Free Swell Ratio and Clay Mineralogy of Fine-Grained Soils

Abstract

Soil being a widely used material in the field of civil engineering, hence, its study is very important. Cohesive soil (especially black cotton soil) often does not fully satisfy the engineering properties a requirement for their use in sub grade of pavements or as a base to lay foundations. Such soils are generally not preferred in the construction industry due to their high shrink-swell property. In this experimental program, a study of index properties and free swell ratio of clay-sand mixture with varying percentages of sand ranging from 10% to 50%. A study of the variation of the liquid limit, plastic limit, specific gravity and free swell ratio with increase in addition of cohesion less soil is studied in cohesive soils containing kaolinite and montmorillonite clay minerals. It is observed that the Liquid Limit, Specific Gravity and Free Swell Ratio decrease with the addition of sand whereas Plastic limit increases.

Impact of slaking shale behaviour on damage of engineering structures, Saudi Arabia

“…The FSR ranged from 1.01 to 1.07 with an average of 1.06, which indicates low expansivity according to the classification by Prakash and Sridharan (2004). The swell potential (S p ) from the 1D oedometer of the shale was found to be quite low, ranging between 1.12 and 1.75% with an average of 1.50%.…”

“…The activity of the shale (activity index) was defined according to the paper by Skempton (1953) as activity (A c ) = PI/percentage of clays finer than 2 mm. Prakash and Sridharan (2004) defined the free swell ratio (FSR) as the ratio of equilibrium sediment volume of 10 g oven-dried soil passing a 425 mm sieve in distilled water (V d ) to that in kerosene (V k ). Thus, the FSR can be calculated as…”

Swell–Shrink Behavior of Rubberized Expansive Clays during Alternate Wetting and Drying

“…2 51. 41 Sridharan and Nagaraj [54] USCS classification CH ASTM D2487-11 Free swell ratio, FSR 3 2.91 Prakash and Sridharan [55] Degree of expansivity High Prakash and Sridharan [55] Optimum water content, w opt (%) 26.00 ASTM D698-12 Maximum dry unit weight, γ dmax (kN/m 3 ) 15.07 ASTM D698-12 Unconfined compressive strength, q u (kPa) 4 112.62 ASTM D2166-16 Splitting tensile strength, q s (kPa) 4 13.57 ASTM C496-17…”

“…The liquid limit and plasticity index were, respectively, measured as w L = 59.60% and I P = 32.32%, from which the soil was characterized as clay with high plasticity (CH) in accordance with the Unified Soil Classification System (USCS). The free swell ratio (FSR) was measured as 2.91, from which the soil was graded as highly expansive [55]. Other soil properties, as supplied by the manufacturer, included a neutral pH of 7.80, a specific surface area of 42.75 m 2 /g, and a cation exchange capacity of 21.65 meq/100 mL.…”

Swell–Shrink–Consolidation Behavior of Rubber–Reinforced Expansive Soils

“…The chemical compositions of the kaolinite and bentonite, as supplied by the manufacturer, are provided in Table 2. The free swell ratio for kaolinite, bentonite, and the kaolinite-bentonite mixture was 1.19, 7.53, and 2.91, from which these soils were graded into "lowly expansive," "very highly expansive," and "highly expansive" with respect to the classification criteria proposed by Prakash and Sridharan (2004), respectively.…”