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Evaluation of consolidation parame ters in CL tests
[...].. .Evaluation of consolidation parameters in CL tests; theoretical and practical aspects 407 Table 1 Geotechnical properties of soils and conditions of CL tests Average velocity of CL test Initial soil properties Type of soil Sample no Attaining Sr = 1 in the course of CL test level III level IV Water content w [%] Initial degree of saturation Sr 0 [-] Ds/Dt [kPa s–1]... the CCL value increases constantly which is related to a rapid increase of the t(T = 1) value in the course of the test After changing the co-ordinate system into CCL vs TCL we obtain an equal route of the curves It is worth mentioning that, when the consolidation process is presented in the CCL vs TCL system diagram, for other types of pore water pressure distribution interesting results are obtained... factor Selecting the fluid flow factor is crucial for proper use of the time scale effect for long-term forecast Evaluation of consolidation parameters in CL tests; theoretical and practical aspects CONCLUSIONS 1 The consolidation process in the continuous loading condition possesses attributes that make it different from classic consolidation under constant loading 2 Application of the introduced dimensionless... dimensionless parameters CCL vs TCL makes it possible to present characteristic diagrams of pore water pressure changes depending only on the loading procedure 3 The algorithms presented allow for comparison of the interpretation methods applied up to now for CL tests with theoretical solutions based on the classical Terzaghi model of consolidation 4 On the basis of the CCL vs TCL relation the value of the consolidation. .. converting the CCL vs s system into CCL vs TCL the experimental curve runs close to the theoretical one and TCL values first decrease and than return up along the theoretical curve (Fig 10) This is because of a significant increase of t(T = 1) during the test This may be a result of too high a load rate and a limited possibility of pore water pressure dissipation in the consolidated soil, especially in clays... important information concerning assessment of the load rate in CL tests The tests should be carried out with reference to the results of proper load velocity according to the field conditions (Dobak, 1995, 1999) DISCUSSION The suggestion for assessment and selection of the optimum CL consolidation parameters presented above is closely con- 15.2 0.80 6 10 nected with Terzaghi’s solution Terzaghi’s theory of. .. method for one dimensional consolidation proporties of soils using controlled — strain loading Am Soc Test Mater., 1998 BUTTERFIELD R and EL-BAHEY M E (1995) — A simple non-linear finite-strain consolidation analysis In: Compression and Consolidation of Clayey Soils (eds H Yoshikuni and O Kusakabe) Balkema Rotterdam DAVIS E H and RAYMOND G P (1965) — A non-linear theory of consolidation Geotechnique,... distribution and their consistency with the assumptions of the filtration consolidation theory Acknowledgements I wish to express my thanks to prof Z Glazer, prof L Wysokiński and prof J Gaszyński for inspired discuss and advices REFERENCES ALMEIDA M S S., MARTINS I S and CARVALHO S R L (1995) — Constant rate of strain consolidation of Singapore marine clay — discusion to paper: Lee K et al., 1993 Geotechnique,... Terzaghi’s solution for CL tests enables selection of the fluid flow aspect in the process analysed The CCL vs TCL diagrams have been prepared on the basis of Terzaghi’s theory Therefore the cv value estimated using MD tests mainly reflects the seepage aspect of the consolida- tion process This is why cv values obtained using the MD method are higher than those estimated using previously applied methods... Gdańskiej DOBAK P (2003) — Loading velocity in consolidation analysis Geol Quart., 47 (1): 13–20 DOBAK P and KOWALCZYK S (2008) — Consolidation parameters of Neogene green clays from Bełchatów — a study on CL test interpretation Geologija, Suplement, 50: 520–525 Vilnius DUNCAN J M (1993) — Limitations of conventional analysis of consolidation settlement J Geotech Engin., 119 (9): 1333–1359 FREDLUND 123doc.vn