Comparison Between Statnamic And Static Load Testing Of Drilled Shafts In Varved Clay

Static and STATNAMIC (STN) rapid load test (RLT) was performed on 3-drilled shafts. The purpose of the RLT part of the study was to obtain data in support of FHWA research on innovative load testing methods. The research site is located at the National Experimentation Research Site (NGES) in Amherst Massachusetts and is underlain by Connecticut valley varved clay. Two of the tested shafts were constructed without planned defects and the third with manufactured defects to evaluate current non-destructive integrity testing (NDE) methods. Quick Load Test (QLT) and Constant Rate of Penetration (CRP) static axial load tests were performed on two shafts to plunging failure. Good agreement between static and RLT derived static failure loads was attained for a 5% failure criterion (load at a movement equal to 5% of shaft diameter).