Work is well underway on the main pylon foundation for the Christopher S. Bond Bridge on the kcICON project in Kansas City. By Labor Day, 4 of the 8 shafts (with 10.5-foot diameter rock sockets) will be completed. Construction of the shafts is progressing smoothly. The Pylon shafts may be completed as early as the end of September. Work on the land shafts will start sometime after Labor Day.

The photos in the slide show below were provided courtesy of the Missouri Department of Transportation (MoDOT).

Update: MoDOT has set up a webcam on the exisiting bridge looking down on the pylon construction. Check it out here.

Technorati : Bridge Foundations, Deep Foundations, Drilled Shafts, Foundation Construction, Foundations, Geotechnical Engineering

Audubon Bridge Constructors (ABC) is making progress on the new John Jame Audubon Bridge near New Roads and St. Francisville, Louisiana. Steve has been spending quite a bit of time there looking at shaft excavations ,test shaft installations, and test pile installations. Paul made a trip in July and I made one earlier this month to give Steve a break. It is really amazing to be part of such a large bridge project. The amount of work required to build the foundations is incredible. I have posted a couple of slide shows below from the visits Paul and I made. Links to the slide shows and albums are on the project page.

Shafts W21 and W 5 – July 2008

Shaft W12 and West High Approach Test Shaft – August 2008

Technorati : Bridge Foundations, Deep Foundations, Drilled Shafts, Foundation Construction, Foundations, Geotechnical Engineering, Post-grouted Drilled Shafts, Test Shaft, Tip-grout

I have been slow in posting on the progress of our part in the kcICON project (see here for background and here for latest project images by MoDOT). The exploratory drilling went very well with a short pause due to ice in the river in late January. The crews from Terracon did an outstanding job getting the borings completed, overcoming the occasional problems with drilling tools deciding they did not want to come out of the hole.

Design work by Parsons on the main bridge proceeded (and is still ongoing) through the rest of winter and into the spring. In late April, PCC installed the test shaft in the middle of the pylon foundation with a 6-foot diameter rock socket 20 feet long. The shaft was tested using a group of 3 O-cells placed near the bottom of the shaft. The test yielded excellent results in both side shear and end bearing in the shale socket. Look for us to include the results in a future technical paper or journal article.

Design is continuing with the pylon shafts anticipated to be started in early July. The abutments and approach piers are schedule to be started later this summer or early fall.

The slide show embedded below has some photos of the exploratory drilling and the test shaft installation. Enjoy!

Technorati : Bridge Foundations, Deep Foundations, Drilled Shafts, Foundation Construction, Foundations, Geotechnical Engineering, Load Test, Test Shaft

DBA is part of a research project involving laterally loaded drilled shafts and MSE walls with the Kansas Department of Transportation (KDOT) and the University of Kansas. The ultimate goal of the study is to develop rational design procedures for situations where drilled shafts are constructed near or adjacent to MSE walls. From the study proposal:

Drilled shafts used to support sound walls and other structures are often constructed near the facing of mechanically stabilized earth walls (MSE walls) due to right-of-way constraints or other limitations. Suppliers and designers have expressed concern that lateral loads from the shafts may be transferred to the wall facing, causing excessive deformation. Procedures currently available to design MSE walls to resist internal lateral loads are very conservative isolating the shafts from the backfill or the using extremely large shafts to minimize deflection have been adopted. These designs are very expensive and in some cases lead to other problems. Results from this research project are expected to lead to much more cost effective designs on subsequent KDOT projects. We expect that the results will lead to improved national design standards for this type of construction as well.

Seven test shafts and 6 reaction shafts were constructed at the tests site, with some of the shafts socketed into the underlying limestone and shale bedrock. All of the test shafts were located within the reinforced backfill zone of the wall, varying the distance between the shaft and the wall face. Single shafts and shaft groups were loaded laterally. The wall face, reinforcing geogrid materials, and backfill were instrumented to measure loads, strains, and movements. The shafts were built with inclinometer casings to allow measurement of shaft deflections using an inclinometer during the tests. Many of the materials and construction work for the wall and shafts were made as in-kind donations by various companies, including Tensar who supplied the geogrid. KDOT Maintenance personnel perfomed most of the construction work and provided support for the load tests.

The tests took place between November 5th and 16th. I was on site the 12th through 16th to observe the tests, provide oversight, and assist Chris Kohlhof of AFT with running the tests. You can see a photo album or slideshow of some photos from my time at the site by clicking below.

KDOT Wall

Dr. Bob Parsons, P.E. of the University of Kansas Department of Civil, Environmental and Architectual Engineering will concentrate on analyzing the data concenring the wall and the backfill. DBA will analyze the lateral load tests data to derive p-y relationships for shaft design and will prepare a report on the load tests that includes design recommendations.

Technorati : Deep Foundations, Drilled Piles, Drilled Shafts, Engineering Research, Foundation Construction, Foundations, Geotechnical Engineering, Load Test, Test Shaft