The PDA is the most widely employed system for Dynamic Load Testing in the
world. It can assess the capacity of multiple drilled shafts, cast-in-place, continuous flight auger or
bored or driven piles in a single day.
PDA tests, or High Strain Dynamic Tests, simply require a drop weight (see examples) to
impact the shaft, and that the top of the foundation be cushioned by a few thin plywood sheets.
The light and battery operated PAX is available with 4 or 8 channels of data acquisition;
8 channels are important for testing cast-in-place piles and drilled shafts. The PAX gives the engineer the
option of being present for the test or avoiding travel to the job (SiteLink® PDA Testing).
When the engineer is present for the test the PAX runs in local mode and displays all test data and results on its LCD screen.
When only the PAX is on location a field crew sets up the test and the PAX transmits test
data via a broad band internet connection, while an engineer located elsewhere follows the test in real
time.
The PDA calculates results from velocity and force signals obtained by sensors
(accelerometers and strain transducers) attached to the foundation. These sensors may be Smart (transmit data using Wireless Transmitters)
or Traditional (transmit data via cable).
Pile Driving Analyzers include the PDA Software Suite, CAPWAP® and GRLWEAP. CAPWAP analysis of PDA data is essential for a Dynamic Load Test. It provides the soil resistance distribution along the foundation and simulates a static load test. Extensive correlations between CAPWAP simulated and actual static load tests have proven the reliability of this method of determining pile capacity.
The Pile Driving Analyzer conforms to
ASTM D4945 and many other codes and specifications. The PDA software suite, consisting of PDA-W with ICAP®, PDIPLOT
and PDICURVES, outputs reports that satisfy ASTM 4945 requirements.
Pile Dynamics recommends that all those who perform dynamic tests using the PDA take the Dynamic Measurement and Analysis Proficiency Test
offered by PDI and PDCA, and/or the High Strain Dynamic Pile Testing Examination offered by Foundation QA (FQA).
Read about need for quality testing.
The Pile Driving Analyzer may also be used to determine the energy transferred to SPT rods.
The PAX is patented under the Remote Pile Driving Analyzer US Patent No. US 6301551.
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