G-I Lunch Meeting - July 20, 2023 

Please join us for the G-I Cross USA Lecturer 2022-2023, Timothy D. Stark Ph.D., PE, F.ASCE, D.GE, presenting on "CSL and TIP Testing on Drilled Shafts"

This presentation will discuss the use of thermal integrity profile (TIP) and crosshole sonic logging (CSL) tests to identify installed defects in drilled shafts at three Illinois test sites. The findings indicate TIP can identify defects outside of the rebar cage, whereas CSL is efficient in detecting defects at the bottom of the drilled shaft. Furthermore, interpreting TIP data for drilled shafts is commonly done by discerning the general trend of shaft temperatures with depth or by concrete yield plots using construction logs. This presentation will present the results of numerical modeling of concrete heat of hydration during curing of drilled shafts and compare the results to TIP measurements for these three Illinois test drilled shafts. The 3D numerical results match the peak temperatures and temperatures at one-half the time to peak temperature measured by TIP wires at different depths for all three test drilled shafts. The validated 3D numerical model can be used to facilitate interpretation of TIP data for future projects. If time permits, this presentation will present the Modified Standard Penetration Test (MSPT) for drilled shaft design in weak rocks.

Timothy D. Stark Ph.D., PE, F.ASCE, D.GE

Timothy D. Stark is a Professor of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign with an expertise in Geotechnical Engineering. Dr. Stark has been conducting research and teaching on shallow and deep foundations for over twenty-five (25) years. Dr. Stark has received a number of awards for his research, teaching, and service activities including: 2023 J.E. Jennings Award, South African Institution of Civil Engineering; 2023 Martin S. Kapp Memorial Lecturer, American Society of Civil Engineers (ASCE) Metropolitan Section; 2022-2023 Cross-USA Lecturer, ASCE; 2022 T.H. Wu Lecture at The Ohio State University; 2019 George H. Norman Medal, ASCE; Best Paper in Geosynthetics International Journal, 2016; 2015 James M. Hoover Lecture at Iowa State University; Thomas A. Middlebrooks Award, ASCE, 2013 and 1998; Associate Editor Award, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2012; Journal of Legal Affairs and Dispute Resolution in Engineering Scholarly, Paper, ASCE, 2011; R.S. Ladd D18 Standards Development Award, Standard Designation, ASTM, 2014, 2011, 2002; R.M. Quigley Award from the Canadian Geotechnical Society, 2003.

1.0 PDH will be issued for attending this event.