In-situ Observations on Back-pressures and Pore Water Pressures in Composite Foundation with Stone Columns

Valuable data were obtained from field observations on back-pressures and pore water pressures in composite foundation with stone columns during construction of a building. The measured back-pressures under the foundation and their stress concentration factors were in good agreement with those from the loading tests. It is shown that the monitored excess pore water pressures during construction do not increase greatly but dissipate quickly.