Fifty Percent of the Concrete is Poured
The last of the concrete for the columns–the top section of Pier 4 southbound–was poured yesterday, so all 12 of the columns at Piers 2, 3 and 4 have now reached their full height of 70 feet. Crews also finished pouring the last of the concrete at Abutment 5 this week. With that pour, the project has placed about 25,000 yards of the 48,700 cubic yards required for the new bridge.
From the time concrete was poured into the first of the forms on Jan. 31, construction of those 12 columns and two abutments took just more than six weeks. To accomplish this, the project had to have enough forms on hand to use in several locations simultaneously. Ordinarily, one set of forms would be reused several times, stretching the work out over a much longer period of time. Great care has been taken to protect the concrete from the cold weather, but as temperatures warm up this spring, the insulation around the columns will be removed.
Construction Update
Work on the segments for the main span over the Mississippi is also progressing well. Crews will continue to build casting beds and pre-cast segment forms in the casting yard. These segments will be used to form the main span of the bridge. Currently, 14 of the 120 necessary segments have been cast. This photo shows a close-up of the white post-tensioning ducts embedded in the pre-cast segments. High-strength steel tendons will run through these ducts, across the top and bottom of each of the segments, and a hydraulic jack will be used to pull on the tendons and compress the concrete segments tightly together.
Other work scheduled for the upcoming week:
The “falsework” (temporary support structures) on the south side of the project will continue to be built out to the columns at Pier 2. Carpenters and iron workers continue work on the approach span forms which includes placing rebar in these forms. Flatiron officials anticipate pouring concrete for the first section of the south spans later this month.
Crews continue building forms for the retaining walls between Abutment 5 and the Second Street bridge.
The walls for the Second Street bridge are under construction.
Potential Noise Impacts
Crews have been using this concrete crusher, set up on I-35W just north of Fourth Street SE, to break up big chunks of the old roadway so that they can be recycled and used for the base of the new roadway. A loud, steady hum and back-up alarms are noticeable while the crusher is in use. Out of consideration for people living and working in the area, the crushing will only take place between 7 a.m. and 6 p.m. Monday through Saturday. The crushing should be complete–or nearly so–by the end of the week.
The sound of hammering steel will also be noticeable as work continues on the “falsework” that will support the forms for the spans of the bridge on both sides of the river.
Potential Light Impacts
Crews are working night shifts seven days a week on both sides of the river as well as in the casting yard. Lights may be noticeable between 5:30 p.m. and 4 a.m.
Potential Traffic Impacts
Street Closures Needed at 14th Avenue South and First Street South –
Beginning in late March and continuing through early June, 14th Avenue South and First Street South (near the Seven Corners Apartments and Riverview Tower Condos) will be closed to allow utility relocation and widening of I-35W northbound. Access to the Seven Corners parking ramp will be maintained during this time period. On-street parking on Second Street South and 14th Avenue will be restricted to allow two-way traffic along Second Street South from 19th Avenue to the closure.
10th Avenue Bike Lane Closed – Due to the increasingly large crowds showing up at recent Sidewalk Superintendent Talks–more than 100 people have attended on two of the last three Saturdays–the bike lane on the west side of the 10th Avenue Bridge will be closed until further notice from 11 a.m. until noon on Saturdays. This is to ensure the safety of everyone using the bridge. The City of Minneapolis approved of posting signs at each end of the bridge last week that indicate the restriction. Bikes and pedestrians are urged to use the lane on the east side of the bridge between 11 a.m. and noon.
Truck Traffic - Trucks will be departing from the construction site regularly during daylight hours, going east on Second Street SE, north on 11th Avenue SE, and then east on University Avenue. Trucks will also be periodically hauling material into the site by traveling west on Washington Avenue, north on 11th Avenue South, east on Second Street South and north on 13th Avenue.
Planning Your Route to Downtown Minneapolis – The Minnesota Twins home opener is scheduled for Monday, March 31, and to ease traffic congestion, the Twins would like to strongly urge fans to utilize public transportation when possible. If you are planning to drive to the game, or anywhere else downtown, you can use the links below to plan your route:
City of Minneapolis Route Planner
www.ci.minneapolis.mn.us/traffic/routeplannerintro.asp
Minnesota Department of Transportation
http://projects.dot.state.mn.us/35wbridge/traffic.html