Crucible swelling index, also known as free swelling index, in coal assay. They concluded that the soil clusters became larger and that binding with ohled to formation of floccules resulting in the. Where fsimax is the maximum predicted free swell index, fsimin is the minimum predicted free swell index respectively. If the free swell index of a soil is more than 100, the soil may be expansive. In this video we will learn how to determine the free swell index of soil. Free swell is the increase in volume of a soil, without any external constraints, on submergence in water. Standard test method for expansion index of soils1 this standard is issued under the. Engineering correlations for the characterisation of reactive soil behaviour for use in road design a dissertation submitted by. Characterization of the swelling properties of highly.
Free swell index is the increase in volume of a soil, without any external constraints, on submergence in water. Plasticity index pi, free swell index fsi%, swell potential and. The level of the soil in the kerosenegraduated cylinder shall be read as the original volume. The swelling pressure increases as the free swell index increases. The loadinduced strains after wetting from test method c can be used to estimate stressinduced settlement following.
Definition soil swelling is a term generally applied to the ability of a soil to undergo large changes in volume due to increased moisture content. The level of the soil in the distilled water cylinder shall be read as the free swell level. What is the procedure for free swell index test of soil. In this paper, a nondimensional modified free swell index is proposed, which removes the uncertainties present in the holtz and gibbs method. Prediction of fsi value by using hyperbola method international. Determination of free swell index of soils slideshare. Swell testing apparatus, swell test apparatus, swelling. Oedometer swell test the time versus swell response of the soils was obtained. Prediction of the free swell index of the expansive soil using artificial neural network has been presented in this paper. Engineering properties of bentonite stabilized with lime. Equipment apparatus oven1050c to 1100c, min balance 0. Free swell or differential free swell, also termed as free swell index, is the increase in volume of soil without any external constraint when subjected to submergence in water. The plots were drawn for the training and the testing data of the ann model and were shown in fig. If a soil does not contain any clay fraction, it cannot be expansive.
The maximum swelling index of 16ml2g occurred after the addition of 9. In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. The timeswell response of soils follow rectangular hyperbola. Determine free swell index of soil civil engineering portal. Estimation of swell index of fine grained soils using. Soil shrinkage characteristics in swelling soils 477 methods for assessing soil swellshrink potential a coefficient of linear extensibility, cole it characterizes the variation of soil volume from atm water retention i. Engineering properties such as compaction, unconfined compressive strength, consistency limits, percentage swell, free swell index, the california bearing ratio and the consolidation of bentonite stabilized with lime and phosphogypsum are presented in this paper. Key aspects that need identification when dealing with expansive soils include. The swell index or free swell test procedure is used to determine the general swelling characteristics of sodium bentonite clay. Swelling properties of expansive soils treated with.
Free swell will overstate the extent of the swelling. Classification procedures for expansive soils citeseerx. The measure of swell used by the corps of engineers is termed the free swell index. Prediction of free swell index for the expansive soil. Parameters such as cbr swell, shrink swell index, soil suction, weighted plasticity index, swelling pressure, weighted linear. A number in parentheses indicates the year of last reapproval. Input parameters for the artificial neural network model were plasticity index and shrinkage index, while the output was the free swell index. Data required for modeling were collected f rom the literature 312. May 14, 20 objective for determination of free swell index of soils reference standard is. Engineering correlations for the characterisation of. The amount of certain clay minerals that are present, such as montmorillonite and smectite, directly affects the shrinkswell capacity of soil.
Free swell is 2720 part 201977 experimentation all experiments were carried out from engineering point of view to identify the reduction in free swell index and to improve the engineering properties of black cotton soil. Characterization of the swelling properties of highly plastic. Free swell index fsi indicates the potential expansiveness of a soil. Pdf prediction of free swell index for the expansive soil using. It consists of pouring slowly 10 cm3 of oven dried soil passing a 425mm sieve into a 100 cm3 measuring jar.
Free swell index soil applied and interdisciplinary physics scribd. Pdf prediction of free swell index for the expansive. In this method, which is a standard method of practice specified by the bureau of indian standards is. For highly plastic soils the nature of curve of free swell index versus swelling pressure is upward concave while for low plasticity soils it is downward concave. The determination of free swell index also known as differential free swell of soil helps to identify the potential of a soil to swell which might need further detailed investigation regarding swelling and swelling pressures under different field conditions. Objective for determination of free swell index of soils reference standard is. The purpose of this study is to compare the performances of widely used empirical swell index equations and to develop new empirical equations and a neural network based estimation technique for swell index by using the results of conventional oedometer and index test results. Im just not sure how you convert free swell into a design value for the foundation. In order to determine the relationship with the highest regression coefficient between the index parameters and swell index, regression analyses were performed between w n, ll, e 0, g n, g d and swell index. Procedure soil sample upto 500 gram is taken from desired site and kept in oven for 24 hours at 1001100c, so that sample becomes. There is still a great necessity for civil and geotechnical engineering practice in the city to deepen the understanding of the mechanical properties of the soils in this zone of the city. The free swell index of the soil shall be calculated as follows. The swelling index stays constant after addition of 8. To realize foundaiton distress, the swell pressures have to exceed the foundation stress.
Determine free swell index of soil civil engineering. The free swell is then reported as the increase in the volume of the soil expressed as a percentage of the. Atterberges limits, free swell index, swelling pressure, c. This method allowed for the characterization of the swelling properties of the soil within 24 hours of the start of testing. Subbituminous coals and lignite are classified as freeburning coals. The test results indicate that, the free swell index linear variation with the non swelling residual soil.
If the free swell index is lower than 100, the soil may be treated as nonexpansive. Prediction of free swell index for the expansive soil using. For the soil samples index properties are calculated and soils are classified accordingly. Free swell index test, swelling pressure test, swell percent. In many cases, the shrinking and swelling of expansive clays in response to mois. Free burning coals do not have the same swelling characteristic free swelling index of 0. The soil samples, kerosene being a nonpolar liquid does not cause swelling of the soil. The shrinkswell index of clay refers to the extent certain clay minerals will expand when wet and retract when dry. No doubt, the free swell test will give you some measure that the soil is prone to swell. Engineering properties of bentonite stabilized with lime and. D653 terminology relating to soil, rock, and contained fluids d698 test methods for laboratory compaction characteristics of soil using standard effort 12 400 ftlbfft3 600. Correlation between swelling index of bentonite clay and. Prediction of swelling behavior of expansive soils using. In this method, the free swell index is defined by the eq.
The modified free swell index is shown to bear unique correlations with liquid limit volume basis and percent swell of oedometer specimens compacted to proctor optimum conditions. Swelling properties of expansive soils treated with chemicals. Mar 05, 2018 determination of free swell index of soils 1. Soil with a high shrinkswell capacity is problematic and is known as shrinkswell soil, or expansive soil. Im just not sure how you convert free swell into a. Atterberg limits, grain size distribution, optimum water content, maximum water content, swelling pressure, methylene blue value mbv, vi modified free swell index mfsi and swell potential of the mixtures were assessed. Another additive that as been found to be quite promising in reducingh the swelling characteristics and improving the engineering behavior of expansive soils. Freeburning coals do not have the same swelling characteristic free swelling index of 0. In an effort to extend the knowledge about the mechanical behavior of clays in this part of barranquilla, this. Expansive soil was collected at a depth of 1 m from the ground level from the town of amalapuram, ap, india. Swellconsolidation characteristics of fibrereinforced. Free swell index, yes we will learn this important soil test in this video, for more detail visit our website follow us o. Expansive soil of a high free swell index fsi was used in the experimental study.
In this method 10 grams of ovendried soil sample passing. Modified free swell index for clays astm international. Free swell index test of soil, fsi test of soil asper is. Expansive soil, swelling potential, methylene blue test, modified. Traditional freeswell testing to achieve the same level of characterization required approximately 30 days for the highly plastic clay evaluated in the study. Methodology swelling tests in model tank the soil sample of height 80 mm was compacted corresponding to maximum dry density and optimum moisture content in a mould of dia 150 mm and height of 180. Free swell index test of soil, fsi test of soil asper is code. The possibility of damage to structures due to swelling of expensive clays need be identified, at the outset, by an investigation of those soils. Remoulded compacted soil, when soaked in water, absorbs water and swells. As the clay percentage in a soil increases, it exhibits more swelling pressure and free swell index.
Nylon fibre was used to reinforce the expansive soil specimens. Experience has shown that the plasticity index pi is an excellent indicator of. Standard test method for expansion index of soils1. The expansive soil specimens were prepared in the laboratory by mixing kaolinite and bentonite at different percentages. Another additive that as been found to be quite promising in reducingh the swelling characteristics and improving the engineering behavior of expansive soils is fly ash. Correlation between swelling index of bentonite clay and the. Free swell index test is conducted by taking 10g of oven. To determine the free swell index of soil as per is. Subbituminous coals and lignite are classified as free burning coals.
Bentonite swell index astm d5890 global synthetics. Prediction of swelling characteristics of remoulded and. Swell test apparatus is designed to determine the swelling pressure developed by soil specimens moulded to desired densities at known moisture content. Both caking and free burning coals can be burned without difficulty in pulverized coalfired boilers. Swelling index may refer to the following material parameters that quantify volume change. The process began with the selection of input parameters and the output parameter. May 20, 2018 free swell index, yes we will learn this important soil test in this video, for more detail visit our website follow us o. In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to. Differential free swell index is the increase in volume of soil, without any external constraints, only on submergence in water.
Pdf on feb 19, 2019, rakesh kumar dutta and others published prediction of free swell index for the expansive soil using artificial neural. Definition free swell index is the increase in volume of a soil, without any external constraints, on submergence in water. Artificial neural network the methodology used for modeling the prediction of the free swell index of the expansive soil using a neural network has been presented in this section. The index properties of the soil are presented in table 1. Standard test methods for onedimensional swell or collapse. The content of the lime and phosphogypsum varied from 0 to 10 %. Pdf prediction of free swell index for the expansive soil.
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