Consolidation behaviour of gassy mud : theory and experimental validation

The research consists of the development of a finite strain theory for gassy mud and numerical implementation in an existing saturated finite strain consolidation program. The numerical implementation has to be verified by using different discretisations. Special laboratory tests were used to validate the computer calculations. These tests consist of self weight column tests and oedometer tests on samples with an artificial gas production. Column tests were performed on samples with a natural gas production as well. In addition, a practical parameter test, the so-called GASCON test, has been developed for samples with a natural gas production. During this test the sample consolidated under the action of a hydraulic gradient, after a short period of self weight consolidation. A sensitivity analysis was performed in order to investigate the interaction between the presence of gas and other soil properties. Several distributions of gas content across the mud height were used. Finally, field measurements from the Slufter disposal site were used to validate the practical applicability of the computer program.