looking at the time stamped picture, and we'll revise it if we can get more authoritative information about what happened - editor.)
This is segmental box girder construction in which approximate 150ft, 46m spans are pieced together out of precast units that provide the full deck width of some 52ft, 15.8m and the full structural box depth in the center of about 12ft, 3.7m high.
But about 22 or 23 such segments of this kind have to be stitched together to build the 150ft, 46m span between permanent piers because each unit is only 6.75ft, 2m long. Until the twenty-plus segments for a span can all be erected, and be tied together with heavy steel cables that are tensioned and grouted, they have their weight supported by two steel trusses, one under each projecting deck portion, the structural box element sitting down between the twin temporary trusses. The trusses in turn are usually supported by each pier by a beam temporarily attached to it.
In any case the trusses seem to have moved causing the 155,000 pound, 70 ton segments - not yet tied together - to skew, slide and in some cases drop. This was an approach span not far from the beginning of the bridge so it was not high - just providing clearance for a railroad line.
Tampa collapse in 2005
There was a construction accident using similar segmental box girders for the Tampa area toll authority when building the reversible elevated lanes of the Selmon Crosstown Expressway in 2005. That delayed completion about a year and was the subject of litigation that was settled with the Tampa toller getting $74m compenstion.
The problem in Tampa was described as "a geotechnical issue" - a problem of poorly engineered and specified built pilings. URS engineers were responsible for the errors.
Figg Engineering, responsible for the superstructure was exonerated. (REVISION)
Building for themselves
Here in Norfolk VA the companies are building essentially for themselves under a longterm concession. The bridge replaces a 1926 steel truss lift bridge that was first in private and later City of Chesapeake ownership but closed November 2008 when found structurally unsafe.
The composition of the investment group changed. Initially it was reported to be Figg Engineering and Britton Hill Partners (BHP) whose interest in the project was transferred to American Infrastructure MLP Funds United Bridge Partners (UBP.) And Lane Construction came in.
The same group Figg, Lane and UBP recently was accepted by the City of East Chicago Indiana to build a private toll bridge in Cline Avenue - another case of an old lift bridge deteriorating to the point it was unsafe and had to be closed.
BACKGROUND: The Jordan Bridge connects South Norfolk with southern Portsmouth over an estuarial section of the Elizabeth River that is 2,000ft, 600m wide in an industrial and port area. Norfolk Naval Ship Yards employing over 10,000 people are located immediately on the west side of the bridge.
Location is less than 2 miles, 3km south of the I-264 Downtown Tunnel and 2 miles north of the US13/460 crossing. The I-64 Beltway crossing of the Elizabeth River is about 4.7 miles,7km to the south.
The river forms part of the Intra Coastal Waterway and the old bridge was typically raised 20 to 30 times per day (10,000 lifts/year) for about 22,000 vessel passages a year (an average 60/day) seriously limiting its availability to car traffic. The allowed weight on the bridge was progressively reduced and for the last 12 years was posted at 2.7t (6000pds, 3 short tons).
So worried was the old bridge owner City of Chesapeake about the bridge collapsing from an overweight vehicle after receiving the last engineering report that from the early summer they posted an officer at each end of the bridge to turn back overweight vehicles.
Not strictly a concession - an agreement to build & toll
Under their agreement with the City the investors have taken full responsibility for financing, building and operating the new bridge, including purchase of some extra right of way needed and removed the old abandoned lift bridge. As joint owners and operators of the new bridge they will have full right to the tolls. They committed to expanding the capacity of the bridge in line with demand.
It is being built initially 2 lanes expecting less than 10,000 vehicles a day but could be doubled with a parallel span if traffic warranted.
The bridge spans an estuarial section of the Elizabeth River with a width of 600m (2000ft). The old bridge was a mere 15ft, 4m to 5m above the water. The new private bridge has a center span of 365ft, 111m and a overhead clearance of 145ft, 44.2m.
With approaches the new Jordan Bridge is 5375ft, 1640m long overall to provide 145ft, 44.2m of overhead clearance with approach grades of no more than 5%. There are 35 spans, 32 of them 150ft, 46m. The central span is 375ft, 114m and spans on either side of that are 200ft, 60m.
The deck provides for two travel lanes of 12ft, 3.6m, two shoulders of 8ft, 2.4m and a pedestrian/bicycle lane.
Project cost was put at around $100m - before the June 21 collapse.
The bridge company has announced its tolls which are $2 for a car with an E-ZPass account. They have an interesting three tier set of tolls. Pay-by-plate is $1 extra per transaction if the license plate is 'Registered' meaning the motorist goes to the bridge website and provides license plate number, name and address for a monthly bill. An Unregistered vehicle incurs a $2 surcharge on the base E-ZPass rate as compared to the $1 surcharge for Registered.
In 'commuting hours' (5:30-9am, 2:30 to 7pm) the trucks, 3-axles and more pay a $2 surcharge for the toll, whatever the mode of payment. The theory is the trucks will slow the traffic because of the steep grade so it will help if they can be encouraged to travel outside commuting hours for the car drivers.
The bridge will compete as a toll facility with the Downtown Tunnel I-264 just north but with untolled crossings to the south - an interesting competitive dynamic.
see bridge website:
2008-12-29 Investors propose to build replacement bridge:
2009-01-29 Chesapeake City accepts Figg proposal:
2009-02-24 Private bridge gets Virginia state legislative OK:
Same group Figg and MLP Funds get East Chicago concession:
Our account of the Tampa Selmon incident: