AN ASSESSMENT OF CHAMBER SIZE EFFECTS IN THE CALIBRATION OF INSITU TESTS IN SAND

Calibration chamber tests are currently used to establish correlations between in situ testing data and the engineering properties of sands, and play an important role in the understanding of in situ tests. Practical and economic considerations require that calibration chambers must be of limited size, and so the chosen boundary conditions have an important effect on the results. An assessment is made of the effects of chamber size on the measured values of the limit pressure obtained from the pressuremeter test and on the cone resistance values from the cone penetrometer test. Experimental and numerical data suggest that the effect of the proximity of the chamber boundaries is significant for dense and medium sand, and is observed even for loose sand.