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Fine-grained soils subjected to seismic loading often exhibit instability or failure of slopes, foundations, and embankments. To understand the behavior of clay soils under multiple earthquake loads, kaolinite samples were prepared and tested in the laboratory using a cyclic simple shear device. Each sample was subjected to two cyclic events separated by different degrees of reconsolidation periods to simulate different levels of excess pore water pressure dissipation. The results indicated that the degree to which excess pore water pressure generated during the first cyclic event was dissipated affected the cyclic resistance of the soil during the second cyclic event. The post-cyclic undrained shear strength was also found to be a function of the degree to which excess pore water pressure from the first cyclic load was allowed to dissipate prior to the application of the second cyclic load.
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A Study on Thermal Consolidation of Fine Grained Soils Using Modified Consolidometer
In order to fully understand the thermo-hydro-mechanical behavior of the geotechnical infrastructures, the effects of temperature variations on soil properties and soil behavior have to be studied. Hydraulic conductivity, strength, volume change, moisture content, and pore pressure generation and dissipation rates depend on temperature variations. Thermal loading might induce excess pore water pressure and volumetric changes. Temperature changes in the fine-grained soils will cause expansion in water and soil particles. Since the coefficient of expansion for soil particles is much smaller than that for water, a generation of pore water pressure is expected. This thermally induced pore water pressure and then its dissipation during the relaxation period results in a time dependent consolidation. Thermal consolidation in fine grained soil is more dominant and can be irreversible in normally consolidated clay. However, the volumetric changes of highly over consolidated soil caused by temperature increment is reversible by temperature reduction. In this research, a modified consolidation testing device is used to study the effect of temperature increments (e.g., increasing step by step temperature increments to 80ºC) on the consolidation of fine grained soils. In another words the effect of temperature increments during the test on the consolidation process is studied. Time of applying the heating, target temperature, and initial void ratio are parameters affecting the rate and the amount of consolidation in the samples.
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- Award ID(s):
- 1804822
- PAR ID:
- 10104922
- Date Published:
- Journal Name:
- Geo-congress 2019
- Page Range / eLocation ID:
- 148 to 156
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1061/9780784482117.014
