Description:FIELD OF THE INVENTION
[0001] The present disclosure relates to a field of construction materials and pavement engineering. Particularly, the present disclosure relates to a styrene butadiene rubber modified pervious concrete reinforced with geogrid. The present disclosure also provides a method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid. The present disclosure provides better mechanical properties and can be a promising solution for pavements.

BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Pervious concrete, also known as porous or permeable concrete, is a specialized type of concrete that allows water to pass through it, rather than accumulating on the surface or running off. Pervious concrete reduces stormwater runoff, which helps prevent flooding and erosion. It allows water to infiltrate into the ground, replenishing groundwater supplies and reducing strain on drainage systems. Despite its benefits, pervious concrete also has some limitations. Kiran et al. [Mater. Sci. Eng., 2018, 310 (1), 012064] observed a strength enhancement in identically gaped pervious concrete with the usage of varied aggregate sizes. Ramkrishnan et al. [Mater. Today. Proc., 2018, 5 (11), 24014–24023] and Hari et al. [J. Build. Eng., 2023, 70, 106307] reported that the addition of mineral admixtures and fibers enhances the performance of pervious concrete. It requires proper maintenance to prevent clogging and maintain its permeability. Regular cleaning and occasional vacuuming may be necessary to remove debris and maintain its functionality.
[0004] Geogrid reinforced pervious concrete is a variation of pervious concrete that incorporates the use of geogrids to enhance its structural performance and load-bearing capacity. Geogrids are synthetic materials typically made from polymer-based materials, such as polyester or polypropylene, that have high tensile strength and are resistant to chemical and biological degradation. Meng X et al. [Constr. Build. Mater., 2019, 215, 275–284] and Ramkrishnan et al. [Civil Infrastructures Confronting Severe Weathers and Climate Changes Conference, Springer, 2018, 144–160] found that the addition of geogrids in pervious concrete helps to distribute and transfer loads more effectively, improving its strength and durability. By incorporating geogrids, the concrete gains additional tensile strength and improved load distribution, allowing it to withstand higher loads without compromising its permeability. Zhang et al. [Constr. Build. Mater, 2019, 211, 12–25; Structures, 2020, 23, 731–738] investigated geogrid-confined pervious geopolymer concrete piles with FRP-PVC-confined concrete and the mechanical behaviour of this new form of piles is significantly improved. Geogrid reinforcement improves pervious concrete’s flexural strength and toughness, enabling it to withstand bending and deformation from applied loads. Geogrids also control crack propagation by adding tensile strength and limiting crack widths, increasing the pavement’s durability and longevity. In a study conducted by Abbas et al. [Constr. Build. Mater., 2017, 146, 165–174], the impact of geogrid placement on the strain of concrete slabs and prisms was investigated. The findings revealed that the placement of geogrids at different depths contributed to a reduction in drying shrinkage and shrinkage strains. For concrete slab specimens, the inclusion of geogrid reinforcement resulted in a shrinkage reduction of 7–28% compared to the control specimens. Additionally, the rate of shrinkage strain was lower when the geogrid was positioned closer to the surface exposed to drying. In their research, Nagy et al. [Procedia Eng., 2017, 181, 472–479] investigated the impact of geogrids on concrete pavements. The triangular geometry enhances stiffness and stability, making it robust under pressure. By including triaxial geogrid ribs, structural bearing capacity increases by 31%, leading to minimal deformation at lower speeds compared to conventional pervious concrete roads.
[0005] SBR (Styrene Butadiene Rubber) is a type of polymer commonly used in the construction industry for various applications, including in the modification of concrete mixtures. Incorporating SBR into pervious concrete can enhance its durability and resistance to factors such as freeze-thaw cycles, abrasion, and chemical exposure. The SBR polymer forms a protective film around the aggregate particles, providing increased strength and reducing the potential for surface deterioration. Bilal et al. [Constr. Build. Mater., 2021, 275, 122124] and Borhan et al. [Case Stud. Constr. Mater., 2020, 12, E00335] found that SBR can improve the compressive and flexural strength of pervious concrete. SBR latex improves mechanical properties, cohesion, and strength by bridging microcracks and enhancing the bond between cement and aggregates. Giustozzi [Constr. Build. Mater., 2016, 111, 502–512] investigated polymer-modified pervious concrete for durable and sustainable transportation infrastructures and found that polymer-modified mixes exhibited enhanced compaction ability, requiring less energy to achieve a specific void content.
[0006] Pervious concrete, designed to be permeable, can clog over time due to accumulated fine particles and debris in its larger void spaces. This reduces permeability, slowing water infiltration and potentially causing ponding or runoff instead of percolation. Elango et al. [Mater. Today, Proc., 2023, 184] did a comparative analysis on clogging effects in pervious concrete. The infiltration rate of larger size aggregate mix is higher compared to smaller size aggregates due to the greater number of pores present in the mix, irrespective of its infiltration properties. Cai et al. [Case Stud. Constr. Mater., 2022, 16, e00864] conducted research on clogging resistance of pervious concrete. Based on the analysis of 2D images, it has been observed that an increased presence of larger pores in pervious concrete can enhance its resistance to clogging. However, the average pore size and tortuosity do not appear to be critical factors affecting clogging resistance. Xuhao Wang et al. [Constr. Build. Mater., 2022, 335, 127455] conducted quantitative assessment of clogging and cleaning effects on the permeability of pervious concrete. Permeability reduction was more significant in specimens with clay silty sand compared to those with sand due to the wider particle size distribution and cohesiveness of clay silty sand. Over 90% of initial permeability was lost after the clogging test, but even with 15% void ratio, fine particles had minimal impact on clogging. Zhang et al. [J. Clean. Prod., 2022, 341, 130878] performed numerical simulation on cleaning of clogged pervious concrete pavement. Research findings on clogging materials’ cleaning efficiency ranked them as follows: coarse sand > well-graded sand > fine sand (which took the longest to clean). Vacuum cleaning is effective for fine particles with deep-reaching action, while pressure washing has limited capacity for deeper pavement layers. Shrinkage in pervious concrete, caused by moisture loss during curing, can significantly impact its performance and durability. Excessive shrinkage leads to cracks, compromising structural integrity and reducing stormwater management effectiveness [Constr. Build. Mater., 2017, 146, 165–174]. Repairing these shrinkage-induced cracks increases costs and disrupts pervious concrete’s intended low-maintenance nature. Abbas et al. [Constr. Build. Mater., 2017, 146, 165–174] investigated the influence of geogrid on the drying shrinkage performance of concrete pavements. They concluded that, apart from the initial drying period of 7–14 days, the utilization of geogrid reinforcement demonstrated a reduction in drying shrinkage strains of the concrete prism specimens, exceeding the reference by approximately 0.7% to 15%.
[0007] Literature reported the individual contributions of both SBR and geogrid applications in pervious concrete. Geogrid-reinforced pervious concrete can face clogging from accumulated fine particles and debris. However, limited studies exist on geogrid’s impact on strength and clogging characteristics.
[0008] Thus, there is a need to develop a novel pervious concrete which have better mechanical properties.

OBJECTIVES OF THE INVENTION
[0009] An objective of the present disclosure is to provide a styrene butadiene rubber modified pervious concrete reinforced with geogrid.
[00010] Another objective of the present disclosure is to provide a method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid.
[00011] Still another objective of the present disclosure is to provide a novel pervious concrete having improved mechanical properties.

SUMMARY OF THE INVENTION
[00012] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in Detailed Description section. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
[00013] The present disclosure relates to a field of construction materials and pavement engineering. Particularly, the present disclosure relates to a styrene butadiene rubber modified pervious concrete reinforced with geogrid. The present disclosure also provides a method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid. The present disclosure provides better mechanical properties and can be a promising solution for pavements.
[00014] An aspect of the present disclosure provides a styrene butadiene rubber modified pervious concrete reinforced with geogrid comprising: i) a styrene butadiene rubber modified pervious concrete comprising: a cement; coarse aggregates; styrene butadiene rubber; and water; and ii) a geogrid.
[00015] Another aspect of the present disclosure provides a method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid comprising: a) mixing of coarse aggregates and cement under condition to obtain a mixture I; b) adding half part of the water in the mixture of step a) with continuous mixing to obtain a mixture II; c) adding remaining half water to the styrene butadiene rubber to obtain a mixture III; d) adding the mixture III of step c) to the mixture II of step b) under condition to obtain a styrene butadiene rubber modified pervious concrete; e) transferring the styrene butadiene rubber modified pervious concrete in a mould containing a geogrid with uniform tamping to obtain a specimens; and f) curing the specimens under condition to obtain a styrene butadiene rubber modified pervious concrete reinforced with geogrid.
[00016] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the exemplary embodiments of the invention.

DESCRIPTION OF THE FIGURES
[00017] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[00018] FIG. 1 illustrates meshes or grids employed for the study (a) glass fiber mesh, (b) HDPE fencing mesh, (c) polyester geogrid, (d) HDPE geogrid, (e) fibre glass geogrid and (f) coir geogrid.
[00019] FIG. 2 illustrates load deflection characteristics of the grids.
[00020] FIG. 3 illustrates specimen preparation for flexural loading (a) schematic diagram of flexural test specimen, (b) actual specimens cast, and the mould used.
[00021] FIG. 4 illustrates specimen preparation for shrinkage test (a) mould for shrinkage test, (b) panel specimen for shrinkage test.
[00022] FIG. 5 illustrates FDA – Step by step process.
[00023] FIG. 6 illustrates functional plot of permeability characteristics for different SBR content.
[00024] FIG. 7 illustrates derivative plot of permeability vs SBR content.
[00025] FIG. 8 illustrates p value plot of permeability.
[00026] FIG. 9 illustrates schematic diagram representing assembly for measuring biaxial shrinkage (1) dial gauge to measure shrinkage along y direction, (2) rigid frame, (3) pervious concrete panel, (4) dial gauge to measure shrinkage along x direction, (5) gripping assembly and (6) rigid base plate.
[00027] FIG. 10 illustrates heatmap of biaxial Shrinkage strain of grid/mesh reinforced pervious concrete (a) shrinkage strain (x10-5) in X direction-control mix, (b) shrinkage strain (x10-5) in Y direction-control mix, (c) shrinkage strain (x10-5) in X direction-glass fibre mesh, (d) shrinkage strain (x10-5) in Y direction-glass fibre mesh, (e) shrinkage strain (x10-5) in X direction-HDPE mesh, (f) shrinkage strain (x10-5) in Y direction- HDPE mesh, (g) shrinkage strain (x10-5) in X direction-fibre glass geogrid, (h) shrinkage strain (x10-5) in Y direction-fibre glass geogrid, (i) shrinkage strain (x10-5) in X direction-HDPE geogrid, (j) shrinkage strain (x10-5) in Y direction-HDPE geogrid, (k) shrinkage strain (x10-5) in X direction-polyester geogrid, (l) shrinkage strain (x10-5) in Y direction-polyester geogrid, (m) shrinkage strain (x10-5) in X direction-coir-geogrid and (n) shrinkage strain (x10-5) in Y direction-coir-geogrid.
[00028] FIG. 11 illustrates centre point loading assembly for flexural strength test.
[00029] FIG. 12 illustrates functional Plot of flexural strength characteristics for different SBR content.
[00030] FIG. 13 illustrates derivative plot of flexural strength characteristics for different SBR content.
[00031] FIG. 14 illustrates p-value plot of flexural strength characteristics for different SBR content.
[00032] FIG. 15 illustrates characterization of turbid water (a) hydrometer analysis and (b) Imhoff cone test.
[00033] FIG. 16 illustrates particle size distribution of soil particles by hydrometer analysis.
[00034] FIG. 17 illustrates volume of settleable solids with time.
[00035] FIG. 18 illustrates clogging characteristics.
[00036] FIG.19 illustrates soil accumulation on the surface of specimen after clogging test.
[00037] FIG. 20 illustrates derivative plot of clogging.
[00038] FIG. 21 illustrates p-value plot for clogging.

DETAILED DESCRIPTION OF THE INVENTION
[00039] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered 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 spirit and scope of the present disclosure as defined by the appended claims.
[00040] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[00041] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[00042] In some embodiments, numbers have been used for quantifying weights, percentages, ratios, and so forth, to describe and claim certain embodiments of the invention and are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable.
[00043] The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[00044] Unless the context requires otherwise, throughout the specification which follows, the word “comprise” and variations thereof, such as “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”
[00045] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[00046] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. Furthermore, the ranges defined throughout the specification include the end values as well, i.e., a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, the applicant shall be entitled to any equivalents according to applicable law.
[00047] All methods described herein can be performed in a suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[00048] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified.
[00049] The description that follows, and the embodiments described therein, is provided by way of illustration of an example, or examples, of particular embodiments of the principles and aspects of the present disclosure. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the disclosure.
[00050] It should also be appreciated that the present disclosure can be implemented in numerous ways, including as a system, a method or a device. In this specification, these implementations, or any other form that the invention may take, may be referred to as processes. In general, the order of the steps of the disclosed processes may be altered within the scope of the invention.
[00051] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[00052] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[00053] The term “or”, as used herein, is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
[00054] Various terms are used herein to the extent a term used is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[00055] An embodiment of the present disclosure provides a styrene butadiene rubber modified pervious concrete reinforced with geogrid comprising: i) a styrene butadiene rubber modified pervious concrete comprising: a cement; coarse aggregates; styrene butadiene rubber; and water; and ii) a geogrid.
[00056] In an embodiment, the cement has an amount in the range of 200 to 600 kg/m3. Preferably, the cement has an amount in the range of 300 to 500 kg/m3. More preferably, the cement has an amount of 400 kg/m3.
[00057] In an embodiment, the coarse aggregates have an amount in the range of 1300 to 1700 kg/m3. Preferably, the coarse aggregates have an amount in the range of 1400 to 1600 kg/m3. More preferably, the coarse aggregates have an amount of 1485 kg/m3.
[00058] In an embodiment, the water has an amount in the range of 120 to 160 kg/m3. Preferably, the water has an amount in the range of 130 to 150 kg/m3. More preferably, the water has an amount of 140 kg/m3.
[00059] In an embodiment, the styrene butadiene rubber has an amount in the range of 0% to 15% by weight of cement. Preferably, the styrene butadiene rubber has an amount in the range of 1% to 15% or 2% to 15% or 3% to 15% or 4% to 15% or 5% to 15% by weight of cement.
[00060] In an embodiment, the geogrid is selected from a group consisting of Glass fiber mesh, HDPE mesh, fiber glass geogrid, HDPE geogrid, coir geogrid and combination thereof.
[00061] Another embodiment of the present disclosure is to provide a method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid comprising: a) mixing of coarse aggregates and cement under condition to obtain a mixture I; b) adding half part of the water in the mixture of step a) with continuous mixing to obtain a mixture II; c) adding remaining half water to the styrene butadiene rubber to obtain a mixture III; d) adding the mixture III of step c) to the mixture II of step b) under condition to obtain a styrene butadiene rubber modified pervious concrete; e) transferring the styrene butadiene rubber modified pervious concrete in a mould containing a geogrid with uniform tamping to obtain a specimens; and f) curing the specimens under condition to obtain a styrene butadiene rubber modified pervious concrete reinforced with geogrid.
[00062] In an embodiment, the dry mixing is carried out in step a) for a period in the range of 1 to 5 min. Preferably, the dry mixing is carried out in step a) for a period in the range of 2 to 4 min. More preferably, the dry mixing is carried out in step a) for a period of 3 min.
[00063] In an embodiment, the mixing in step d) is carried out for a period in the range of 1 to 5 min till uniform consistency is obtained. Preferably, the mixing in step d) is carried out for a period in the range of 2 to 4 min till uniform consistency is obtained. More preferably, the mixing in step d) is carried out for a period of 3 min till uniform consistency is obtained.
[00064] In an embodiment, the curing in step f) is carried out by water immersion method for a period in the range of 25 to 30 days. Preferably, the curing in step f) is carried out by water immersion method for a period in the range of 26 to 29 days, more preferably, the time period is in the range of 27 to 29 days, most preferably, the time period is 28 days.
[00065] Pervious concrete is a specialized form of concrete characterized by its high porosity and limited structural strength. Geogrid reinforced pervious concrete represents a variant that integrates geogrids to enhance its structural performance. This composite material leverages the tensile strength and load distribution capabilities of geogrids, thereby improving overall structural integrity. The present disclosure focuses on evaluating the mechanical properties, shrinkage behavior, and susceptibility to clogging of pervious concrete modified with Styrene Butadiene Rubber (SBR) and reinforced with various types of grids and meshes including glass fiber mesh, HDPE mesh, fiber glass geogrid, HDPE geogrid, and coir geogrid. SBR modification ranges from 0% to 15% by weight of cement. Results indicate a significant enhancement in flexural strength with SBR modification, with HDPE geogrid demonstrating nearly double the flexural strength compared to non-reinforced pervious concrete. Additionally, SBR modification contributes to improved mechanical properties, with each grid/mesh exhibiting an optimal SBR dosage for maximal flexural strength. Furthermore, the incorporation of geogrids mitigates drying shrinkage in pervious concrete, with the relative contact area between the grid/mesh and cement paste playing a crucial role in reducing shrinkage. However, geogrids also pose a risk of clogging, as soil particles accumulate within the void spaces, diminishing permeability. Coir geogrid exhibits a higher propensity for soil particle retention, further impairing permeability. Functional regression modeling utilizing Functional Data Analysis is employed to analyze the intricate relationship between different grid and mesh types and the properties of pervious concrete. Through p-value and derivative plots, a deeper understanding of factorial effects is achieved, providing valuable insights for optimizing the performance of pervious concrete systems.
[00066] SBR Polymer modified pervious concrete incorporated with geogrids show the following characteristics:
• Improved flexural strength and each geogrid has its own dosage of SBR polymer for best results.
• HDPE geogrid shows the maximum flexural strength.
• Fibre glass geogrid resulted in remarkable reduction in drying shrinkage.
• More clogging is observed for pervious concrete with coir geogrid by trapping more soil particles.
[00067] Hence the SBR polymer modified pervious concrete incorporated with geogrids exhibit better mechanical properties and can be a promising solution for pavements.
[00068] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
EXAMPLES
[00069] The present invention is further explained in the form of the following examples. However, it is to be understood that the following examples are merely illustrative and are not to be taken as limitations upon the scope of the invention.
Example 1: Method of preparation of styrene butadiene rubber modified pervious concrete reinforced with geogrid
(A) Strength characterization of grids/mesh
[00070] FIG. 1 (a) to (f) shows the various meshes/grids used in the study. Tensile load test was conducted on all the grids/meshes as per IS 13325. The grids/meshes were gripped to the loading head of a UTM by a jig plate assembly. The tensile load was applied without shock and the elongation was measured at various loading intervals till failure. Load deflection curve was plotted to assess the relative strength and ductility of the grids/meshes. FIG. 2 shows the load deflection characteristics of the grids/meshes.
(B) Material properties
[00071] Table 1 shows the properties of bulk materials used for the study.
Table 1: Properties of materials used.
Material Property Test Result Test Reference
Cement Specific Gravity
Normal Consistency
Initial Setting Time
Final Setting Time 2.91
35%
120 min
255 min IS 4031 – Part 11
IS 4031 – Part 4
IS 4031 – Part 5
IS 4031 – Part 5
Coarse
Aggregate Specific Gravity
Water Absorption % Voids in CA matrix
10mm-12.5 mm 2.65
1.1%
51.2 IS 4031 – Part 3
IS 4031 – Part 3
ASTM C29/C29M-97

(C) Alkali treatment of coir geogrid
[00072] The alkali treatment of coir was carried out for improving the fibre’s strength, flexibility, and compatibility with different materials. It helps to remove organic polymers, such as lignin and pectin, from the coir fibres, resulting in cleaner and more refined fibres. Alkali treatment also alters the surface chemistry of the coir fibres. It increases the fibre’s hydrophilicity, making it more receptive to water-based treatments, coatings, or adhesives. Coir geogrid was treated with 4% NaOH solution. Geogrid was immersed in NaOH solution for 24 h. It was then taken out, washed in acetic acid and then in water and kept for drying. Tensile load testing was done in treated coir geogrid.
(D) Mix proportions
[00073] The Pervious concrete mix proportion was done as per IRC 44 – 2017. Table 2 shows the details of control mix.
Table 2: Control mix details.
Material Quantity
Cement 400 kg/m3
Coarse aggregate 1485 kg/m3
Water 140 kg/m3

(E) Mix combinations
[00074] 28 mix combinations were achieved by adjusting the quantities of SBR within the weight intervals of 0%, 5%, 10%, and 15% relative to the cement weight. These mixtures were reinforced using six different grids/meshes. The various mix combinations include control mix, control mix with combinations of glass mesh, HDPE mesh, fiber glass mesh, polyester geogrid, coir geogrid, and each with 5%, 10% and 15% SBR.
(F) Mixing, casting and specimen preparations
[00075] The mixing of ingredients of pervious concrete was done in a pan mixer. Weigh batched coarse aggregate, and cement was added to the mixer and dry mixing was carried out for 3 min. Half part of the required water was then added to the mixer and continued mixing. The remaining water was mixed with weighed quantity of SBR and added to the mixer. The mixture was then mixed for 3 mins till uniform consistency was obtained. The mixture of SBR modified pervious concrete was then transferred to the moulds prepared with uniform tamping. Care was taken so that the position of the mesh /grid was not disturbed. The specimens were cured by water immersion method for 28 days.
[00076] Specially fabricated mould was used for preparing flexural strength test specimens. The mould assembly consists of two parts which are detachable. Such an assembly is made to ensure the horizontality of the grid or mesh in the specimen, which may otherwise get dislocated by compaction. The grids/meshes were placed at d/4 from the bottom face of the beam specimen where d is the depth of the beam. The specimens are cast inverted. The 75 mm wide part was placed at the bottom and the concrete was filled in layers with tamping. The grid/mesh was placed over it with sufficient length projecting outside to get better grip and not getting displaced during tamping. Then the 25 mm wide part of the mould was placed on it and fixed in place. The remaining portion was then filled with concrete. FIG. 3(a) shows the schematic of laying grid/mesh in the beam specimen. FIG. 3(b) shows the fabricated mould and specimens cast for flexural loading. Shrinkage specimens are also made in two parts as like flexural test specimens. Two parts of size 25 mm × 380 mm × 380 mm of the whole mould were placed one over other with a layer of grid/mesh in between, and then used as shrinkage test specimen as shown in FIG. 4 (a) and (b).
[00077] Cylindrical specimens of 100 mm in height and diameter are used for permeability and clogging characteristics. The modification by SBR has not been performed on the specimen for clogging characteristics as trial experiments with SBR modification did not significantly impact the clogging characteristics. Functional Data Analysis (FDA) is a statistical approach used to analyse and interpret data that are observed as functions or curves rather than single values or vectors. The process of FDA involves several steps as shown in FIG. 5
Example 2: Characterization
(A) Permeability characteristics
[00078] Permeability or infiltration rate test was carried out with a falling head arrangement. The test was carried out with reference to ISO 17785–1:2016.
[00079] FIG. 6 shows the functional plot permeability characteristics of the grid/mesh reinforced pervious concrete for various SBR percentages. Red dot on a curve indicates the mean observed value of permeability of that grid/mesh reinforced pervious concrete. Figure shows that there is a reduction in the permeability of mixes as the SBR percentage increases. The addition of SBR to pervious concrete readily leads to a reduction in pore spaces and thereby reduction in permeability coefficient. Coir geogrid shows the largest permeability coefficient among all the grids/meshes. The coir grid being woven can create more void spaces than other grids/meshes. However, it shows an abrupt reduction in permeability after 10% of SBR. This may be due to the accumulation of SBR particles in between the coir fibres and the reduction of pore size. Visual observation on broken test specimens indicated the sticking of dry SBR –cement paste between woven coir fibres. Reinforcing the pervious concrete with geogrid/mesh can reduce the permeability. Fiber glass geogrid and glass fibre mesh yielded the least permeability which may be due to its lower opening size and formation of cement paste films across the smaller openings.
[00080] The functional plot of permeability indicates a gradual drop in permeability with increase in SBR content. However, the rate of decrease in permeability is different for each fibre and is evident from the derivative plot as shown in Fig. 7. Each of the curves indicate that the reduction in permeability is prominent beyond 5% addition of SBR. Also, coir geogrid shows the maximum decline in permeability with the addition of SBR. Fig. 8 indicates the p value function plot for fANOVA. It shows that p value < 0.05 for all the grids or meshes vis-`a-vis control mix for all values of SBR which statistically means that permeability of pervious concrete reduces with increase in SBR content and changes for different grids/meshes.
(B) Shrinkage characteristics
[00081] The pervious concrete panel specimen measuring 50 mm × 380 mm × 380 mm as shown in FIG. 4 (b) undergoes curing for 7 days by immersion method before being retrieved for testing. Dial gauges were employed to measure and record the length variations in both the x and y directions. The measurement process was continued for 28 days at an interval of 7 days. FIG. 9 shows the assembly of measuring shrinkage strain in both directions.
[00082] By representing data values as colours, heatmaps make it easier to perceive variations and understand the underlying structure of the response. Heatmap of the biaxial shrinkage strain of the mixes are shown in FIG. 10 (a) to (n). Shrinkage reduces with increase in the curing age. Increase in SBR content reduces the shrinkage of pervious concrete. Laying a layer of mesh/grid can also reduce the shrinkage. Fiber glass geogrid yields the least shrinkage in pervious concrete for any SBR dosage. The contact area of a grid/mesh with cement paste in pervious concrete has been identified as a crucial factor in influencing shrinkage rather than its tensile strength. The difference in contact area of the grids/meshes is due to the difference in the size of openings and thickness of the ribs. HDPE geogrid having the largest tensile strength among the grids/meshes could not yield a lesser shrinkage. However, coir geogrids have a negative effect. Coir geogrid increased the shrinkage of pervious concrete. The phenomenon may be due to the autogenous shrinkage of coir fibres on drying and thereby adding to the total shrinkage of pervious concrete. Polyester geogrid having different tensile strength in biaxial direction also yields different shrinkage in the corresponding directions.
(C) Flexural strength characteristics
[00083] Centre point loading is used to carry out flexural strength test. Beam specimens of size 100 mm × 100 mm × 500 mm was used. FIG. 11 shows the assembly of flexural load testing.
[00084] FIG. 12 shows the functional plot of flexural strength with respect to different percentages of SBR. Red dot on a curve indicates the mean observed value of flexural strength of that grid/mesh reinforced pervious concrete. It was observed that each grid/mesh had its own optimum value of SBR content for which the mix yielded the maximum flexural strength value. Also, a very large dosage of SBR did not yield better results. This may be because pervious concrete has a different matrix structure vis-`a-vis normal concrete. Pervious concrete has a hollow structure with lesser cement paste which cannot be enriched with more quantity of SBR. The reason could possibly be the gripping and stress transfer occurring between the SBR matrix and the grid/mesh. Reinforcing the pervious concrete with geogrids/meshes can enhance the flexural strength characteristics. For non SBR modified mixes, it is observed that HDPE geogrid has the largest flexural strength and glass fibre mesh the lowest. Also, coir geogrid reinforced mixes yield better flexural strength at lower SBR percentages. The larger quantity of SBR may be hindering the grip between woven fibres of coir geogrid. Failure of flexure specimens is found to be more ductile. Polyester geogrid, HDPE geogrid and coir geogrid because of its ductile nature which is evident from FIG. 2 contributed towards the yielding and ductile failure.
[00085] FIG. 13 shows the derivative plot of flexural strength characteristics of geogrid / mesh reinforced SBR modified pervious concrete. FIG. 13 clearly shows that each grid / mesh has its own optimum value of SBR dosage. The point at which the derivative plot cuts the zero axis indicates the percentage of SBR where the maximum flexural strength is achieved. However, HDPE mesh does not cut the zero line which probably indicates a percentage of SBR beyond 15%. The p-value plot as shown in FIG. 14 indicates the effective dosage of SBR content for a particular grid/mesh which contributes towards flexural strength enhancement of pervious concrete vis-`a-vis control mix. The corresponding values of SBR percentage where the curves fall below the p = 0.05 line show the statistically significant amount of SBR required to enhance the flexural strength. Fibre glass mesh shows an enhancement in flexural strength vis-`a-vis control mix for SBR > 5%. However, HDPE mesh enhances the flexural strength for SBR < 5%. Similarly, coir geogrid is effective for SBR < 10% (approx.). Pervious concrete reinforced with fibre glass geogrid, HDPE geogrid and polyester geogrid contributes towards flexural strength enhancement irrespective of the amount of SBR added. However, the optimum dosage may be obtained considering the corresponding derivative plot along with p-value plot.
(D) Clogging characteristics
[00086] The clogging rate of pervious concrete refers to the speed at which void spaces inside the material become filled or obstructed by small particles, debris, or other substances. It serves as an indicator of the permeability reduction caused by clogging. The clogging rate can fluctuate depending on multiple factors such as soil composition, the quantity and nature of pollutants encountered by the pervious concrete, maintenance procedures, and environmental conditions. Soil characterization was performed to assess the properties of the soil used for the study. In the present disclosure, soil passing through 1.18 mm was used. Hydrometer analysis was performed as per IS 2720 – Part IV to assess the relative particle size of soil present in the turbid water as shown in FIG. 15(a). The turbid water was allowed to settle in an Imhoff cone to assess the volume of settleable solids at different intervals of time as shown in FIG. 15(b). The results are shown in FIGs. 16 and 17 respectively. FIG. 16 indicates that the soil particles are in the range of silt which contributes towards clogging of void spaces. Soil particle settlement can be categorized as primary and secondary. Primary settlement happens when the turbid water flows through the pervious concrete. FIG. 17 indicates that a major volume of soil particles gets settled within no time which is termed as primary settlement. Hence, the soil particles chosen for the clogging characteristics study can settle in the concrete void spaces during the flow of water through the pervious concrete. Secondary settlement indicates the settlement occurring inside the pore spaces when the turbid water gets trapped inside the pervious concrete when no flow occurs. Only a smaller quantity settles as a part of the secondary settlement. The natural phenomenon of clogging is simulated by allowing the known volume of turbid water of known solid content to pass for several cycles through a cylindrical specimen of 100 mm height and diameter.
[00087] In the present disclosure, one clogging cycle is defined as passing of 1 L of water containing 10 g of soil through a cylindrical specimen of size 100 mm height and 100 mm diameter. The clogging rate is found by measuring the loss in permeability after regular clogging intervals. A small amount of SBR is added to the turbid water so that the settled soil particles in the void spaces gets hard and not been washed away due to successive cycles of clogging, to simulate actual field conditions.
[00088] FIG. 18 shows the functional plot of clogging characteristics of the grid/mesh reinforced pervious concrete. The investigation was conducted only on non-SBR modified mixes. With an increasing number of clogging cycles, a significant decrease in permeability is observed. The percentage loss in permeability is found more for grid/mesh reinforced mixes. Reinforcing the concrete with grids/meshes can trap more amount of soil particles and thereby reduce the permeability. Coir geogrid shows the maximum clogging and reduction in permeability for a particular number of clogging cycles. The woven structure of coir grid traps a larger quantity of soil particles and clogs the pores. HDPE geogrid shows the least percentage reduction in permeability. However, it is observed that, as the number of cycles increases all the grid/mesh reinforced mixes show similar clogging characteristics. This is due to the reason that, the soil particles get accumulated on the surface of the specimen and arrest the flow. FIG. 19 (a) and (b) shows the accumulation of soil particles on the surface of the specimen on the last stage of clogging test.
[00089] FIG. 20 shows the derivative plot of clogging percentage. It indicates the rate of clogging of pervious concrete when different meshes/grids are used. The rate of clogging increases and reduces beyond a certain number of clogging cycles. It means that initially the clogging happens due to the hindrance caused by the grids/meshes. However, after a certain number of cycles the clogging is mainly due to the accumulation of soil particles on the top surface of specimen. This phenomenon is clearly observed in the p-value plot shown in FIG. 21. The p-value is greater than 0.05 for all the grids/meshes beyond a certain value of clogging cycle. This clogging cycle number represents the point at which a grid/mesh-reinforced pervious concrete begins to accumulate soil particles on its surface. This may be used to plan the periodic cleaning of pervious concrete pavements to remove the surface accumulation and regain the permeability of the pavement. Some of the possible techniques include vacuum sweeping, pressure washing and mechanical scrubbing.
[00090] The foregoing examples are merely illustrative and are not to be taken as limitations upon the scope of the invention. Various changes and modifications to the disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the scope of the invention.

ADVANTAGES OF THE PRESENT INVENTION
[00091] The present disclosure investigates the mechanical, shrinkage and clogging characteristics of Styrene Butadiene Rubber (SBR) modified pervious concrete reinforced with various grids/meshes. Laying of meshes/grids enhances the flexural strength characteristics of the pervious concrete. SBR modifications can also enhance the strength and reduce shrinkage.
[00092] Each tested grid/mesh displayed its unique optimum dosage of SBR (Styrene Butadiene Rubber) for achieving maximum flexural strength in pervious concrete.
[00093] The HDPE (High-Density Polyethylene) geogrid exhibited the highest flexural strength, indicating that a more enriched mix can be employed to fully harness the superior strength properties of HDPE geogrid.
[00094] The fibre glass geogrid demonstrated a remarkable reduction in drying shrinkage, indicating its potential for mitigating shrinkage related issues in pervious concrete.
[00095] The extent of contact area between the geogrid layer and the cement paste in pervious concrete emerged as a significant factor influencing drying shrinkage reduction.
, Claims:1. A styrene butadiene rubber modified pervious concrete reinforced with geogrid, comprising:
i) a styrene butadiene rubber modified pervious concrete comprising:
cement;
coarse aggregates;
styrene butadiene rubber; and
water; and
ii) a geogrid.
2. The modified pervious concrete as claimed in claim 1, wherein the cement has an amount in the range of 200 to 600 kg/m3.

3. The modified pervious concrete as claimed in claim 1, wherein the coarse aggregates have an amount in the range of 1300 to 1700 kg/m3.

4. The modified pervious concrete as claimed in claim 1, wherein the water has an amount in the range of 120 to 160 kg/m3.

5. The modified pervious concrete as claimed in claim 1, wherein the styrene butadiene rubber has an amount in the range of 0% to 15% by weight of cement.

6. The modified pervious concrete as claimed in claim 1, wherein the geogrid is selected from a group consisting of Glass fiber mesh, HDPE mesh, fiber glass geogrid, HDPE geogrid, coir geogrid and combination thereof.

7. A method of preparation of a styrene butadiene rubber modified pervious concrete reinforced with geogrid comprising:
a) mixing of coarse aggregates and cement under condition to obtain a mixture I;
b) adding half part of the water in the mixture of step a) with continuous mixing to obtain a mixture II;
c) adding remaining half water to the styrene butadiene rubber to obtain a mixture III;
d) adding the mixture III of step c) to the mixture II of step b) under condition to obtain a styrene butadiene rubber modified pervious concrete;
e) transferring the styrene butadiene rubber modified pervious concrete in a mould containing a geogrid with uniform tamping to obtain a specimens; and
f) curing the specimens under condition to obtain a styrene butadiene rubber modified pervious concrete reinforced with geogrid.

8. The method as claimed in claim 7, wherein the dry mixing is carried out in step a) for a period in the range of 1 to 5 min.

9. The method as claimed in claim 7, wherein the mixing in step d) is carried out for a period in the range of 1 to 5 min till uniform consistency is obtained.

10. The method as claimed in claim 7, wherein the curing in step f) is carried out by water immersion method for a period in the range of 25 to 30 days.