Steele Street Bridge
HOME/INTRO • HISTORY • DEMOLITION • RECONSTRUCTION • EPILOGUE

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Once the Steele Street Bridge had been demolished, the reconstruction effort would begin. The general process to rebuild the bridge proceeded in these steps:

  1. Demolish the old bridge.
  2. Drill caissons for the two abutments at each end and the pier in the median. Lower rebar cages into the shafts and fill with concrete.
  3. At each end of the bridge form and pour an abutment on top of the caissons. In the median form and pour a pier cap on the top of the caissons.
  4. Lower girders into place spanning the gap between the pier and each abutment.
  5. Place the rebar system for the deck. Pour the deck.
  6. Form and pour the curbs and sidewalks. Place railing, fencing and lighting.
  7. Rebuild the approaches as necessary.
  8. Perform final cleanup work. Open the bridge to the public.

This photo shows the tops of caissons that have been drilled and poured at the north end for the north abutment (13Apr02).

Once the caissons at each end of the bridge had been drilled and poured, the abutments could be built on top of them. The abutments are basically shelves on which the ends of the girders sit. Wood formwork is put in place to form the abutment and the rebar placed, and then concrete is poured into the formwork to create the abutment.

A photo of the new south abutment (11May02). The pads are the things on which the "bulb-T" girders will sit. The large hole through the abutment is for a water line which will hang below the deck.

While the two abutments support the girders at each end of the bridge, a pier supports them in the median of I-25. The pier was constructed by first drilling three caissons, then forming a pier cap on top of it. A pier cap is basically a large horizontal concrete beam on which the girders sit.

A view from the temporary pedestrian bridge of the center pier (27Apr02). The wood is formwork on top of the caissons to form the pier cap.

Another view of the center pier, a couple of weeks later (11May02). This also provides a good overall view of the bridge work area as it appeared in early May.

Once both abutments and the center pier were complete, the next major milestone could be accomplished: Setting the girders. The girders for the Steele Street Bridge are standard concrete "bulb-T" girders, precast and prestressed in a factory and then trucked to the site. There, they are lowered into place by a crane during an overnight total closure of I-25. This was done May 14.

A view of the bridge the weekend after girder setting (19May02).

Once the girders were in place, the next order of business was to create the deck on which the vehicles drive. The deck is a cast-in-place concrete slab on top of the girders. Before the deck can be poured, however, an intricate rebar system has to be laid.

The two photos below are of workers putting in the rebar system for the deck (15Jun02). The steel rebar, normally dark, is green because it is epoxy coated to keep it from rusting.

After all of the rebar for the deck had been laid, a deck pour would be done. The deck pour was a massive one-night operation where concrete was trucked in constantly so that the concrete for the entire deck of the bridge was poured. The deck pour was done June 19.

This photo looks north along the bridge a couple of weeks after the deck pour (6Jul02). The plywood lining the sides of the bridge is formwork that will be used for the rails. The bolts sticking up in the sidewalk are for light poles.

A view of the north end of the bridge (6Jul02). The end of the concrete is where the deck ends and the approach slab will begin. The PVC pipe sticking out underneath the sidewalk is for electrical lines and other such utilities.

In July and early August, work concentrated on the final work to get the bridge ready for opening. This included forming and pouring the concrete approach slabs, reconstructing the asphalt approaches and curb on the street which equipment had torn up, putting in railing, fencing, and lighting, and forming and pouring six "monuments" that add an aesthetic element to the bridge.

Here a worker trowels on a coating on the railing at the southeast corner of the bridge (3Aug02).

The bridge was complete enough to open it to pedestrian traffic on August 6. The next day the temporary pedestrian bridge was removed. The Steele Street Bridge opened to vehicle traffic the morning of Monday, August 19, 2002, 224 days after it had closed.

Go to the Epilogue for photos the completed bridge, as well as a time lapse movie showing the work progressing.

Steele Street Bridge:
HOME/INTRO • HISTORY • DEMOLITION • RECONSTRUCTION • EPILOGUE

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Page created 19 April 2002
Last updated 21 September 2002

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