Ayres Knowledge Center Scour Evaluation: Bridges with Unknown Foundations | Page 28

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EXECUTIVE SUMMARY
Olson Engineering, Inc. was contracted by Ayres Associates to determine unknown, actual as-
built foundation depth of Main Street Bridge over Halifax River (FDOT 794004) Daytona
Beach, Florida. This report includes the results for PS tests on Bridge 794004, Pier 17, SW
Corner Pile. Table I summarizes the pile tip depth results for the foundation element tested on
this bridge. The pile tip depth is measured from the top of the PVC casing, and the top of the
casing was measured to a reference point on the bridge pier. It is estimated that the pile tip depth
reported herein is accurate to within approximately + 1 to 2 ft (from 1 to 2 times the PS
hydrophone receiver test depth interval of 1 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.
Table I - Pile Tip Depth Results from Parallel Seismic Tests
Bridge/Pier/Pile
794004/ Pier 17 SW Corner
Top of PVC
Casing Elev. (ft)
+1.8
Top Pile Cap
Elev. (ft)
-8.2
Mud Line
Elev. (ft)
-12.2
Pile Tip
Depth (ft)
104
Concrete Pile Tip
Depth Elev. (ft)
-102.2. + 1.0
The vertical axes in PS test results (see Appendix A) represent the depth below the PVC
casing top for each PS hydrophone receiver waveform in response to hammer impacts plotted at
1 ft depth intervals starting from the casing bottom depths. The horizontal axis represents
acoustic wave travel time in milliseconds (ms). The depths of the pilings are indicated by slower
velocities for wave arrivals below the apparent pile tips and corresponding weaker signals in the
PS results plots as discussed herein.
Olson Job No. 4174A-3
Supplementary Report
Bridge 794004
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