What is the standard value of liquid limit test?
Standard Values for Liquid Limit Test. Liquid limit is the water content at which a part of soil, cut by a groove of standard dimensions, will flow together for a distance of 1.25 cm under an impact of 25 blows in a standard liquid limit apparatus. The soil at the water content has some strength which is about 0.17 N/cm.sq. (17 gms/sq.cm.) .
What is liquid limit test of soil?
Liquid limit test of soil is done to get the information of fine-grain soil (cohesive soil) about the consolidation properties of soil while calculating allowable bearing capacity & settlement of the foundation.
What is the importance of liquid limit test in settlement analysis?
From liquid limit test, the compression index may be estimated, which is used in settlement analysis. If the natural moisture content of soil is higher than liquid limit, the soil can be considered as soft and if the moisture content is lesser than liquid limit, the soil is brittle and stiffer.
What if the liquid limit could not be obtained?
If sliding still occurs, the test is not applicable and it should be reported that the liquid limit could not be obtained. Liquid limit is the water content at which a part of soil, cut by a groove of standard dimensions, will flow together for a distance of 1.25 cm under an impact of 25 blows in a standard liquid limit apparatus.
What is the basic principle of liquid limit test?
THEORY: The liquid limit is the moisture content at which the groove, formed by a standard tool into the sample of soil taken in the standard cup, closes for 10 mm on being given 25 blows in a standard manner. This is the limiting moisture content at which the cohesive soil passes from liquid state to plastic state.
What is liquid limit and plastic limit test?
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.
What is the formula of liquid limit?
Determine Liquid Limit of Soil W1 = Mass (Weight) of Container (Bowl) W2 = Mass (Weight) of container (Bowl) with Sample wet Soil. W3 = Mass (Weight) of container (Bowl) with Sample dry soil.
Why plastic limit test is done?
Importance of Plastic Limit Test of Soil The value of the plastic limit is used to classify the fine-grained soils and evaluating the activities of clayey soil. 2. It indicates the toughness index of soil.
What is use of liquid limit of soil?
From liquid limit test, the compression index may be estimated, which is used in settlement analysis. If the natural moisture content of soil is higher than liquid limit, the soil can be considered as soft and if the moisture content is lesser than liquid limit, the soil is brittle and stiffer.
Why is liquid limit important?
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.
What is a high liquid limit?
A high liquid limit normally indicates a high compressibility and a high shrinkage/swelling potential. A high-plasticity index Ip generally results in a low shear strength. A low Ip means that a soil used as foundation will change significantly in consistency even with a small change in water content.
Why liquid limit and plastic limit is important?
The two limits associated with plasticity of soil are liquid limit (LL) and plastic limit (PL). These are used to calculate the plasticity index (PI = LL − PL), which is the measure of sensitivity of the soil to changes in its moisture content.
What is a plastic limit?
Plastic limit is defined as the water moisture content at which a thread of soil with 3.2mm diameter begins to crumble.
Why liquid limit and plastic limit is important?
The two limits associated with plasticity of soil are liquid limit (LL) and plastic limit (PL). These are used to calculate the plasticity index (PI = LL − PL), which is the measure of sensitivity of the soil to changes in its moisture content.
What is plastic limit in physics?
A load that exceeds the elastic limit deforms the material into the plastic region, which means that the material is permanently deformed when the load is removed. It does not return to the original configuration. The plastic limit occurs when the material reaches the maximum plastic deformation – the breaking point.
How do you determine the liquid limit and plastic limit of soil?
7:4115:48Determination of liquid limit and plastic limit of soil - YouTubeYouTubeStart of suggested clipEnd of suggested clipNow to analyze and interpret the results for liquid limit test we plot a graph between number ofMoreNow to analyze and interpret the results for liquid limit test we plot a graph between number of blows. And water content on a semi-log graph making use of readings recorded during various tests the
How to measure liquid limit?
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.
What is the liquid limit?
Liquid limit (LL) is defined as a limiting water content separating the viscous liquid state and plastic state of soil consistency.
Why can't you find the liquid limit of steel slag?
The liquid limit of steel slag cannot be obtained due to noncohesiveness or reduced cohesiveness of the particles. The plastic limit and the plasticity index of steel slag cannot be estimated due to the fact that steel slag is low-plastic in nature. View chapter Purchase book. Read full chapter.
How to determine maximum velocity of bubble?
(6.2) and (6.52) into Eq. (6.3) an expression for the acceleration for the bubble wall, R ¨, is derived. The maximum velocity R ˙ is determined by the condition that R ¨ = 0. The instantaneous value of the bubble radius at this point in time is
Which is higher, LL1 or LL2?
In Figure 4.8, LL1 is higher than LL2. In other words, soil 2 loses its shear strength and becomes liquid-like at a low water content than soil 1.
What is LL in soil?
The LL is defined as the lowest moisture content of soil at which it flows like a liquid. LL for both K&C-RCA and HRL-RCA was tested based on Q104A ( MTM, 2008) using a cone penetrometer method. A fraction of test samples (~ 300 g) passing 425 μm sieve were obtained using a mortar and pestle for the LL test. The test is based on the measurement of penetration of a standard stainless steel cone into the soil. The results from the LL tests are presented in Table 10.5 and are compared with the limits specified for recycled materials in MRTS35 (2018). Both K&C-RCA and HRL-RCA satisfied all types of recycled material classifications specified on MRTS35.
Is liquid limit meaningless for fine grained soil?
The identification and classification of fine-grained soil is done with the help of liquid and plastic limits. For cohesion-less soil, however, the liquid limit is meaning less. The potential for swelling can be indicative from high liquid limits coupled with a high plasticity index.
How to determine liquid limit?
The liquid limit is determined with a cup that is filled with soil paste. The cup is lifted and dropped from a specified height. From the number of blows that are necessary to close the groove the liquid limit is calculated.
What is the liquid limit?
Liquid limit (LL) is defined as a limiting water content separating the viscous liquid state and plastic state of soil consistency.
What are the Atterberg limits?
The Atterberg limits ( liquid limit , plastic limit, and shrinkage limit ) provide a very useful indication of the properties of the tailings. They have been used in soil mechanics for over 50 years, providing a measure of the moisture content at which a soil (tailings) changes from a liquid, to a plastic, to a semisolid, to a solid state. ( Moisture content is defined as the mass of water divided by the mass of dry solids.) In particular, the arithmetic difference between the liquid limit and the plastic limit (the plasticity index) is a particularly useful indicator of likely soil properties, including its potential to resist liquefaction.
How are liquid and plastic limits determined?
Liquid and plastic limits are determined by relatively simple laboratory tests that provide information about the nature of cohesive soils. Engineers use these tests extensively for the correlation of several physical soil parameters as well as for soil identification. Casagrande (1932 cited in Das, 1998) studied the relationship of the plasticity index to the liquid limit for a wide variety of natural soils. On the basis of the test results, he proposed a plasticity chart as shown in Fig. 9.1.
What is the liquidity index of plastic limit?
where w is the water content. At the Liquid Limit, the Liquidity Index is 1.0 and at the Plastic Limit it is 0, as shown in Figure 4.
What is LL in soil?
The LL is defined as the lowest moisture content of soil at which it flows like a liquid. LL for both K&C-RCA and HRL-RCA was tested based on Q104A ( MTM, 2008) using a cone penetrometer method. A fraction of test samples (~ 300 g) passing 425 μm sieve were obtained using a mortar and pestle for the LL test. The test is based on the measurement of penetration of a standard stainless steel cone into the soil. The results from the LL tests are presented in Table 10.5 and are compared with the limits specified for recycled materials in MRTS35 (2018). Both K&C-RCA and HRL-RCA satisfied all types of recycled material classifications specified on MRTS35.
Who classified the plasticity index in a qualitative manner?
Burmister (1949) classified the plasticity index in a qualitative manner ( Table 9.1 ). Reference values for consistency limits and plasticity of some naturally occurring cohesive soils are listed in Table 9.2.
Why is liquid limit important?
Why to Know Liquid Limit of Soil? Liquid limit of soil is a very important property of fine grained soil (or cohesive soil) 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 ...
What is the liquid limit value of soil used for?
Liquid limit value of soil is also used to calculate activity of clays and toughness index of soil.
What is Liquid Limit of Soil?
If we continue to add more water then again the soil will change its state of consistency from semi hard to plastic and finally reach a liquid consistency stage. When the soil reaches liquid consistency state, it has remain no cohesive strength to retain its shape under its own weight. It will start to deform its shape. So the amount of water which is responsible for this state of consistency of soil is called liquid limit of soil. In other words we can define liquid limit as
What happens to soil when it reaches liquid consistency?
When the soil reaches liquid consistency state, it has remain no cohesive strength to retain its shape under its own weight. It will start to deform its shape.
How much air dried soil is needed for a 425 micron sieve?
About 120 gm of air-dried soil from thoroughly mixed portion of material passing 425 micron I.S sieve is to be obtained.
What temperature is a thermometer controlled?
Thermostatically controlled with interior of non-corroding material to maintain the temperature around 105 0 C and 110 0 C
Can soil be remixed before a test?
The soil should then be remixed thoroughly before the test. A portion of the paste is placed in the cup of Mechanical Liquid Limit device and spread into portion with few strokes of spatula as possible.
What is the liquid limit of soil?
The liquid limit of a soil is the moisture content, expressed as a percentage of the mass of the oven-dried soil, at the boundary between the liquid and plastic states The moisture content at this boundary is arbitrarily defined as the liquid limit and is the moisture content at a consistency as determined by means of the standard liquid limit apparatus.
What happens if a sliding test is not applicable?
If sliding still occurs, the test is not applicable and it should be reported that the liquid limit could not be obtained.
Why is fen peat water below its liquid limit?
Usually fen peats have water content at or somewhat below their liquid limits. This is because partially decomposed plant material has a higher cation exchange capacity ...
Is the liquid limit of soil governed by the linear law of mixtures?
Based on the results obtained, it has been shown that the liquid limits of soil mixtures are not governed by the linear law of mixtures. While the shape of the sand was not found to influence the liquid limit, the size of the sand particles had a definite influence. First of all a grooved is made in the soil sample by using a standard grooving tool ...
Does time of mixing affect liquid limit?
It has been found that the liquid limit of certain materials is influenced by the time of mixing. There is a tendency, particularly noticeable in the case of decomposed dolerites and certain pedogenic materials, for the liquid limit to increase as the time of mixing is increased, although this increase will, of course, not continue indefinitely.
Why do we test liquid limits of soil?
Why to test Liquid limit of Soil? The liquid and plastic limits of soils are both dependent on the amount and type of clay in a soil and form the basis for the soil classification system for cohesive soils based on the plasticity tests. Besides their use for identification, the plasticity tests give information concerning the cohesion properties ...
How much soil sample should be mixed with distilled water?
About 120 g. of the soil sample passing through 425-micron IS Sieve shall be mixed thoroughly with distilled water in the evaporating dish or on the flat glass to form a uniform paste.
How thick is a flat glass plate?
Flat Glass Plate - 10 mm thick and about 45 cm square or larger (alternative to porcelain evaporating dish for mixing soil with water).
What is the purpose of plasticity tests?
Besides their use for identification, the plasticity tests give information concerning the cohesion properties of soil and the amount of capillary water which it can hold. They are also used directly in specifications for controlling soil for use in fill.
When to test light textured soil?
Note - 1 - Light textured soils (of low clay contept) may be tested immediately after thorough mixing of water.
What tool is used to measure length?
This length shall be measured with the end of the grooving tool or a ruler.
What is the practical significance of the liquid limit and plastic limit?
The practical significance of the Liquid limit and Plastic limit lies in their ability to reflect the types and amounts of clay minerals present in the fine fraction.
What is the plastic limit?
The plastic state reaches a consistency at which the soil ceases to behave as plastic and begins to break apart is Plastic Limit (P.L) the water content corresponding to an arbitrary limit between the plastic and semi-plastic state of consistency of soil. It is defined as the minimum water content at which a soil will begin to crumble ...
What is shrinkage limit?
In other words, shrinkage limit is defined as the maximum water content at which a reduction in water content will not cause a decrease in the volume of the soil mass. Also Read: Foundation in Black Cotton Soil.
What is water content corresponding to?
In other words, it is water content corresponding to the arbitrary limit between liquid and plastic state of consistency of soil.