Liquid limit is the water content where the soil starts to behave as a liquid. Liquid limit is measured by placing a clay sample in a standard cup and making a separation (groove) using a spatula. The cup is dropped till the separation vanishes. The water content of the soil is obtained from this sample.

Liquid Limit (LL) is the water content at which soil changes from a plastic to a liquid state when the soil specimen is just fluid enough for a groove to close when jarred in a specified manner. Plastic Limit (PL) is the water content at the change from a plastic to a semi-solid state.

Calculate the plastic limit wp by dividing the “weight of moisture” by the “dry weight of sample” and multiply by 100. Plasticity Index (Ip) of a soil is the numerical difference between its Liquid Limit and its Plastic Limit.

Determination of Plastic Limit is as important as Liquid Limit so as to ascertain Plasticity Index, Ip of the soil. The plastic limit of a soil is the moisture content, expressed as a percentage of the weight of the oven-dry soil, at the boundary between the plastic and semi-solid states of consistency.

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Value of liquid limit is used to classify fine grained soil. It gives us information regarding the state of consistency of soil on site. Liquid limit of soil can be used to predict the consolidation properties of soil while calculating allowable bearing capacity & settlement of foundation.

Yes ? it can have have a negative value. A negative liquidity index means that the soil is drier that the plastic limit. It merely describes the moisture condition of a soil with respect to its index limits.

Soils with a high PI tend to be clay, Those with a lower PI tend to be silt, and.

The liquidity index (LI) is used for scaling the natural water content of a soil sample to the limits. 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.

Borrow materials shall have a liquid limit (LL) between 40 and 60 and a plasticity index (PI) between 15 and 30 (ASTM D4318). Materials shall be free of topsoil, organic or frozen material, roots, stumps, brush, rocks larger than 3.0”, subsoil, debris, vegetation, and other foreign matter.

So in this relationship we can see at plastic limit consistency index value is 1 so liquidity index value is zero and at liquid limit consistency index value is zero so liquidity index value is 1.

Yes 🙂 it can have have a negative value. A negative liquidity index means that the soil is drier that the plastic limit. Liquidity Index (LI) is a measure of the consistency of the soil. It shows in what part of its plastic range a given sample of soil lies.

If liquidity index value is equal to zero, then the soil will behave similar to a plastic material. Suppose the value of LI will exceed one, soil will flow similar to a liquid and the structure of soil particles will collapse.

Stress–strain curves. As for other types of materials, a compression test can be used to evaluate the plasticity of clays. The typical test curve gives information about the modulus of elasticity, yield strength, maximum deformation and rupture strength.

The plasticity and liquidity indexes are the basic geotechnical parameters of cohesive soils. The liquidity index (IL) determines the consistency and physical state of soil. The plasticity index refers to the type of soil, its degree of cohesion.

Clay is a ‘plastic’ material because we can mould it into different shapes, which is a property of plastic. But clay is not a polymer because polymers are made up of monomer units while clay is not made up of monomer units. Clay is a mixture of compounds.

A plasticity chart , based on the values of liquid limit (WL) and plasticity index (IP), is provided in ISSCS to aid classification. The ‘A’ line in this chart is expressed as IP = 0.73 (WL – 20). Depending on the point in the chart, fine soils are divided into clays (C), silts (M), or organic soils (O).

Plasticity refers to things that can still change their shape or function. The brain is something with high plasticity: if you have a brain injury, other parts of the brain can change to pick up the slack. Anything that is capable of evolving or being reshaped has plasticity.

It indicates the fineness of the soil and its capacity to change shape without altering its volume. A high PI indicates an excess of clay or colloids in the soil. Its value is zero whenever the PL is greater or equal to the LL. The plasticity index also gives a good indication of compressibility (see Section 10.3).

Plasticity, ability of certain solids to flow or to change shape permanently when subjected to stresses of intermediate magnitude between those producing temporary deformation, or elastic behaviour, and those causing failure of the material, or rupture (see yield point).

Plastic limit is defined as the water moisture content at which a thread of soil with 3.2mm diameter begins to crumble.

If the soil obviously is dirty, the classification will be either (c) silty gravel ( GM ). graded sand (SP), and the dirty sands shall be classified as (c) silty sand (SM), if the fines have little or no plasticity; or (d) clayey sand ( SC), if the fines are of low to medium or high plasticity ( SIt 3.2. 2 ).

Neuroplasticity – or brain plasticity – is the ability of the brain to modify its connections or re-wire itself. For example, there is an area of the brain that is devoted to movement of the right arm. Damage to this part of the brain will impair movement of the right arm.

Summary. The biological process of neuronal plasticity allows for changes in neural circuitry, which can amend the structure and function of the brain. These changes allow learning and memory to work properly, and deviations in its working are related to neuropsychiatric disorders.