CALIBRATION CHAMBER SIZE EFFECTS ON PENETRATION RESISTANCE IN SAND

Calibration chamber tests provide an effective way to study cone penet ration resistance in sands under controlled conditions. Calibration ch amber tests are performed in large soil samples with known densities, consolidated to desired stresses, and subjected to known boundary cond itions. Results from calibration chamber tests can be used to establis h the relationship between cone resistance, soil density, and stress s tate. However, the penetration resistance measured in a calibration ch amber differs from that measured in the free field because of chamber size and boundary condition effects. There has been considerable uncer tainty about these effects, precluding use of the results of calibrati on chamber research with greater confidence. In this paper, a penetrat ion resistance theory recently developed is used to quantify chamber s ize effect, to investigate the factors it depends on, and to show how to correct calibration chamber test penetration resistance values to f ree-field conditions. The theoretical results are compared with availa ble experimental results.