Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber)

Page 1

GRD Journals- Global Research and Development Journal for Engineering | Volume 6 | Issue 1 | December 2020 ISSN- 2455-5703

Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber) B Mary Devika Department of Civil Engineering Vishnu Institute of Technology, Bhimavaram, Andhra Pradesh B Durga Vara Prasad Department of Civil Engineering Vishnu Institute of Technology, Bhimavaram, Andhra Pradesh

K Suseela Department of Civil Engineering Vishnu Institute of Technology, Bhimavaram, Andhra Pradesh

Abstract Soil stabilization is the process which involves enhancing the physical properties of the soil in order to improve the strength, durability etc. by blending additives. By blending cotton fibers to the soil the CBR values will improve and thickness of pavement layer also reduces. By the application of soil stabilization method in construction the cost gets reduced. The liquid limit of the soil with addition of cotton fibers was found to be decreasing when compared to liquid limit of soil alone. The plastic limit of the soil decreases with the blending of fibers. The shrinkage limit of the soil was increased with increase in fibers. The MDD of the soil with addition of cotton fibers by weight of soil is found to be increasing upto 0.75% after that it decreases and the corresponding OMC is decreased with addition of fibers. The shear strength of soil decreased substantially with addition of cotton fibers. The CBR value of the soil increased substantially. Different tests were conducted in order to determine the different characteristics and properties of the red soil and obtained with following results. The liquid limit of the soil alone was found to be 36.6%. The MDD of the soil with addition of 0.25%, 0.5% cotton fibers by weight of soil is found to be decreased by 0.84% and 0.76% , 1.0% cotton fibers by weight of soil is found to be increased by 0.11 % and 16.98% respectively and the corresponding OMC is decreased by 15.62%, 21.87% and 33.75% respectively. The shear strength of the soil with the addition of 0.25%, 0.5%, 0.75% and 1% of cotton fibers is found to be decreased by 38.57%, 38.57%, 35.25% and 5.85%. The CBR value of the soil with addition of 0.25%, 0.5%, 0.75% and 1.0%, cotton fibers by weight of soil is found to be expanded. flexible pavement design thickness before stabilization is obtained as 450mm and after stabilization is obtained as 250mm.The estimated cost for constructing flexible pavement before stabilization of soil is obtained as 4018051 Rs/Km and after stabilization of soil is obtained as 3721895 Rs/Km. the estimated cost after stabilization is found to be decreased by 7.35%. Keywords- Cotton Fiber, CBR Test, Stabilization

I. INTRODUCTION The land is used everywhere for different structures, from ordinary buildings to skyscrapers, bridges to airports, and from rural roads to expressways. All the civil engineering structures are located on different soil sheets. Soil can be elucidating as a material consisting of rock particles, sand, silt, and clay. On average 1 lakh sq. km area is covered by lateritic soil deposits, 5 lakh sq. km area is covered by sand dunes and 3 lakh sq. km area is covered by black cotton soil. Geo synthetics are synthetic products made from many types of polymers which may be either woven or Non-Woven. Polymers are used to enhance the characteristics of soil and have provided a practical way of constructing civil engineering structures economically. In this study, we are employing bamboo fibers as geosynthetic material for the stabilization of soil. Soil properties differ greatly and the construction of structures depends on the soil's bearing capacity, so to increase the load-bearing capacity, we need to stabilize the soil. Soil gradation is also a very significant function to keep in mind when dealing with soils. The soils may be well-graded, which is desirable since they have fewer voids or graded uniformly, which although sound stable, has more voids. During the construction phase, if weak soil strata are encountered, the usual practice followed is replacing the weak soil with some other good quality soil. The cost of subgrade preparation by replacing the poor soil with good quality soil is higher than that of subgrade preparation by using various stabilization techniques to stabilize the locally available soil. Stabilization can effectively increase the strengthgiving parameters of the soil to the required amount. It enhances the strength of the soil, thus, improving the soil bearing capacity. It is more economical both in terms of cost and energy to improve the bearing capacity of the soil rather than going for a deep foundation or raft foundation ItIt is often used on slopes to provide the soil with more stability. Sometimes soil stabilization is also used to stop soil erosion or formation of dust, which is very useful mainly in dry and arid weather. For soil water-proofing, stabilization is often done; this prevents water from entering the soil and thus protects the soil from losing its strength. It makes it easier to decrease the change in soil volume due to changes in temperature or moisture content.

All rights reserved by www.grdjournals.com

30


Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber) (GRDJE/ Volume 6 / Issue 1 / 006)

II. LITERATURE REVIEW A. AyushMithal and Dr. ShalinuShukla The effectiveness of the use of geotextiles as a soil stabilization reinforcement material for various engineering works was studied by AyushMithal and Dr. ShalinuShukla. Their aims were to study and implement geotextile properties (such as physical properties, mechanical properties, hydraulic properties, endurance properties and durability properties), geotextile fibers (natural and synthetic fibers), geotextile types, geotextile functions, geotextile application, geotextile properties, and geotextile properties., and impact of geotextiles on the environment. They have concluded that, due to the versatility of functions of geotextiles they can be used in many important civil engineering works. Not only does the use of geotextiles lower building costs, but it also lowers maintenance costs. B. Harshita Bairagi et al Harshita Bairagi et al., studied the effectiveness of jute fibers in controlling the swelling behavior of black cotton soil measured in lab with and without use of randomly reinforced jute fibers in the soil. Their objectives were to assess the soil's CBR values and unconfined compressive strength. The different tests conducted were sieve analysis, Atterbegs limits, differential swelling test, proctor test, CBR test and unconfined compression test. They concluded from the test that there was a significant improvement in the shrinkage limit, optimum moisture, dry density, CBR value and soil shear strength, and the swelling behaviour was also reduced by the addition of jute fibers to black cotton soil.

III. EXPERIMENTAL INVESTIGATION The Highway Research Board (HRB) classifies the soil strata as black cotton soil and uses effective sampling methods, such as the Core Cutter Method. To test the features such as Atterbegs Limits, i.e. Using Liquid Limit Casagrande Process, Plastic limit by rolling the sample to a thread of 3 mm diameter, Shrinkage limit with Shrinkage apparatus, Optimum Moisture Content, Grading by Sieve Analysis and Maximum Dry Density with Standard Proctor Test and California Bearing Ratio Test as well. The determination of the properties such as liquid limit, plastic limit, shrinkage limit, optimum moisture content, maximum dry density, CBR value, and shear strength for different concentrations of Geosynthetic material with black cotton. Using pavement design catalogues published by IRC SP: 20-2002, the pavement thickness design will be done. The road estimate is carried out by considering items such as Jungle Cutting, Roadway and Drains Earthwork Excavation, compacting and grading, etc., as per SR 2014-15 and suggested specifications for the stabilization mixture of Bamboo fibers as Geo Synthetic material. Using Unconfined Compression Test to conduct four days of soaked CBR and Shear test. In order to determine the various characteristics and properties of the soil, different experiments were performed. The procedure for each of the tests is described below. A. Wet Sieve Analysis By mechanical analysis, the distribution of the grain size is found. If the percentage fines are more there is a need to conduct wet sieve analysis. B. Liquid Limit Test The Casagrande test was performed to study the liquid limits of the soil. Using Casagrande's apparatus or the standard liquid limit test apparatus, the liquid limit is usually calculated by a mechanical method. The liquid limit is defined according to this method as the moisture content at which 25 blows or drops in the standard liquid limit apparatus will just close a groove of standardized dimensions cut by a specified amount in the sample by the grooving tool. C. Cone Penetration Method Another method used to test the soil's liquid limit is the method of cone penetration. The liquid limit of the soil is defined by the cone penetration method as the water content in the soil sample when the penetration depth of the standard cone is 20 mm. The depths to which the standard metal cone penetrates into soil paste samples prepared in 5 seconds with different water contents are measured. D. Plastic Limit Test It is necessary to perform plastic limit testing in order to study the Atterbegs limit. The plastic limit (PL) is the water content at which the soil rolled into a thread of the smallest possible diameter begins to crumble and is 3 mm in diameter. E. Shrinkage Limit Test In a remolded soil sample, the shrinkage limit (SL) is the maximum water content, expressed as a percentage of the Oven dry weight, where any further reduction in the water content does not cause the soil sample to decrease in volume or shrink.

All rights reserved by www.grdjournals.com

31


Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber) (GRDJE/ Volume 6 / Issue 1 / 006)

F. Compaction Test To study the density of the soil and its corresponding optimum moisture content, the Standard Proctor Test is performed. Soil compaction is a mechanical process by which, by eliminating air voids, the soil particles are constrained to be packed more tightly together. Soil compaction causes air voids to decrease and dry density to increase as a result. This can result in an increase in the shearing strength.. G. Unconfined Compression Test By performing an unconfined compression test, the shear strength of the soil is determined. Unconfined compression tests are performed on specimens of cohesive soil. If the lateral confining pressure Ďƒ3 is equal to 0, the test can be considered as a special case of the tri-axial compression test. The cylindrical test specimen may then be mounted directly in a compression testing system and the compressive load applied to it. H. California Bearing Ratio (CBR) Test The CBR test denotes a measure of the resistance of the standard plunger under controlled test conditions to the penetration of the soil or flexible pavement material.

IV. ANALYSIS OF DATA

Graph 1: Compaction Curve for Black cotton soil + 0.50% fibres

Graph 2: Compaction Curve for Black cotton soil + 0.75% fibres

Graph 3: Compaction Curve for Black cotton soil + 1 % fibres All rights reserved by www.grdjournals.com

32


Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber) (GRDJE/ Volume 6 / Issue 1 / 006)

Graph 4: Compaction Curve for Red soil + 0.25% fibers

Graph 5: Compaction Curve for Red soil + 0.5% fibers

Graph 6: Compaction Curve for Red soil + 0.75% fibers

V. DESIGN OF FLEXIBLE PAVEMENT Designing pavement constructed on soil that is not stabilized.  The commercial vehicles per day =0 to 15 veh/day.  The CBR value of soil as tested = 1.82 percentage  From the above graph, considering curve A the thickness of pavement =450mm.  Thickness of Sub Base material = 250mm.

All rights reserved by www.grdjournals.com

33


Designing of Flexible Pavement by using Geosynthetic Material (Cotton Fiber) (GRDJE/ Volume 6 / Issue 1 / 006)

     

Thickness of Base Coarse material =160mm. Thickness of Surface Coarse material = 40mm. Designing pavement to be constructed on stabilized soil The commercial vehicles per day= 0 to 15 veh/day. The CBR value of soil as tested = 5.40 %. From the above graph, considering curve thickness of pavement = 250mm

VI. RESULT AND DISCUSSION 1) 2) 3) 4) 5) 6) 7) 8) 9) 10)

The following conclusions are taken on the basis of the current experimental study. The black cotton soil sample has been classified as A-7-6, according to the Highway Research Board classification There is substantial increase in MDD with increase in addition of fibers upto 0.75% by weight beyond which it decreased. There is substantial decrease in OMC with increase in addition of fibers. In unconfined compression test it was observed that the shear strength of the soil has increased with the increase in percentage of cotton fibers, when compared to that of shear strength of soil tested without fiber. The shear strength of the soil is maximum when 1% (by weight of soil) of cotton fibers is added to it. Hence in order to obtain higher shear resistance 1% of fibers (by weight of soil) can be considered as the optimum fiber content. The California bearing ratio (CBR) of the soil alone is obtained as 1.82% and it increased to 5.41% after stabilizing it with optimum percentage of cotton fibers. In the case of red soil there is substantial increase in MDD with increase in addition of fibers. In unconfined compression test it was observed that the shear strength of the soil has decreased with the increase in percentage of cotton fibers, when compared to that of shear strength of soil tested without fiber. The California bearing ratio (CBR) of the soil alone is obtained as 4.28% and there substantial increase.

REFERENCES [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15]

M. Young, The Technical Writer’s Handbook. Mill Valley, CA: University Science, 1989. Sujit Kawade, Mahendra Mapari, Mr.Shreedhar Sharana” Stabilization of Black cotton soil with lime and Geo-grid” Vegulla Raghudeep, ”Improvement in CBR value of black cotton soil by stabilization it with vitrified polish waste” Ayush Mittal, Shalinee Shukla “GEOTEXTILE: AN OVERVIEW” Harshita Bairagi “International journal of engineering sciences and research technology Vikas Rameshrao Kulkarni “Experimental study of stabilization of B.C. soil by using Slag and Glass fibers” Olug benga O. Amu1, Akinwole A. Adetuberu” Characteristics of cotton Leaf Ash Stabilization on Lateritic Soil in Highway Construction” John Paul V. Antony Rachel Sneha M. ” Effect of random inclusion of cotton fibers on strength behaviour of flyash treated black cotton soil” I.S: 2720 (Part I)-1983 : “Indian standard for preparation of dry soil samples for various tests”, Bureau of Indian Standards Publications, New Delhi. I.S: 2720 (Part IV)-1985: “Indian standard for grain size analysis”, Bureau of Indian Standards Publications, New Delhi. I.S: 2720 (Part IV)-1985: “Indian standard for grain size analysis”, Bureau of Indian Standards Publications, New Delhi. I.S: 2720 (Part V)-1985: Indian standard for determination of liquid limit and plastic limit”, Bureau of Indian Standards Publications, New Delhi. I.S: 2720 (Part VII)-1980: “Indian standard for determination of water content- Dry density relationship using light compaction”, Bureau of Indian Standards Publications, New Delhi. I.S: 2720 (Part X)-1991 : “Indian standard for determination of unconfined compressive strength”, Bureau of Indian Standards Publications, New Delhi I.S: 2720 (Part XX)-1992 : “Indian standard for determination of Linear Shrinkage”, Bureau of Indian Standards Publications, New Delhi I.S: 2720 (Part XVI)-1965: “Indian standard for laboratory determination of CBR”, Bureau of Indian Standards Publications, New Delhi

All rights reserved by www.grdjournals.com

34


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.