ACIP Pile Installation, Installation Monitoring, Full-scale Load Testing, and Extraction Program-PDF

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The 2017 Deep Foundations Institute report documents a full-scale demonstration of augered cast-in-place (ACIP) pile installation, monitoring, testing, and extraction in Okahumpka, Florida. Seven test piles—18 and 24 inches in diameter and 40 or 60 feet deep—were installed, along with reaction piles. The program evaluated automated installation monitoring, thermal integrity profiling (TIP), compression, tension and lateral performance, embedded strain-gage measurements, and the as-built condition of an extracted pile.<br /><br />Automated monitoring equipment recorded installation depth, penetration rate, hydraulic pressure, and grout flow and volume. Flow-meter measurements and manually counted grout-pump strokes generally agreed. TIP measurements from thermal probes and wires were also broadly consistent. TIP could help assess pile shape and integrity, particularly when sensors were placed around the reinforcement cage; results based only on a center bar could miss its misalignment. The report recommends further research to refine TIP interpretation and its application to ACIP piles.<br /><br />Full-scale load tests demonstrated substantial axial and lateral resistance. The compression piles reached maximum loads of approximately 447 and 371 tons, while the extracted pile showed no evidence of necking or inclusions. Its average diameter was about 19.4 inches, exceeding the nominal 18 inches. After accounting for grout that overflowed during installation, measured grout volumes aligned well with both manual circumference measurements and TIP-based estimates.<br /><br />The project supports considering ACIP piles for bridge foundations and provides data to inform Florida DOT specifications. The authors also identify needs for further evaluation of bidirectional load cells and improved monitoring and quality-assurance methods.

Keywords

augered cast-in-place piles

ACIP piles

full-scale load testing

thermal integrity profiling

pile installation monitoring

Florida bridge foundations

embedded strain gauges

compression and tension performance

lateral load resistance

pile extraction analysis