A View of Pressuremeter Testing in North America
J. Benoît, J.A. Howie
Soils and Rocks, São Paulo, 37(3): 211-231, September-December, 2014 | PDF
The pressuremeter was introduced to North America by Ménard in 1957. It consists of a cylindrical probe which is inserted into the ground in a borehole, by self-boring or by pushing, and is expanded against the soil or rock to obtain a pressure-expansion curve. Interpretation methods based on cavity expansion theory applied to realistic models of soil behavior allow derivation of in situ lateral stress, stiffness, strength and volume change characteristics of the material being tested. Since its introduction, the pressuremeter test (PMT) has been a popular topic of research but has not gained wide acceptance in geotechnical engineering site characterization practice which, in North America, is still dominated by the Standard Penetration Test (SPT) and more recently by the piezocone (CPTu). Over the same period, the PMT has become the dominant tool for site investigation and foundation design in France. There, the PMT is used empirically based on a very large amount of load testing and experience. This paper examines the use of the PMT in North American practice, discusses its strengths and weaknesses, identifies trends in its use for site characterization and geotechnical design and identifies possible reasons for its lack of adoption by industry. We conclude that the PMT is not competitive with other techniques such as the CPTu and SPT for general site characterization where such tests are possible but that the PMT offers great potential to provide geotechnical design parameters in problematic materials such as hard, very dense or gravelly soils, residual, saprolitic or lateritic soils, soft and fractured rocks, frozen ground and ice. The PMT also has application in all soils where high consequences of failure require very detailed analysis and design. We also emphasize the need for improvements in the education of geotechnical practitioners on the use of the pressuremeter.
Submitted on March 28, 2014; Final Acceptance on December 15, 2014; Discussion open until April 30, 2015.