COMPRATIVE STUDY OF REINFORCED SOIL OF BIDAR DIRSTIC WITH GEOGRID-1, GEOGRID-2 & GEO-MEMBRANE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 9, September 2017, pp , Article ID: IJCIET_08_09_009 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed COMPRATIVE STUDY OF REINFORCED SOIL OF BIDAR DIRSTIC WITH GEOGRID-1, GEOGRID-2 & GEO-MEMBRANE N. Vijay Kumar Research Scholar, Department of Civil Engineering, K L University, Vaddeswaram, Guntur, Andhra Pradesh, India SS. Asadi Associate Dean Academics & Professor, Department of Civil Engineering, K L University, Vaddeswaram, Guntur, Andhra Pradesh, India A.V.S. Prasad Professor, Department of Civil Engineering, K L University, Vaddeswaram, Guntur, Andhra Pradesh, India ABSTRACT Road pavements are vulnerable (weak) to soil performance because the foundation of the pavement sub-grade soil is most important element. And if the sub-grade layer of pavement consists of Black cotton soil and lateritic soil, due to changes in moisture content and subsequent shrinkage and swelling, it undergoes failure. Thus, for the construction on such type of soil it is required to improve the engineering properties of soil or to replace the soil itself. Replacing the existing soil might not be a practical and feasible option, thus it is required to stabilize the soil with suitable stabilizer. However the selection of stabilizer depends upon the type of sub-grade soil, type of soil improvement desired, availability of stabilizer, the required strength and durability of stabilized layer, various stabilizing techniques, environmental conditions and the most important cost factor. This paper reviews the work of various researchers on stabilization of soil and use of geo-synthetic materials in improving its strength. Keywords: BC soil, Particle size Distribution, shear strength, California bearing ratio, Compressibility. Cite this Article: N. Vijay Kumar, SS. Asadi and A.V.S. Prasad, Comprative Study of Reinforced Soil of Bidar Dirstic With Geogrid-1, Geogrid-2 & Geo-Membrane, International Journal of Civil Engineering and Technology, 8(9), 2017, pp editor@iaeme.com

2 N. Vijay Kumar, SS. Asadi and A.V.S. Prasad 1. INTRODUCTION Maintenance and development is the major issue in the pavement infrastructure. In General practices, higher quality of materials are to satisfy standards in the permanent pavement Construction and sub-grade soil doesn t satisfy in many regions in the world. It requires alternative Solution for the use of weaker sub grade soil. The load is transferred from the pavement toward the second stratum of soil which should have enough strength. This can be achieved by using Geo-synthetics in terms of Geogrids & Geomembrane which are capable to increases the strength at the sub grade sail. Geogrids are mainly used as reinforcement materials in the structures like embankments, retaining walls, slopes and pavements etc. can be placed in between base coarse and sub base coarse. Many researchers have suggested that by inclusion of Geogrids between the base coarse and sub base coarse will significantly increase the performance of the pavement. It has been observed in both field and laboratory experiments. Their studies have shown that there was increase in CBR values for both unasked & soaked conditions using reinforcement in the soils. 2. OBJECTIVES The Prime Aim of the Present Investigation Is to Assess the Usefulness of Geo-grid and Geomembrane As Soil Reinforcement. The present investigation has been limited to the following studies. 1. To Study the Comparison of Road pavements Constructed With Geo-grid and Geomembrane. 2. To Study The Strengthening Of Soil Of Low BearingCapacity. 3. To Study The Effect Of Geotextile As An Arrests MigratingOf Soil Particle And Allows Water To Permeate Across It. 4. To Study the Influence of Geo-grid and Geo-membrane On California bearing ratio. 3. MATERIALS USED 3.1. Here mainly five materials were used, namely 1. Lateritic and Black cotton soil. 2. Geogread.1 3. Geogread.2 4. Geo-membrane Collection of lateritic soil. Lateritic soil was collected from Shivanagar area of Bidar District in Karnataka State. The sample was collected from depth of 0.8m from ground level with the help of crow bars and powdy. Bigger size lumps were broken down with the help of pick axed and rammer. The soil was pulverized with wooden mallet then air dried Collection of black cotton soil. Black cotton soil was collected from cross road of Bhalki taluk, Bidar district in Karnataka state as was used for this study. The sample was collected manually from depth of0.9m with the help of crow bars and powdy. Bigger size lumps are broken down with the help of pick axed and rammer. The soil was pulverized with wooden mallet then air dried editor@iaeme.com

3 Comprative Study of Reinforced Soil of Bidar Dirstic With Geogrid-1, Geogrid-2 & Geo-Membrane 3.2. Geogrid-1. Figure 1 Sample of Geogrid Physical properties: Many of the physical property of Geogrids can be calculated directly & relatively straight forwards. it contain the type of arrangement, connection type, opening size and width. Additional property that are of interest are density, mass per unit area etc. Aperture size is the 25.4mm, thickness is 2mm, density will be 0.897g/cm3 & 0.066g/cm2 is the mass per unit area of the Geogread Chemical properties: Polyolefin Polypropylene, polyethylene & polyesters used in Geogrids have elevated Exceptional resistance to a broad collection of chemicals Geogrids Figure 1 Sample of Geogrid-1 Figure 2 Sample of Geogrid Physical properties: This is woven by high tenacity, multifilament polyester yarns and coated with durable Polymer which can provide the best resistance of UV and durability. Advantage is high tensile modulus and low creep behavior.etc. successfully offers the stability to earth structures, such as reinforced retaining wall or steep slope, road, bridge or pavement construction. Tensile strength is 2053lb/ft, elongation 10%, and long term design strength 1214 lb/ft Chemical properties: Polyolefin Polypropylene, polyethylene and polyesters used in Geogrids have high excellent resistance to a wide range of chemicals editor@iaeme.com

4 N. Vijay Kumar, SS. Asadi and A.V.S. Prasad Geo-membrane. Figure 3 Sample of Geo-membrane Physical properties: Thickness -500 micron, density-0.94 g/cm3, mass per unit area 6.4 kg/m2, uv radiation-2%, compressive strength-2200 mpa, type -HDPE virgin, color-black Chemical properties: HDPE-35%,LLDPE-25%,PVC-25%,Flexiblepolypropylene- 10%,chlorosulfonatedpolyethylene-2%, ethylenepropylenedine+polymer-3% METHODOLOGY Preparation of samples. Specimen for testing the CBR has done by taking the soil mass of about 4.5 kg, which was passed through a sieve of size 20mm. OMC which we had gotten from standard proctor test will added in the soil mass and mixed thoroughly until lumps vanishes. keep the CBR mould ready by fixing it to base plate and spacer disc of size 3,7cm will be placed at the bottom of the mould, after being mixed the soil mass is poured in CBR mould which is having a size of diameter 15cm and height of 17.5cm and it will compacted in three layers by giving 25 blows for each layer for light compaction. After compacting the second layer collar will be placed and compacting third layer is carried out and for the compacting the 3rd layer the collar will be removed and the extra part of soil mass is trimmed until it gets to smooth surface. Reinforcement is done at certain depth from top of the specimen. Index properties on the BC soil were carried out in accordance with the procedure outlined in IS 2720, step different types of geosynthetic materials introduced into the soil The following tests were carried out on the natural BC soil: Natural moisture content, Specific gravity, Grain size analysis, Atterberg s limits. Compaction test, California Bearing Ratio Test. A. Geotechnical properties (Results of tests carried out in natural BC soil are summarized Table 1) S.NO Parameters Lateritic soil Black cotton soil 1 Specific gravity Gs Atterberg s limits % Liquid limit Plastic limit Plasticity index Sieve analysis% Sand Silt Clay editor@iaeme.com

5 Comprative Study of Reinforced Soil of Bidar Dirstic With Geogrid-1, Geogrid-2 & Geo-Membrane Effective particle size (D10) mm (D30)mm (D60)mm Coefficient of uniformity (Cu) Coefficient of curvature (Cc) Optimum moisture content Maximum dry density kn/m IS classification CH CH&MH Table 1 Geotechnical Properties of the Untreated Black Cotton Soil. B. Atterberg s Limits Liquid limit = 44.5 Plastic limit = 35.3 Plasticity index = 9.2 Plasticity index of BC and laterite soils 9.2% and 15%. So according to unified soil classification system (USCS) clay is classified as inorganic clays of high compressibility (CH) and (CH&MH) C. Compaction Test (Standard Proctor test). Fig 4 shows the relation between water content and dry density. The optimum moisture content of block cotton soil has been found Wo = 24% and max.dry density has been found % Figure 1 Graph for sieve analysis of Black cotton soil The above graph shows sieve analysis test of BC soil content sand is 30.5%, silt is 44.37% and 24.5% of clayey content. Figure 2 Graph for Sieve Analysis of Lateritic soil editor@iaeme.com

6 N. Vijay Kumar, SS. Asadi and A.V.S. Prasad The above graph shows sieve analysis test of lateritic soil content sand is 40%, silt is 25.5%&clay content is 34.8%. Figure 3 Graph for compaction test of BC soil. Above graph shows the compaction test of BC soil is 24% of Optimum moisture content &15.901% maximum dry density. Figure 4 Graph for compaction test for lateritic soil. The above graph shows the compaction test of lateritic soil is 12% is Optimum moisture content and % maximum dry density. 5. RESULTS AND DISCUSSIONS For this project the samples are prepared for following proportions. 1. Geogrid-1, Geogrid-2, & Geomembrane are the reinforcement which is placed at different depths from the top of the CBR mould at 4cm, 8cm &12cm for both lateritic soil as well as Black cotton soil. The test is conducted single layer reinforcement as in 4cm depth, 8cm depth &12cm depth. And in multi-layer reinforcement two layers will be reinforced with a depth of 8cm and 12cm and other one will be the 4cm, 8cm and 12cm depth. The soil will be reinforced with the top of the mould. 2. The CBR tests will be conducted with and without reinforcement. Specimen for testing the CBR has done by taking the soil mass of about 4.5 kg, which was passed through a sieve of size 20mm.OMC which we had gotten from standard proctor test will added in the soil mass and mixed thoroughly until lumps vanishes. keep the CBR mould ready by fixing it to base plate and spacer disc of size 3,7cm will be placed at the bottom of the mould, after being mixed the soil mass is poured in CBR mould which is having a size of diameter 15 cm and height of 17.5cm and it will compacted in three layers by giving 25 blows for each layer for light compaction. After compacting the second layer collar will be placed and compacting the 3 rd layer the collar will be removed and the extra part of soil mass is trimmed until it gets to smooth surface Reinforcement is done at certain depth from top of the specimen editor@iaeme.com

7 Comprative Study of Reinforced Soil of Bidar Dirstic With Geogrid-1, Geogrid-2 & Geo-Membrane 3. After conducting without reinforcement CBR strength is higher in lateritic soil as comparing to the Black cotton soil. 4. With reinforcement also CBR strength is higher in lateritic soil as comparing to the Black cotton soil. 5. After the reinforcement Physical and strength characteristics of the soil are improved For the single layer reinforcement in lateritic soil. 1. In the black soil the geogrid-1 is more strength as comparing to Geogrid-2 & geomembrane the strength of the Geogrid-1 is increases at 8cm depth from the top of the specimen. 2. As comparing to Geogride-1 the strength of the Geogrid-2 is low but higher than the geo-membrane. The strength of the Geogrid-2 increases at 4cm depth at the top of the specimen. 3. The strength of the geo-membrane is low as comparing to Geogrid-1 & Geogrid-2 4. The geo-membrane strength increases at the 4cm depth from the top of the specimen For multi-layer reinforcement of BC soil. 1. In multi-layer reinforcement also Geogrid-1 is more strength as comparing Geogrid-1 & geo-membrane. The strength is high at the depth 4cm, 8cm & 12cm from the top of the specimen. 2. As per comparing to Geogrid-1 the strength of Geogrid-2 is low but higher than the geo-membrane. The strength is increases at 4cm, 8cm & 12cm depth of the specimen. 3. The strength of the Geo-membrane is low as comparing to the Geogrid-1 & Geogrid- 2.It s Strength is increases similarly at the depth of 4cm, 8cm & 12cm top of the specimen. Sample Penetration at 2.5mm Penetration at 5mm Lateritic soil Black cotton soil Table 2 CBR for without Reinforcement of lateritic soil & B.C Soil specimen Figure 5 CBR for without Reinforcement lateritic soil & B.C Soil specimen Sample Sample 1withoutgeogrid-1 4cm &8cm depthsample-2 4cm,8cm&12cm depth sample-3 Black cotton soil Lateritic soil Table 3 Summary of CBR Values with and without reinforcement Geogrid-1 for multi layers 67 editor@iaeme.com

8 N. Vijay Kumar, SS. Asadi and A.V.S. Prasad Figure 6 Summary of CBR Values with and without reinforcement Geogrid-1 for multi layers. Sample Soil without geogrid-1 4cm depth 8cm depth 12cm depth Black cotton soil Lateritic soil Table 4 Summary of CBR Values with and without reinforcement Geo-membrane Figure 7 Summary of CBR Values with and without reinforcement Geo-membrane Sample Soil without geogrid-1 4cm&8cm depth 4cm,8cm&12cm Depth Geogrid Geogrid Geo-membrane Table 5 Summary of CBR Values with and without reinforcement for multi-layer in BC soil with different depth. Figure 8 Summary of CBR Values with and without Reinforcement of multi-layer in BC soil with different depth 68 editor@iaeme.com

9 Comprative Study of Reinforced Soil of Bidar Dirstic With Geogrid-1, Geogrid-2 & Geo-Membrane Sample Soil without geogrid-1 4cm depth 8cm depth 12cm depth Geogrid Geogrid Geo-membrane Table 6 Summary of CBR Values with and without Reinforcement of lateritic soil with different depth Figure 9 Summary of CBR Values with and without Reinforcement of lateritic soil with different depth. 6. CONCLUSION The investigation that has been performed on geo-grid reinforced soil gives wide variety of results on several issues from which the following qualitative conclusions can be drawn:- 1. CBR value increased up to 27.84% and 35.43% when sample was reinforced with geogrids-1 at a depth of 8 cm for B C soil and lateritic soil respectively. 2. CBR value increased up to 22.07% and 49% when sample was reinforced with geogrids-2 at a depth of 4 cm for B C soil and lateritic soil respectively. 3. CBR value increased up to 7.59% and 15.18% when sample was reinforced with geomembrane at a depth of 4 cm for B C soil and lateritic soil respectively. 4. Maximum CBR value was observed, up to 30.37% and 36.7% when sample was reinforced with geogrids-1 in 3 layers at a depth 4cm, 8cm and 12cm for B C soil and lateritic soil respectively. 5. CBR value increased up to 24.06% and 39.77% when sample was reinforced with geogrids-2 in 3 layers at a depth 4cm, 8cm and 12cm for B C soil and lateritic soil respectively. 6. CBR value increased up to 9.49% and 12.65% when sample was reinforced with geomembrane in 3 layer at a depth 4cm, 8cm and 12cm f B C or soil and lateritic soil respectively 7. Increase in CBR value was higher by providing reinforcement of geogrids-1 at a 8cm depth is than 4cm & 12cm depth for both lateritic soil & B C soil. 8. CBR value increased by placing reinforcement of geogrids-2 at a depth of 4cm in both lateritic soil and Black cotton soil. 9. CBR value increased by placing reinforcement of Geomembrane at 4cm depth as compared to 8cm and 12cm depth editor@iaeme.com

10 N. Vijay Kumar, SS. Asadi and A.V.S. Prasad 10. Comparing all three types of geosynthetic materials, geogrids-1 is more effective than Geogrids -2 & Geomembrane. 11. Three layers reinforcement at depth 4cm & 8cm&12cm is more effective under CBR test as compared to two layers reinforcement at 4cm & 8cm depth. REFERENCES [1] Srinivas Rao, B. and Jagloxshmi S (2008), Neetu B. Ramteke, Prof. Anil Saxena and Prof. T.R. Arora (2014) Stabilization of Black Cotton Soil with sand and cement as a subgrade of pavement IJESRT pg. ( ) [2] S. A. Naeini & R. Ziaie Moayed (2009) Effect of plasticity index and reinforcement on the CBR value of soft clay. International journal of Civil Engineering. Vol. 7, No.2. [3] Hossein Moayedi et.al (2009 Sina Kazemian, Arun Prasad, Bujang B. K. Huat (2009) Effect of Geo-grid Reinforcement Location in Paved Road Improvement EJGE Vol. 14. [4] J.G. Zornberg et.al (2009) & R.Gupta (2009) Reinforcement of pavements over expansiveclay subgrade Proceeding of the 17th International conference on soil mechanics and Geotechnical engineering. Pg ( ) [5] Dr. D.S.V. Prasad et.al (2010) and Dr M. Anjan Kumar (2010) Behavior of reinforced sub bases on expansive soil sub-grade GJRE Vol. 10. [6] Professor Stelin, V.K., Prof. Ravi, E. and Arun Murugen, R.B (in 2010) [6] Effect of geogrid on Compressive strength and Elasticity modulus of Lime/ Cement treated soil EJGE Vol.15. [7] Sarika Dhule et.al (2011) [7] Sarika B. Dhule and S.S. Valunjkar Improvement of flexible pavement with use of geo-grid EJGE Vol.16. [8] A. K. Choudhary, K. S. Gill and J. N. Jha (2011) Improvement in CBR values of expansive soil sub-grades using geo-synthetics IGC J-233. [9] Pradeep Singh and K.S. Gill (2012) [9] CBR Improvement of clayey soil with Geo-grid Reinforcement IJETAE Vol.2 ( ) [10] Dr. P Senthil kumar & R. Rajkumar (2012) [10].Effect of Geo-textile on CBR Strength of Unpaved Road with Soft Sub-grade EJGE Vol. 17. [11] Evangelin Ramani Sujatha and Vignesh Jayaraman (2012) Improving the strength of subgrade using geo-grids. [12] Rakesh Kumar and P.K.Jain (2012) [12].Mihai Iliescu and Ioan Ratiu (2012) Geo-grid reinforced road sub-grade stabilization design methodology. [13] Prof Mayura Yeole and Dr. J. R. Patil (2013)) Reinforcement of pavements over expansive clay subgrade Proceeding of the 17th International conference on soil mechanics and Geotechnical engineering. Pg ( ). [14] K. Vasudhar, CH. Rama Krishna and Afshan sheikh, Analysis of Structure with the Pile Foundation on Low Safe Bearing Capacity of Soils, International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 2017, pp [15] S. Siva Gowri Prasad, Ch. Vasavi and K. Praveen Sai, Behaviour of Stone Column in Layered Soils Using Geotextile Reinforcement, International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 8, August 2017, pp editor@iaeme.com