Roughness and Unit Side Resistances of Drilled Shafts Socketed in Clay Shale and Limestone
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 134, Issue 9
Abstract
Rock socketed drilled shafts are being used increasingly to support heavily loaded structures. Rock sockets provide resistance to the load through a combination of side and base resistances. In this study, the effect of drilling tools such as an auger and a core barrel on the unit side resistance was investigated. A total of four field studies were performed on clay shale (compressive strength of ) and limestone (compressive strength of ). Borehole roughnesses produced by the different types of drilling tools in clay shale and limestone were measured using a laser borehole roughness profiler developed in this study to measure roughness to in the boreholes. Based on the results of this study, it was observed that the drilling tools developed different socket roughnesses, which in turn affected the side resistances of the rock socketed drilled shafts.
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Acknowledgments
The writers are forever grateful to the late Michael W. O’Neill (1940–2003) for his valuable contributions to this research project and are honored to have worked with him very closely during the field tests. May his soul rest in peace. Most of the sampling and testing work reported here was funded by the Texas Department of Transportation as a part of a larger research project to improve the design of drilled foundations in soft rock. Sponsors are not responsible for any are findings reported in this study.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 134 • Issue 9 • September 2008
Pages: 1272 - 1279
Copyright
© 2008 ASCE.
History
Received: Mar 8, 2006
Accepted: Jun 28, 2006
Published online: Sep 1, 2008
Published in print: Sep 2008
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