Publication Abstract

DFI-PFSF Piled Foundations & Ground Improvement Technology for the Modern Building and Infrastructure Sector, (DFI and PFSF)

Case Study: Load Transfer Analysis on an Instrumented Augercast Pile Using EDC Strain Gauges and Geokon Rebar Strainmeters
Swamy Avasarala, President, Santosh Mummaneni, Project Manager, Vamshi Vemula, Project Engineer, Dr. Sastry Putcha and Chief Engineer

This paper presents the results from a case study on the comparison of two strain acquisition instrumentation technologies, Geokon rebar strainmeters and Embedded Data Collectors (EDC) for the DC Water Main Pump Station project, in Washington D.C. These two instrumentation systems were installed by AVER in a single 18-inch (0.45 m) diameter augercast pile (with one-1.25 inch (3.175 cm) dywidag bar) at critical locations to determine the load transfer mechanism and establish a comparison between strain/load measured with these two systems along the pile. A quick static load test was performed on the test pile as per ASTM D1143 standard. Prior to the installation of the pile, a 24-inch (0.6 m) diameter outer casing was installed to the proposed cutoff elevation of -22.5 feet (-6.85 m) to discount the frictional resitance within the upper overburden zone. The pile was then drilled through the outer casing to the tip elevation of -65.02 feet (-19.8 m) with inner casing within the overburden zone. Strainmeters along with EDC were installed on dywidag bar at various locations and then wet set into the concrete following auger retrieval. The loads measured with EDC and Geokon sensors were within 15% percent of each other.

 article #2607; publication #1032 (IC-2017)