Get the NCHRP Synthesis 418 – Pile Criteria From Test Pile Data
Dan’s Speaking Schedule
September 12-13, 2012: Concrete used in Drilled Shaft Construction - ADSC/DFI Drilled Shaft Seminar - Denver, Colorado
October 26, 2012: Factors Affecting the Selection and Use of Drilled Shafts for Transportation Infrastructure Projects - 26th Central Pennsylvania Geotechnical Conference - ASCE/DFI - Hershey, Pennsylvania
Other DBA Team Speaking Appearances
John Turner (September 12-13, 2012): Analysis & Design of Drilled Shafts - ADSC/DFI Drilled Shaft Seminar - Denver, Colorado
John Turner (September 12-13, 2012): Techniques for Drilled Shaft Construction - ADSC/DFI Drilled Shaft Seminar - Denver, Colorado
Another paper featured in the December 2011 issue of the DFI Journal was authored by Steve and Dan, along with Dr. Bob Parsons at the University of Kansas.
The paper describes a program of lateral load tests on six drilled shafts installed in a loess deposit at a site in Wyandotte County, Kansas. The lateral load test data, along with site characterization data that included CPT data, were used to develop a hyperbolic model to generate p-y curves for use in lateral load analyses in cemented soils. The model should be applicable to many “c-phi” soils (soils with both a cohesion intercept and a friction angle, such as cemented soils). Degradation of the static soil model to account for cyclic loading effects is included in the new model.
This paper was originally published in the DFI Journal,Vol. 5 No. 2, December 2011, the bi-annual Journal of the Deep Foundations Institute. DFI is an international technical association of firms and individuals involved in the deep foundations and related industry. The DFI Journal is provided to DFI members at no cost electronically or can be purchased in print at www.dfi.org.
This paper is one of several papers and articles published form a series of research projects by KU and the Kansas DOT. Some of the previous work can be found at these links:
Papers by Dan, Steve, and Tim that were included in the GeoFlorida 2010 conference have been uploaded to our Publications page. Dan and Steve co-authored a paper on the test program of the base grouted drilled shafts for the Audubon Bridge. Tim co-authored a paper with Willie NeSmith of Berkel and Company Contractors, Inc. on plate load testing of displacement grout columns. Dan was also a co-author with several others on a paper on jet grouting for improved pile lateral capacity.
One area of work we are frequently involved in is data analysis and evaluation of lateral load tests performed by the Statnamic testing device (learn more at the website of Applied Foundation Testing). The mathematics involved in the data reduction can be quite formidable as you interpret the dynamic load-response to an equivalent static load-response. Regardless of the math behind it, watching a test can be pretty cool. It is a whole lot of work for a brief moment of load, but in some situations it can be more economical than a traditional load test.
The video below is from a test on 170-foot long, 32-inch outside diameter steel pipe pile with 0.75"-inch wall thickness. The pile was filled with concrete that included an instrumented rebar cage.
