Description:FIELD OF THE INVENTION
The present invention relates to a method for producing engineered soil with reduced moisture content and improved compressive strength suitable for various geotechnical applications.
BACKGROUND OF THE INVENTION:
Embodiments of the present invention generally relate to a method for producing good quality engineered soil and particularly to a method for producing good quality engineered soil with reduced moisture content and improving soil stress-strain relationship curve through an addition of optimum fibre dosage.
Description of Related Art
Soil reinforcement is an ancient technique for improving properties of soil such as, stress-strain relationship, soil strength, bearing capacity, and so forth. Naturally available soil has weak strength and behaves like a plastic material with a fragile failure pattern. There are some reinforcement techniques that are used to improve soil characteristics and properties. These conventional reinforcement techniques comprise continuous and random inclusion of fabrics, grids, or fibres into the soil. However, soil deformation usually occurs due to prevailing moisture content, applied load, duration of the load applied, and nature of the soil. Although the currently available reinforcement techniques are used to modify the existing soil by inclusion and confinement; however, the soil characteristics still vary according to the mineral and moisture content present in it.
At present, different kinds of soil reinforcement techniques are used for strengthening and stabilizing naturally occurring weak soil. However, different kinds of soil contain different minerals and thus needs a particular method for increasing its strength. Such kind of soil should be modified through strength enhancement procedure to increase a particular soil's respective behavior. Currently, no commercial or industrial method is available that can provide reduced swelling characteristics and effective strengthening of all types of soil based on its moisture content.
There is thus a need for a method that can produce good quality engineered soil with the reduced moisture content in a more efficient manner.
None of the prior art indicate above either alone or in combination with one another disclose what the present invention has disclosed. This invention relates to method for producing good quality engineered soil with reduced moisture content
SUMMARY OF THE INVENTION
Embodiments in accordance with the present invention provides a method for producing engineered soil with reduced moisture content and improved compressive strength. The method involves the use of specific additives in precise proportions to achieve the desired properties. The resulting engineered soil exhibits optimal moisture content and maximum dry density, along with improved compressive strength characteristics. The present invention provide a method for producing good quality engineered soil. The method comprising steps of: pulverizing soil collected from a depth ranging from 20 Centimeters (cm) to 25 Centimeters (cm) by using a ball mill; drying the pulverized soil at a pre-defined temperature; removing lumps and foreign materials from the dried soil by using a wooden mallet; treating fibres by immersing the fibres in an alkali solution for a first pre-defined amount of time; crushing the fibres into fine grain sized fibres upon drying out the wet fibres in sunlight; adding a pre-defined level of water content into the soil from a pre-defined height by using a pour dropping method such that the pre-defined height is 10 Centimetres; mixing the added water, the soil, and a pre-defined percentage of the treated fibres by using a hand mixer for a second pre-defined amount of time by leaving one minute gap between a mixing process after every four minutes such that the pre-defined percentage of the treated fibres is added slowly upon allowing one full minute of rotation of the hand mixer to prepare the engineered soil; and curing the engineered soil under three conditions selected from an open­ air condition, plastic sheet, and in controlled desiccation for 12 days for determining soil stress strain characteristics under varying moisture content.
Embodiments of the present invention may provide a number of advantages depending on their particular configuration. First, embodiments of the present application may provide a method for producing good quality engineered soil that may be designed with specific fibre and reduced moisture content.
Next, embodiments of the present application may provide a method for producing good quality engineered soil that may be designed for preventing soil deformation due to prevailing moisture content.
Next, embodiments of the present application may provide a method for producing good quality engineered soil that may be designed for reducing swelling characteristics of soil.
Next, embodiments of the present application may provide a method for producing good quality engineered soil that may be designed for improving soil stress-strain relationship curve.
Next, embodiments of the present application may provide a method for modifying characteristics of naturally occurring weak soil by utilizing a specific process.
Next, embodiments of the present application may provide a method for modifying naturally occurring weak soil for improved strength and sturdiness by utilizing a strength enhancement procedure.
Next, embodiments of the present application may provide a method for producing stronger engineered soil that may be dependent on its mineral content.
These and other advantages will be apparent from the present application of the embodiments described herein.
The preceding is a simplified summary to provide an understanding of some embodiments of the present invention. This summary is neither an extensive nor exhaustive overview of the present invention and its various embodiments. The summary presents selected concepts of the embodiments of the present invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the present invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
The illustrated embodiments of the subject matter will be understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and methods that are consistent with the subject matter as claimed herein, wherein:
Figure 1: UCS (kPa) after curing the engineered soil for predetermined durations
Figure 2: Composition in specific proportions to prepare the soil mixture
The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
Detailed description of the Invention
The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
In addition, the descriptions of "first", "second", “third”, and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include at least one of the features, either explicitly or implicitly.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
In an embodiment of the present invention, a pre­ defined quantity of soil, lime, metakaolin, glass fiber, sodium silicate, and supplementary cementitious materials (SCMs) may be collected from various sources.
Further, in an embodiment of the present invention, the materials may be pulverized to break into small sized particles having a size less than 2 Millimeters (mm). In such embodiment of the present invention, the soil may be pulverized by using a pulverization tool such as, but not limited to, a roller mill, an impact mill, and so forth. In a preferred embodiment of the present invention, the pulverization tool may be a ball mill. Embodiments of the present invention are intended to include or otherwise cover any type of the pulverization tool including known related art and/or later developed technologies.
Further, in an embodiment of the present invention, the pulverized soil may be dried at a pre-defined temperature by using a drying method. The pre-defined temperature may be in a range of 63 degrees Celsius to 66 degrees Celsius, in an embodiment of the present invention.
In a preferred embodiment of the present invention, the pre-defined temperature may be 65 degrees Celsius. The drying method may be, but not limited to, a microwave drying method, and so forth. Embodiments of the present invention are intended to include or otherwise cover any type of the drying method including known related art and/or later developed technologies.
In an embodiment of the present invention, lumps and foreign materials may be removed from the dried soil by using a lump removing tool. The lump removing tool may be, but not limited to, spade, hoe, and so forth. In a preferred embodiment of the present invention, the lump removing tool may be a mallet. The mallet may be made up of any material such as, but not limited to, rubber, plastic, and so forth. In a preferred embodiment of the present invention, the mallet may be made up of wood. Embodiments of the present invention are intended to include or otherwise cover any type of the material of the mallet including known related art and/or later developed technologies. Embodiments of the present invention are intended to include or otherwise cover any type of the lump removing tool including known related art and/or later developed technologies. In an embodiment of the present invention, the soil may be passed through a sieve of 1.3 Millimeters to ensure that no lumps are left in the soil.
In an embodiment of the present invention, the glass fibres may be waste fibres, natural fibres, and so forth. In a preferred embodiment of the present invention, the fibres may be man-made fibres that may be intact and without any segregation. In an embodiment of the present invention, the fibres may be treated by first immersing the fibres into an alkali solution for a first pre-defined amount of time to make the fibres durable and non-corrosive. In a preferred embodiment of the present invention, the alkali solution may be, 3M Sodium Hydroxide (NaOH) solution. Further, in a preferred embodiment of the present invention, the first pre-defined amount of time may be 24 hours.
Further, the wet fibres may be taken out from the alkali solution and may be dried in sunlight until the fibres get completely dried, in an embodiment of the present invention. The dried fibres may be crushed into fine grain sized fibres to mix the crushed fibres 102 into the soil, in an embodiment of the present invention.
In a preferred embodiment of the present invention, the plastic material may be a High-Density Polyethylene (HOPE) plastic. Embodiments of the present invention are intended to include or otherwise cover any type of the material that may be durable including known related art and/or later developed technologies.
In an embodiment of the present invention, if the level of the water content added in the soil is more than the optimum moisture content, then it is called as a wet of optimum. In another embodiment of the present invention, if the level of water content is less than the optimum moisture content, then it is called as a dry of optimum. The optimum moisture content (OMC) and maximum dry density (MDD) of the soil mixture are determined through standard laboratory tests. The OMC is found to be 22%.
Moreover, A soil with high swell index is considered “unsuitable” for use as embankment fill material and in case the sub soil is having high free swell index then suitable “ground improvement measures” may be needed before constructing embankment on such soil. Actual magnitude of swelling pressure developed depends upon the dry density, initial water content, surcharge loading and several other environmental factors. The swell index is calculated; the level of soil in the kerosene graduated cylinder shall be read as the original volume of the soil samples, kerosene being a non-polar liquid does not cause swelling of the soil. The level of the soil in the distilled water cylinder shall be read as the free swell level. Free swell Index, percent = [(Vd-Vk)/Vk] x100.
Further, a hand mixer may be used for mixing the added water, the soil 100 and a pre-defined percentage of the treated fibres for a second pre-defined amount of time by leaving one minute gap between a mixing process after every four minutes, in an embodiment of the present invention. The second pre-defined amount of time may be 14 minutes, in a preferred embodiment of the present invention. In an embodiment of the present invention, the pre-defined percentage of treated fibres 102 may be added slowly after allowing one full minute of rotation of the hand mixer to ensure that the water is completely mixed in the soil 100. In an embodiment of the present invention, the hand mixer may be rotated at a pre-defined speed to thoroughly mix the water, the soil 100 and the treated glass fibres. In a preferred embodiment of the present invention, the pre-defined speed of the hand mixer may be 400 rotations per minute (rpm). In an embodiment of the present invention, different percentages of the treated fibres may be added to the wet soil 100. The different percentages of the treated fibres may be 0.1% and 0.2%, in an embodiment of the present invention. The treated fibres may be mixed thoroughly to the wet soil 100 to ensure proper dispersion of the fibres, in an embodiment of the present invention.
In an embodiment of the present invention, the mixed soil may be tilted multiple times for a third pre-defined amount of time by using a machine mixer to increase the mixing of water. In a preferred embodiment of the present invention, the third pre-defined amount of time may be 10 minutes. In an embodiment of the present invention, the mixed soil may be the engineered soil that may be produced by the mixture of the soil, the water and the fibres. Further, the engineered soil 106 may be filled in molds for testing where the engineered soil may be cured under three conditions such as, in an open-air condition, in a plastic sheet, and in a controlled desiccation.
The graph represents the stress strain curves for the engineered soil, when the engineered soil 106 is cured for 3 days, 7 days and 14 days in the open-air condition.
The method for producing engineered soil with reduced moisture content and improved compressive strength comprises the following steps:
201 Selection of Raw Materials: The raw materials used in the production of engineered soil include soil, lime, metakaolin, glass fibre, sodium silicate, and supplementary cementitious materials (SCMs). The soil should be selected based on its properties such as particle size distribution, plasticity, and swell index.
202 Preparation of Soil Mixture: The soil mixture is prepared by blending the raw materials in specific proportions. The proportions of each additive are as follows: 0.5% lime, 1% metakaolin, 0.1% glass fibre, 2% sodium silicate, and 2% supplementary cementitious materials (SCMs). These additives are mixed thoroughly with the soil to ensure uniform distribution.
203 Determination of Optimum Moisture Content (OMC) and Maximum Dry Density (MDD): The optimum moisture content (OMC) and maximum dry density (MDD) of the soil mixture are determined through standard laboratory tests. The OMC is found to be 22% and the MDD is 1.43 g/cc.
204 Evaluation of Liquid Limit (LL%) and Plastic Limit (PL%): The liquid limit (LL%) and plastic limit (PL%) of the soil are determined to assess its plasticity characteristics. The LL% is the moisture content at which the soil no longer flows like a liquid, while the PL% is the moisture content at which the soil can no longer be remolded without cracking. The soil mixture exhibits 59% of LL and 28% of PL.
205 Calculation of Swell Index: The swell index of the soil mixture is calculated to evaluate its potential for swelling. The swell index is calculated; the level of soil in the kerosene graduated cylinder shall be read as the original volume of the soil samples, kerosene being a non-polar liquid does not cause swelling of the soil. The level of the soil in the distilled water cylinder shall be read as the free swell level. Free swell Index, percent = [(Vd-Vk)/Vk] x100. The swell index is determined by measuring the volume of soil in a graduated cylinder containing distilled water and comparing it to the volume in a cylinder containing kerosene. The calculated swell index percentage is found to be 32%.
Where:
Vd= the volume of soil in the cylinder containing distilled water
Vk= the volume of soil in the cylinder containing kerosene.
206 Curing of Engineered Soil: The engineered soil is cured for different durations, namely 3, 7, and 14 days, to assess its compressive strength over time.
207 Measurement of Unconfined Compressive Strength (UCS): After curing, the unconfined compressive strength (UCS) of the engineered soil is measured using standard testing procedures. The UCS values obtained after 3, 7, and 14 days of curing are 6.3 kPa, 29.9 kPa, and 20.9 kPa, respectively.
While the invention has been described in connection with what is presently considered to be the most practical and various embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements within substantial differences from the literal languages of the claims.
Advantages of the Invention:
The method for producing engineered soil with reduced moisture content and improved compressive strength offers several advantages:
• Enhanced suitability for various geotechnical applications
• Improved stability and durability
• Reduced risk of swelling and shrinkage
• Cost-effective and environmentally friendly
• Enhanced Workability: Denser packing allows for easier handling and pouring of the concrete.
• Increased Strength: A denser structure translates to stronger concrete, improving its ability to withstand loads.
• Boosted Durability: Denser packing can also lead to improved resistance to cracking and wear, making the concrete more durable.
This invention takes sustainability a step further by incorporating SCM which evaluates the environmental impact of the concrete throughout its entire lifespan, from material sourcing to disposal. This provides a more comprehensive picture of the concrete's sustainability compared to traditional options.
The invention utilizes data from the casting and testing phase to further refine the mix design. This allows for continuous improvement and ensures the concrete meets the desired performance and sustainability goals.
These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
, Claims:1. An engineered soil with reduced moisture content comprising: 0.5% lime, 1% metakaolin, 0.1% glass fibre, 2% sodium silicate, and 2% supplementary cementitious materials (SCMs); wherein the composition is blended in said specific proportions to prepare a soil mixture with enhanced properties.
2. A method for producing engineered soil with reduced moisture content, comprising the steps of:
a) selecting raw materials including soil, lime, metakaolin, glass fibre, sodium silicate, and supplementary cementitious materials (SCMs);
b) pulverizing lime, metakaolin, glass fibre, sodium silicate, and supplementary cementitious materials (SCMs) collected from a depth ranging from 20 Centimeters (cm) to 25 Centimeters (cm) by using a ball mill;
c) drying the pulverized materials at a temperature ranges from 63 degrees Celsius to 66 degrees Celsius and removing lumps and foreign materials from the dried mixture of materials by using a wooden mallet;
d) preparing a soil mixture by blending said raw materials in specific proportions, wherein said proportions comprise 0.5% lime, 1% metakaolin, 0.1% glass fiber, 2% sodium silicate, and 2% supplementary cementitious materials (SCMs);
e) adding a pre-defined level of water content into the soil mixture from a pre-defined height by using a pour dropping method and for determining soil stress strain characteristics under varying moisture content;
f) determining optimum moisture content (OMC) and maximum dry density (MDD) of the soil mixture;
g) evaluating liquid limit (LL%) and plastic limit (PL%) of the soil mixture;
h) calculating swell index of the soil mixture; and
i) curing the engineered soil for predetermined durations to measure unconfined compressive strength (UCS).
3. The method as claimed in claim 1, wherein the optimum moisture content (OMC) of the soil mixture is 22% and the maximum dry density (MDD) is 1.43 g/cc.
4. The method as claimed in claim 1, wherein the engineered soil shows 59% of liquid limit (LL%) and 28% of plastic limit (PL%).
5. The method as claimed in claim 1, wherein the swell index of the soil mixture is calculated to be 32%; the level of the soil in the distilled water cylinder is read as the swell index of engineered soil.
6. The method as claimed in claim 1, wherein the unconfined compressive strength (UCS) of the engineered soil after 3, 7, and 14 days of curing is measured to be 6.3 kPa, 29.9 kPa, and 20.9 kPa, respectively.