Optimizing the Use of the Thermal Integrity System for Evaluating Auger-Cast Piles

Auger-cast piles (sometimes called auger-cast-in-place, or ACIP, piles) are a subset of the larger category of deep foundation elements known as bored piles. Although similar to drilled shafts at first glance, ACIP piles differ in the construction processes and design capacity. Therein, ACIP piles require no slurry or casing to hold open the excavation; rather, a continuous flight auger is used which maintains the stability and volume of the excavation via the soil that fills the auger flights. In this regard, no means of inspecting the dimensions of the borehole is provided and the as-built pile dimensions can only be inferred from grout pumping logs. The resultant shape of the foundation element is further dependent on the rate of auger extraction relative to the grout pumping rate. With this in mind, there is concern of the as-built shape and integrity. As such, use of ACIP by the Florida Department of Transportation (FDOT) has been limited to foundations for sound walls. The thermal integrity test has proven to be an effective method to evaluate the integrity of newly constructed drilled shafts (i.e. identifying anomalies, rebar cage alignment, concrete cover, etc.). However, very few auger-cast piles have been tested with this method as standard integrity access tubes are not typically installed. If an improved quality assessment tool is developed to ascertain the final, as-built configuration (size, depth, diameter, concrete cover, etc.) of auger-cast piles, their use in other applications can be reevaluated. The results of this study showed the limitations of various instrumentation schemes and introduced alternate analysis methods specific to ACIP piles.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 180p

Subject/Index Terms

Filing Info

  • Accession Number: 01608564
  • Record Type: Publication
  • Contract Numbers: BDV25-977-09
  • Files: TRIS, ATRI, STATEDOT
  • Created Date: Aug 8 2016 10:24AM