Design of a Large Calibration Chamber

Abstract The design and operation of a conceptually simple, low-cost chamber for calibration of cone penetrometers and other in situ devices is described. The chamber weighs over 5500 kg and houses a 4400-kg soil sample that is 1.5 m in diameter and height. Operations in the chamber are automated using a self-equilibrating hydraulic insertion frame, a soil pluviation system for sand placement, a vacuum unit for removing sand, and an automatic data acquisition system. The results from a series of cone penetration tests in Monterey No. 0/30 sand, using standard and miniature cones, are also discussed. These tests indicate that the chamber design was successful and also that nearly homogeneous samples could be prepared at different relative densities using interchangeable rainer plates.