Experimental study and constitutive modeling of volume change behavior in unsaturated soils

2020 ◽  
Vol 80 (1) ◽  
pp. 679-689
Author(s):  
Wugang Li ◽  
Qing Yang ◽  
Zhijia Xue ◽  
Wenhua Liu ◽  
Yuan Hua
Keyword(s):  
Experimental Study ◽  
Volume Change ◽  
Constitutive Modeling ◽  
Unsaturated Soils ◽  
Change Behavior ◽  
Volume Change Behavior

A hyperbolic model for volume change behavior of collapsible soils

1998 ◽  
Vol 35 (2) ◽  
pp. 264-272 ◽  
Author(s):  
G Habibagahi ◽  
M Mokhberi
Keyword(s):  
Bulk Modulus ◽  
Water Content ◽  
Volume Change ◽  
Unsaturated Soils ◽  
Computer Programs ◽  
Constitutive Relationship ◽  
Degree Of Saturation ◽  
Hyperbolic Model ◽  
Change Behavior ◽  
Volume Change Behavior

Finite element computer programs are frequently used to analyze and design embankments and similar earth structures. In most of the available computer programs, lack of a proper constitutive relationship to deal with volume change when an increase in the degree of saturation occurs, namely collapse phenomena, is a major handicap. In this paper, volume change results obtained from isotropic compression tests conducted on unsaturated compacted soil specimens are presented. Dependence of the bulk modulus of the soil on water content is investigated. Next, a hyperbolic formulation for volume change behavior of unsaturated soils taking into account variation of soil water content is presented. This hyperbolic model relates mean applied stress, volume change, and water content and represents a three-dimensional surface, the so-called "state surface". Suitability of the proposed model to predict collapse phenomena is verified by examining the model prediction against available experimental data.Key words: hyperbolic, unsaturated soil, collapse, volume change, suction pressure, bulk modulus.

scholarly journals Volume change behavior of unsaturated soils under non-isothermal conditions

2011 ◽  
Vol 56 (23) ◽  
pp. 2495-2504 ◽  
Author(s):  
GuoQing Cai ◽  
ChengGang Zhao ◽  
Yan Liu ◽  
Jian Li
Keyword(s):  
Volume Change ◽  
Unsaturated Soils ◽  
Isothermal Conditions ◽  
Change Behavior ◽  
Volume Change Behavior

Validation of the Volume Change Behavior in SFG Model Using a Soil Consolidation Test and a Soil Water Characteristic Curve Experiment

2012 ◽  
Vol 446-449 ◽  
pp. 1918-1921
Author(s):  
Yi Yi Zhou ◽  
Jie Li ◽  
Wen Hu Li
Keyword(s):  
Volume Change ◽  
Unsaturated Soil ◽  
Constitutive Modeling ◽  
Characteristic Curve ◽  
Constitutive Models ◽  
Soil Consolidation ◽  
Change Behavior ◽  
Volume Change Behavior ◽  
Reasonable Model ◽  
Different Soils

Constitutive modeling in unsaturated soil is always a big challenge in Geo-technique problems. Since Alonso et al suggested the Basic Barcelona Model (BBM) in 1990. Many researchers contribute works on constitutive models in last two decades. The SFG model presented by Sheng, Fredlund and Gens describes the mechanical and hydraulic behaviors of an unsaturated soil accurately. It is currently considered the most reasonable model for unsaturated soil. In this paper, the authors attempts to prove the volume change behavior in SFG model by two basic unsaturated soil experiments in testing two different soils. The experimental data and the fitting processes are provided.

Improvement of Strength and Volume-Change Properties of Expansive Clays with Geopolymer Treatment

2021 ◽  
pp. 036119812110018
Author(s):  
Rinu Samuel ◽  
Anand J. Puppala ◽  
Aritra Banerjee ◽  
Oscar Huang ◽  
Miladin Radovic ◽  
...  
Keyword(s):  
Volume Change ◽  
Carbon Dioxide Emissions ◽  
Expansive Soils ◽  
Linear Shrinkage ◽  
Plasticity Index ◽  
Specimen Preparation ◽  
Expansive Clays ◽  
Change Behavior ◽  
Volume Change Behavior ◽  
Lower Carbon

Expansive soils are conventionally treated with chemical stabilizers manufactured by energy-intensive processes that significantly contribute to carbon dioxide emissions globally. Geopolymers, which are synthesized from industrial byproducts rich in aluminosilicates, are a viable alternative to conventional treatments, as they are eco-friendly and sustainable. In this study, a metakaolin-based geopolymer was synthesized, and its effects on the strength and volume-change behavior of two native expansive soils from Texas, with a plasticity index over 20 were investigated. This paper elaborates on the geopolymerization process, synthesis of the metakaolin-based geopolymer, specimen preparation, and geopolymer treatment of soils. Comprehensive material testing revealed two clays with a plasticity index over 20. They were each treated with three dosages of the metakaolin-based geopolymer and cured in 100% relative humidity for three different curing periods. The efficiency of geopolymer treatment was determined by testing the control and geopolymer-treated soils for unconfined compressive strength (UCS), one-dimensional swell, and linear shrinkage. Field emission scanning electron microscope (FESEM) imaging was performed on the synthesized geopolymer, as well as on the control and geopolymer-treated soils, to detect microstructural changes caused by geopolymerization. A significant increase in UCS and reduction in swelling and shrinkage were observed for both geopolymer-treated soils, within a curing period of only 7 days. The FESEM imaging provided new insights on the structure of geopolymers and evidence of geopolymer formation in treated soils. In conclusion, the metakaolin-based geopolymer has strong potential as a lower-carbon-footprint alternative to conventional stabilizers for expansive soils.

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