Influence of ethanol/water mixture on the undrained shear strength of pure clays

Bulletin of Engineering Geology and the Environment - Tập 71 - Trang 389-398 - 2011
Giovanni Spagnoli1,2, Helge Stanjek3, Asuri Sridharan4
1Department of Engineering Geology and Hydrogeology, RWTH Aachen University, Aachen, Germany
2Fugro Consult GmbH, Pfungstadt, Germany
3Clay and Interface Mineralogy, RWTH Aachen University, Aachen, Germany
4Department of Civil Engineering, Indian Institute of Science, Bangalore, India

Tóm tắt

The mechanical properties of clays are highly dependent not only on the stress/strain ratio to which the material is subjected but also on the chemistry of the pore fluids which in turn affects the intergranular or the effective stresses. Atterberg limits and vane shear tests were performed with different pore fluids in order to observe how the fine-grained material mechanically responded. The diffuse double layer theory has been used to interpret the data of vane shear tests in order to explain the variation of geotechnical responses with the different clays. Van der Waals forces and double layer forces were obtained and capillary forces calculated. The results show that while for kaolinite and illite the chemistry of the pore fluids has no influence on the water content and hence on the mechanical behaviour of the material, Na-smectite shows a strong correlation between the dielectric constant of the pore fluids and an increase in undrained shear strength. The data obtained extends an understanding of the influence of the dielectric constant (ε) of the pore fluids on the geotechnical properties of fine-grained materials.

Tài liệu tham khảo

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