Auto-Controlled Menard Pressuremeter: A Novel Tool for Optimal Use of the Pressuremeter

摘要

The pressuremeter test is an in situ controlled load-deformation test that is performed on the wall of a borehole using a radially expanded cylindrical probe. From the test readings (volume variation based on controlled pressure), a plane deformation stress-strain curve can be obtained for the soil. Since the initial prototype, the pressuremeter has consistently been improved in its design, and the latest version of the pressuremeter, which is called the "auto-controlled Pressuremeter" has been developed to address the issues of repeatability and accumulation of approximations in a test. This apparatus is fully automatic and autonomous, and manages all steps of the test as instructed by the operator. The auto-controlled Pressuremeter simplifies the work procedure for the operator, reinforces the reliability of the results, and reduces the time of set up. The present paper describes the auto-controlled pressuremeter, and compares it with the manual pressuremeter. The first part of the paper compares the deficiencies of the manual and auto-controlled Pressuremeter. In the second part, test results of the two types of pressuremeter that have been performed in similar conditions are presented and commented.