Ayres Knowledge Center Scour Evaluation: Bridges with Unknown Foundations | Page 31

The PS test data was collected with an Olson Instruments portable Freedom Data PC (see
www.olsoninstruments.com). The PVC-cased borehole on Bridge 794004 was located roughly 4
feet from the South Face of the West Bascule Pier (Pier 17). The Parallel Seismic tests were
performed at hydrophone receiver depth intervals of nominally 1 ft for the entire water-filled
length of the boreholes. For the testing, the hydrophone started at a depth of 115 ft. The PS
results plot for the tested pile is presented in Appendix A along with Summary Table A-1 of the
PS results and which are discussed below.
For Bridge 794004 Pier 17 a concrete pile tip depth of 104.0 ft below the top of the PVC
tube (90 ft embedment depth below mud line) was found for this foundation. The data was
collected with 3-lb hammer impacts to a the concrete lip at 4 ft above the mud line, with results
as shown in Figure A-1 in Appendix A. Review of this figure shows a concrete pile velocity of
about 11,963 ft/s followed by a slower velocity of about 5,900 ft/s which is indicative of
saturated soils beyond the predicted pile tip embedded depth of 90 ft. Review of the Nodarse
boring log in Appendix B indicates that the pile is embedded in a light tan weathered limestone
with standard penetration test blowcounts indicative of very stiff to hard materials.
Olson Job No. 4174A-3
Supplementary Report
FDOT Bridge 794004
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