Relationship between suction and shear strength parameters of compacted METU campus clay

Tilgen, Hüseyin Pars
In this study, the relationship between soil suction and shear strength parameters of compacted METU campus clay were investigated at different moisture contents. Soil samples were tested at optimum moisture content (i.e. w=20.8%), at dry side of optimum moisture content (i.e. w=14.8%, 16.8%, 18.8%) and at wet side of optimum moisture content (i.e. w=22.8%, 24.8%, 26.8%). Direct shear tests were performed to measure shear strength parameters (c', F') and soil suctions were measured by filter paper method after direct shear tests. These relationships were also investigated on soaked samples. The trends for suction, angle of internal friction and cohesion, which change on the dry side and wet side of optimum moisture content, were analyzed. The compacted METU campus clay gains granular soil fabric at the dry side of optimum moisture content. As moisture content increases, cohesion increases up to optimum moisture content and then decreases. But angle of internal friction decreases as moisture content increases. Soaking affects the samples more which are on the dry side of optimum moisture content. The soil suction (total suction and matric suction) affects the shear strength, and an increase in soil suction increases the shear strength.


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Çokça, Erdal (2002-11-19)
The purpose of this study was to investigate the relationship between methylene blue value, initial soil suction and the swell percentage of expansive soil samples. In this study, commercially processed kaolinite and bentonite mineral clays were mixed in preselected proportions to obtain soil samples possessing a wide range of plasticities and different swell percentages. The methylene blue adsorption tests, suction measurements using a thermocouple psychrometer technique and standard free swell tests in oe...
Effects of compaction moisture content on the shear strength of an unsaturated clay
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Çokça, Erdal (1999-12-01)
This paper discusses the effect of Fly ash on the engineering properties of expansive soils. As reviewed in literature, many previous investigations have shown promising results for improvement of expansive soil after stabilization with Fly ash. Laboratory tests have been conducted on expansive soils obtained from three different regions in Khartoum state. Various percentages of Fly ash such as 0%, 10%, 20%, 25%, and 30% by weight of soil were added to the three soils and their inf...
Comparison Of Formulae For Shear Strength Of Unsaturated Soils
Zehtab, Kaveh Hassan; Toker, Nabi Kartal; Ahmadiadli, Mohammad (2012-06-30)
During last 60 years many research studies have been conducted on calculation of shear strength of unsaturated soils and effects of matric suction on it. Several formulae are developed for predicting shear strength of unsaturated soils, based on strength tests on unsaturated soils. A variety of experimental techniques and laboratory equipment are used for unsaturated shear strength characterization. This study discusses the accuracy of shear strength prediction for unsaturated soils with three different for...
Comparative study of soil water characteristic curve prediction methods
Ahmadiadli, Mohammad; Huvaj Sarıhan, Nejan; Toker, Nabi Kartal; Kürkçü, Mefküre Gamze (2012-06-30)
The soil-water characteristic curve (SWCC), which defines the relation between soil suction and water content, plays a key role in geotechnical studies of the unsaturated soils. Some researchers such as Brooks & Corey (1968), Van Genuchten (1982) and Fredlund& Xing (1994) have proposed curve fitting equations for SWCC. Fitting equations to the laboratory test data obtained from direct measurement of water content versus changes in matric suction is the most reliable method, but it is expensive and time cons...
Citation Formats
H. P. Tilgen, “Relationship between suction and shear strength parameters of compacted METU campus clay,” M.S. - Master of Science, Middle East Technical University, 2003.