Improved Calibration and Correction Techniques for Pressuremeters
Equipment calibration is essential to the pressuremeter test procedure in order to obtain meaningful results. This paper assesses the accuracy of the standard calibration procedures for a monocell pressuremeter probe. The probe was inserted into sets of instrumented aluminum tubes of various lengths and diameters. The pressure distribution acting against the cavity wall was determined for different levels of probe inflation. Continuous information about the inflation resistance of the probe was also obtained as well as the correlations between the applied pressure, the volume of fluid injected, and the average probe diameter. A more reliable procedure for membrane reaction calibration is then recommended, as well as a new volumetric correction for end perturbations. The influence of low temperatures on the overall behavior of the equipment is also discussed.