Work Underway on Benton Street Bridge

December 10, 2019

The progress on the Benton Bridge has been slowed by cold weather the last few months. The Contractor has completed the concrete patch and repair for all Piers except Pier 12. The remaining tasks include Installing the pier conduit, junction boxes, pull pier wire, and pulling rectifier wire on all the piers. There is also rectifier conduit to install, girder bays to paint, carbon fiber wrap to install, and anodes to finish installing on a few of the piers. The testing for the carbon fiber wrapping need to be completed on Pier 12, 11 and a retest on Pier 10. Dollies have been installed and the pull off tests are anticipated to happen in the next few weeks as the epoxy takes longer to cure in the cold weather. The crews are also working to finish the repair on the abutments. The Electrician will pull the mainline conduit and rectifier wires next week.

October 29, 2019

The Contractor has completed the carbon fiber wrapping on the bullnoses for Piers 4-9. The Electrician has completed the main panel so power to the system is active. The company Integrated Corrosion came to test the anode system. The complete system was tested over a period of two days and was cleared as functioning as intended. The company also trained City Staff who will be testing the system annually. The crews will start focusing on the abutment work in the coming weeks.

September 20, 2019

The Contractor has been working on electrical conduit prep on piers 1-4. They have also recently poured pier 11 and are working on pouring pier 12 with new concrete. In order to protect the girders from rust epoxy paint is being applied to the girder where it crosses the piers. This procedure has only been completed on pier 7 so far but will be done on each pier. In the coming weeks the Contractor will drill the holes for the anodes on pier 11 and 12 as well as continue work on the electrical portion of the project.

August 23, 2019

The Contractor has completed pier 7 with exception to the carbon fiber wrapping on the caps and columns. They will finish the carbon fiber wrapping on pier 7 next week then move on to pier 11 and 12. The Electrician is working on installing conduit sleeving on piers 1-4 and will continue to move across the structure.

July 23, 2019

Last week the Contractor worked on the pier 8 column footing repair 4-6 feet underground during a 24 hour track shut down. The repair included building a new foundation with steel reinforcement. The carbon fiber wrap was installed, the pull test which measures the adhesion strength of the fiber to concrete will be done tomorrow. The shoring has been removed and the sidewalk poured near pier 10.

July 11, 2019

The Contractor has completed the patch and repair on pier 8 and has been working on the anode installation this week. Next week they will be installing carbon fiber wrap on pier 8 and making underground repairs. They have also been working on faulty concrete removal on pier 11 and 12. The patches will be poured next week on these two piers. They expect to begin working on pier 7 the end of July.

June 7, 2019

The Contractor has completed pier 9 including painting. They are currently working to finish up pier 10 but the patch and repair and carbon fiber wrapping have been completed. When train schedules allow, the Contractor is working on removing the faulty concrete on pier 8. The traffic control measures are in place reducing the traffic pattern to one lane in each direction and one pedestrian route. The crane is in place on top of the bridge to assist in lowering materials down as well as providing a route for evacuation if the tracks are blocked.

May 7, 2019

The Contractor has been working on Piers 9 and 10. Last week they were finishing up the carbon fiber wrapping on Pier 9 in preparation to move to Pier 7 and 8. Currently the schedule shows beginning Pier 7 and 8 mid May which will include implementing the traffic control plan. There will be one lane of travel in each direction while they are using a crane on top of the bridge to access the piers underneath.

November 8, 2018

The Contractor has wrapped up work for the winter as of today. The patch and repair, underground work, installation of electrodes/anodes, and carbon fiber wrap has been completed on the west side of the bridge. The Contractor has also completed the two rectifier pads on each side of the railroad tracks and the patch and repair, underground work on pier 10. Work is anticipated to start up again April 15, 2019 by finishing the patch and repair of pier 9. During the work in the spring there will be a period of time that traffic will be reduced to one lane in each direction while a crane is used to access pier 7 and 8 from the top of the bridge. We ask for your patience with the traffic controls as we work to complete this project.”

October 10, 2018

The contractor has begun testing the strength of the carbon fiber wrap. The first step is to use a hole saw to cut a 2” dia hold in the carbon fiber wrap. Then they bond a little metal piece to the carbon fiber wrap with epoxy. After it has dried for 24 hrs, they use a machine to fit over the metal piece and apply pressure to test how much the fiber can withstand before it lifts free. The requirement is to get at least 200 PSI. We are getting over 500 so far and the fiber is not failing, the grout is breaking instead. The carbon fiber is passing the tests with flying colors so far.

October 5, 2018

Mid-July through the beginning of September the contractor has been rehabilitating the west side of the bridge then moved to the east side mid-September. The shoring for pier 9 and 10 has been installed and the contractor has been working on concrete patch and repair on those piers. The cathodic protection installed so far has been tested and has passed. Next week the contractor will be working on the pier caps on 9 and 10 as well as testing the strength of the carbon fiber wrap. The work on this bridge will stop for the winter around the first of November. For the remainder of October they will be focused on finishing the rehabilitation process on piers 9 through 12.

July 19, 2018

The contractor has begun installing the carbon fiber wrap to the structure. The purpose of the carbon fiber wrap is to reinforce the tensile strength of the rebar. First they roll down epoxy primer (dark gray color), then a layer of epoxy filler (light gray colored, fills in pock marks in concrete to increase surface contact), then epoxy saturant (blue, this saturates the fiber wrap bonding it to the concrete), and finally they install the carbon fiber strips. Depending on the strength needed some areas have two layers of the carbon fiber wrap and some have 4 layers. There is an epoxy saturant coat between the carbon fiber wrap layers and on top of the last fiber wrap. These areas will be painted gray when the process is completed. The carbon fiber system has to cure for 3 days before they can take out the shoring and it will be 7 days before it is maximum strength.

July 13, 2018

The contractor is approximately half way through the patch and repair portion of the work on the structure. Crews have bored 2-inch diameter holes in the columns and caps and are placing rust-prevention anodes into the structure. The photos below show the process, first the holes are filled with grout and then the anode is pushed into the grouted hole. The anodes will be connected with wire to an electrode (shown with yellow cords) that is producing current (.85 and 1.2 volts DC). This will cause the anode to rust instead of the rebar in the structure. Once the project is complete, 518 anodes and 79 electrodes will be installed which will help extend the life of the bridge. The contractor is working on installing the anode system on piers 1-6 currently. Next week they will begin the carbon fiber wrap to further strengthen the columns and pier caps.

May 18, 2018

Removal of faulty concrete on pier 5 continues. Next week patches will be repaired on pier 5 and they will continue to form pier 3 to prep for pouring. The contractor will also work on cutting groves in the columns for the wires and drill holes for the anodes which are part of the cathodic protection.

April 12, 2018

Construction on the Benton Street Bridge Project continues on Pier 4, which is adjacent to the eastern edge of the railroad track. In order to protect the track, plywood catchers were installed to minimize the amount of falling debris. Additionally, three shoring columns were installed on the bridge concrete beam to ensure safety. A comprehensive survey was done by City staff of the railroad track to ensure that the track is properly restored at the end of the project.

April 6, 2018

Construction on the Benton Street Bridge Project continues on Pier 1 and 2. These steel columns will be used to shore up the bridge to strengthen it while unsound material is removed. Finally, the contractor installed a camera system so the construction team can monitor the construction process.

March 29, 2018

Construction on the Benton Street Bridge Project has started this week. The bridge has 12 piers; the work so far has been on pier 1 and 2 on the east side of the bridge. Accomplishments this week have been the erection of shoring, testing of the bridge concrete piers, and beginning of removing the unsuitable material.