Instructional Drilling Video

Jason T. DeJong (jdejong@ucdavis.edu) & Ross W. Boulanger (rwboulanger@ucdavis.edu)

General Description

This 35-minute video presents an overview of typical drilling and sampling methods in Geotechnical Engineering practice. Topics include types of drill rigs, rotary wash drilling, solid and hollow stem auguring, SPT testing, thin-walled tube sampling, Pitcher barrel sampling, rock coring, and sample disturbance.

This video was produced as an undergraduate independent study project (ECI-199) at UC Davis in 1996. A revision was completed in 2000 based on feedback from friends and colleagues who have used it in their undergraduate and graduate courses. The revisions are significant enough (including a new voice!) to warrant replacing older copies.

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We would appreciate a brief email letting us know if you download the video and find it useful in your teaching and/or learning about geotechnical engineering. After all, our motivation in sharing the video is to see it get used. Thanks.

Video Link

You Tube

Questions for a Class

Here are an example set of questions that we often use when the video is assigned as part of a homework set.

• What are the typical types of drill rigs?
• What drill rig is most common?
• What drill rig would be best suited for soft, saturated soils?
• What are the common drilling methods? • What method is best for drilling collapsing soil? Why?
• What method would be best for shallow holes (<25’) in cohesive soil?
• Explain how soil cuttings are brought to the surface for each method. Which method would be better for large, gravel sized particles?
• Under what circumstances must casing be used?
• What method is best for sampling rock?
• What size samples are obtained from a conventional split-spoon sampler?
• Explain how the standard penetration resistance, or N value, is determined? What is this a measure of?
• What is the effect of using sample liners on the SPT N value?
• How is a thin-walled Shelby tube sample obtained?
• What is a thin-walled sample more suitable for consolidation tests?
• What is the objective of the piston-sampler?
• Why is the sample “less disturbed” compared to the thin-walled Shelby tube sample?
• What is the effect of sample disturbance on consolidation and strength behavior?
• Are high quality undisturbed samples needed for site investigations? Why?

 Copyright

Copyrights for this video, in any format, belong to Jason T. DeJong and Ross W. Boulanger. Permission is granted only for nonprofit use as an educational aid by students, teachers, or practitioners. Permission is hereby granted for reproducing the video in any format for nonprofit educational use only. Reproduction of this video in any format, in part or in whole, for any commercial purpose is strictly prohibited without the express written permission of the authors. Please cite the following reference when using the video:

DeJong, J.T. and Boulanger, R.W. (2000) “Introduction to Drilling and Sampling in Geotechnical Practice”, Educational Video, 2nd Edition, Department of Civil and Environmental Engineering, University of California, Davis, 35 min.