There are so many shaly sand conduction models, and most of them are only used in some local area, and have their limitations. So far, there is no theoretical model that can be used commonly and efficiently .In this p...There are so many shaly sand conduction models, and most of them are only used in some local area, and have their limitations. So far, there is no theoretical model that can be used commonly and efficiently .In this paper, based on some existing models, and combining with the knowledge of the researched area, we designed out a new conduction model. The total conductivity of the rock is the combining result from free water in inter granular porous, micro pore water and the clay bound water. It can well describe many electric conduction characteristics of shaly sand. In order to make it useable in practice, we also provide some methods for interpreting the pore components with comprehensive logging data.展开更多
The non-isothermal deformation of soft mudrocks or clay soils is one of the most critical issues in energy and environmental related geotechnics.Clay-related geomaterials hold complex microstructure and mineral compos...The non-isothermal deformation of soft mudrocks or clay soils is one of the most critical issues in energy and environmental related geotechnics.Clay-related geomaterials hold complex microstructure and mineral composition,which brings difficulty in investigating their thermo-mechanical behaviors.Previous studies pay little attention to the difference between a thermal plastic strain and the strain from clay dehydration.In this study,a new constitutive model is proposed for describing the thermoelastoplastic behaviors of clayey soils under water-saturated condition.The effect of temperature variation and mechanical loading on elastoplastic strains and dehydration are investigated.The thermodynamics laws and the unconventional plasticity are applied to quantify the thermo-mechanical behavior.The irreversible strain is captured by using Cam-Clay plasticity and subloading yield surface concept.The dehydration strain is described by utilizing a novel method based on generalized thermodynamics approach and Helmholtz free energy function.The internal variables,and the first and second laws of thermodynamics are applied in the model.The hardening rule is established by implementing the laws of physical conservation,energy dissipation,and plastic flow.The proposed model is validated using specially designed thermal consolidation tests on laboratory prepared heavily consolidated clayey soils and some published data of clayey soils with different geological origins.展开更多
文摘There are so many shaly sand conduction models, and most of them are only used in some local area, and have their limitations. So far, there is no theoretical model that can be used commonly and efficiently .In this paper, based on some existing models, and combining with the knowledge of the researched area, we designed out a new conduction model. The total conductivity of the rock is the combining result from free water in inter granular porous, micro pore water and the clay bound water. It can well describe many electric conduction characteristics of shaly sand. In order to make it useable in practice, we also provide some methods for interpreting the pore components with comprehensive logging data.
基金funded by Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery Grant Canada(Grant No.RGPIN-2017-05169).
文摘The non-isothermal deformation of soft mudrocks or clay soils is one of the most critical issues in energy and environmental related geotechnics.Clay-related geomaterials hold complex microstructure and mineral composition,which brings difficulty in investigating their thermo-mechanical behaviors.Previous studies pay little attention to the difference between a thermal plastic strain and the strain from clay dehydration.In this study,a new constitutive model is proposed for describing the thermoelastoplastic behaviors of clayey soils under water-saturated condition.The effect of temperature variation and mechanical loading on elastoplastic strains and dehydration are investigated.The thermodynamics laws and the unconventional plasticity are applied to quantify the thermo-mechanical behavior.The irreversible strain is captured by using Cam-Clay plasticity and subloading yield surface concept.The dehydration strain is described by utilizing a novel method based on generalized thermodynamics approach and Helmholtz free energy function.The internal variables,and the first and second laws of thermodynamics are applied in the model.The hardening rule is established by implementing the laws of physical conservation,energy dissipation,and plastic flow.The proposed model is validated using specially designed thermal consolidation tests on laboratory prepared heavily consolidated clayey soils and some published data of clayey soils with different geological origins.