What is sensitivity and thixotropy?
Unconfined compressive strength & Sensitivity of clays: Sensitivity, St is defined as the ratio of unconfined compressive strength of clay in undisturbed state to unconfined compressive strength of a same clay in remoulded state at unaltered water content. …
Is milk thixotropic?
Milk and evapo- rated milk behave as Newtonian fluids, but con- centrated milk behaves as a non-Newtonian fluid. Cream and yogurt are also non-Newtonian fluids. Other dairy products such as whipped cream, yogurt, ice cream, and cheese have been characterized by their viscoelastic nature.
What is soil sensitivity?
Soil sensitivity is defined as the ratio of peak to remoulded shear strength. Problem soil materials are those that show large strength losses on disruption, resulting in catastrophic failure, liquefaction and long run-out distances. Field investigations indicated that sensitive soils are common in the Tauranga region.
How do you calculate soil activity?
It can be calculated as a ratio of difference between natural water content, plastic limit, and liquid limit: LI=(W-PL)/(LL-PL) where W is the natural water content. Activity of soil can be defined as ration of plasticity index to clay fraction as percentage.
What is rheology in pharmacy?
Definition of Rheology • Rheology is the science/physics that concerns with the flow of liquids and the deformation of solids. • Study of flow properties of liquids is important for pharmacist working in the manufacture of several dosage forms, viz., simple liquids, gels, ointments, creams, and pastes.
What causes thixotropy?
Thixotropy arises because particles or structured solutes require time to organize. Some fluids are anti-thixotropic: constant shear stress for a time causes an increase in viscosity or even solidification. Fluids which exhibit this property are sometimes called rheopectic.
Why is blood thixotropic?
Blood is a non-newtonian fluid with visco-elastic, shear thinning and thixotropic properties. A thixotropic fluid is a fluid whose viscosity is a function not only of the shearing stress, but also of the previous history of motion within the fluid .
What is the difference between cohesive and cohesionless soil?
Texture differences in soils result from the types of rock that make up a particular area. So non-cohesive soil environments contain little to no clay or fine particles while cohesive soils contain high amounts of clay and fine particles.
What does Pseudoplastic mean?
1 : lacking the capacity for major modification or evolutionary differentiation — compare euryplastic, stenoplastic. 2 : characterized by or being flow in which the rate of flow (as of solutions of rubber or gelatinous substances) increases faster than normally in relation to the shearing stress.
What are the properties of cohesive soil?
“Cohesive soil” means clay (fine grained soil), or soil with a high clay content, which has cohesive strength. Cohesive soil does not crumble, can be excavated with vertical sideslopes, and is plastic when moist. Cohesive soil is hard to break up when dry, and exhibits significant cohesion when submerged.
What is rheology in food science?
Food rheology is the study of the rheological properties of food, that is, the consistency and flow of food under tightly specified conditions. The acceptability of food products to the consumer is often determined by food texture, such as how spreadable and creamy a food product is.
What is non-cohesive material?
Noncohesive soils are mineral soils that exhibit granular characteristics in which the grains remain separate from each other and do not form clods or hold together in aggregates of particles. Noncohesive soils also may be called cohesionless soils or granular soils. Clean sand and gravel are noncohesive soils.
Is mayonnaise thixotropic?
Indeed, mayonnaise has been shown to be shear thinning, viscoelastic, and thixotropic, it has a yield stress, and in some studies apparent wall slip has been observed.
What is sensitivity?
: the quality or state of being sensitive: such as. a : the capacity of an organism or sense organ to respond to stimulation : irritability. b : the quality or state of being hypersensitive. c : the degree to which a radio receiving set responds to incoming waves.
Is sand cohesive or cohesionless?
Cohesionless soils are defined as any free-running type of soil, such as sand or gravel, whose strength depends on friction between particles (measured by the friction angle, Ø).
What is thixotropy of clay?
Thixotropy is a distinctively rheological (time-dependent) phenomenon, which is found in many complex materials, especially colloidal systems as fine-grained soils. Clays are materials that can recover their initial strength after remoulding.
What is Cohesionless soil with example?
Cohesionless soil is soil that contains elements that do not stick together. Soil analysis prior to construction provides information critical to the success of trenchless operations. Examples of cohesionless soil are sand and gravel. Cohesionless soil is also known as frictional soil.
What is cohesion in soil mechanics?
By definition, cohesion is the stress (act) of sticking together. Yet, in engineering mechanics, particularly in soil mechanics, cohesion refers to shear strength under zero normal stress, or the intercept of a material’s failure envelope with shear stress axis in the shear stress-normal stress space.
What is a cohesive material?
Definition. Cohesive soils are fine-grained, low-strength, and easily deformable soils that have a tendency for particles to adhere. Examples of cohesive soils include sandy clay, silty clay, clayey silt, and organic clay.
Is soil a classification?
In the Indian Standard Soil Classification System (ISSCS), soils are classified into groups according to size, and the groups are further divided into coarse, medium and fine sub-groups. The grain-size range is used as the basis for grouping soil particles into boulder, cobble, gravel, sand, silt or clay.
What does rheology mean?
Rheology is the study of how materials flow or deform under an applied force.
Which strength theory is applicable to cohesive frictional soil?
Mohr – Coulomb’s strength theory 2. Purely cohesive soil (C – soil) :- • These are the soils which exhibit cohesion but, the angle of shearing resistance,φ = 0.