Awarded to Metro Wastewater Treatment Plant - Pile Driving ...

Figure 5 – Response Spectra
Figure 6 – P-Y Curve
Figure 7 – “Spin Fin” Pipe Pile
Tension and Compression Tests.
PILE DRIVING
CONSULTANTS
Dynamic Pile Testing, PDA
Static Pile Testing
Pile Instrumentation
Pile Driving Consulting
Cross-Hole Sonic Logging
PO Box 58621
Salt Lake City,
Utah 84158
Phone:
801-566-9581
801-330-0527
At this point, maximum pile stress was
13.6 ksi due to lateral seismic forces only.
By designing the “spin fin” for
some pile axial deformation to occur,
an effective axial spring constant can be
assigned to each pile. (See Figure 6.)
For a k = 650 kips/inch, a new
structure period (T) of 1.26 seconds was
computed, giving a maximum pile stress
of 7.8 ksi, which is significantly less than
the rigid case.
This simple example helps to illustrate
the interesting possibilities of the
“spin fin” pile system and appropriate
analysis.
Another 24-inch diameter “spin
fin” pipe pile load test in both tension
and compression also helps show
spring characteristics of the system.
(See Figure 7.)
Summary
To effectively establish realistic
repetitious tension and compression
“spin fin” pipe pile performance, more
testing is required. However, positive
implications of the use of the controlled
features of “spin fin” piles offer a system
with the potential to resist large and
unusual repetitive loads. ▼
24 • Spring 2004