STRENGTH AND DURABILITY EVALUATION OF SISAL FIBRE REINFORCED CONCRETE

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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_083 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed STRENGTH AND DURABILITY EVALUATION OF SISAL FIBRE REINFORCED CONCRETE K. V. Sabarish Assistant Professor, Department of Civil Engineering, Vels University, Tamil Nadu, India K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surender Students, Department of Civil Engineering, Vels University, TamilNadu, India ABSTRACT Concrete is strong in compression and weak in tension. So we will provide the reinforcement to the concrete. Majorly steel is used as the reinforcement. Many of the researches are in progress to find a substitute to this material. Many investigations proposed artificial fibres. In this project we would like to take the naturally available fibre named sisal fibre is taken as a substitute material to the reinforcement and studied the properties. Inclusion of fibre reinforcement in concrete can enhance many of the mechanical characteristics of the basic materials such as fracture toughness, flexural strength and resistance to fatigue, impact, thermal shock and spalling. In recent years, a great deal of interest has been created worldwide on the potential applications of natural fibre reinforced cement (NFC) based composites. In the present work, it is aimed to investigate the strength and durability with sisal fibre reinforcement. From the results it shows that, sisal fibre reinforced concrete has improved the characteristics of workability, strength and durability. Keywords: Durability, Natural fibres, Strength, sisal Cite this Article: K. V. Sabarish, K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surrender, Strength And Durability Evaluation of Sisal Fibre Reinforced Concrete, International Journal of Civil Engineering and Technology, 8(9), 2017, pp INTRODUCTION The manufacture of concrete, primarily its ingredients; cement and aggregates; presents various sustainability issues that need to be dealt. The production of concrete has always lead to massive exploitation of natural resources. Manufacturing 1 tone of Portland cement requires quarrying 1.5 tons of limestone and clay (Civil and Marine, 2007). Moreover, continuous extraction of natural aggregate; sand and gravel; from river beds, lake and other editor@iaeme.com

2 K. V. Sabarish, K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surrender water bodies over the years have led to erosion which eventually leads to flooding and landslides. Further, there is less filtration of rainwater due to reduced amount of natural sand, causing contamination of water needed for human consumption. 1.4 tons of Ordinary Portland cement being produced yearly around the globe contributes to 5 percent of greenhouse gas, carbon dioxide, emissions worldwide (Civil and Marine, 2007). Not only burning fuel to heat the kiln emits carbon dioxide, but also decomposition of limestone emits even more gas. These identified problems clearly, contribute significantly to climate change. The ideal target to partly solve the above phenomenon is to develop a sustainable system loop which can turn resources which are land filled as waste materials into useful products in the construction industry, thus preserving the natural resources. Several attempts have been made for improving the durability performance of natural fibre composites for recent decades. The techniques so far adopted are fibre modification, matrix modification and combined fibre-matrix modification. The matrix modification so far adopted are reducing alkalinity by replacing ordinary Portland cement OPC with supplementary cementations materials such as silica fume, fly ash, slag and met kaolin, replacing with alumina cement, gypsum, addition of natural and synthetic polymers, and carbonation of matrix The fibre modification includes the use of impregnating agents such as static acid, forming, natural resins, silica fume slurry, silanes, polymers etc.and Kraft pulps. It is reported that the matrix modification by replacement of OPC with 40% of silica fume and also use of immersed natural fibre with silica slurry could be the effective means of reducing Embrittlement of natural fibre composites.also, the concrete specimens are exposed to water and NaCl curing and behavior is evaluated in terms of strength and durability. The study parameters considered are compressive strength, split tensile strength, flexural strength and flexural toughness. 2. SISAL FIBER: Sisal fibre is one of the most widely used natural fibres and is very easily cultivated. It has short renewal times and grows wild in the hedges of fields and railway tracks. Nearly 4.5 million tons of sisal fibre is produced every year throughout the world. Tanzania and Brazil are the two main producing countries. Sisal fibre is a hard fibre extracted from the leaves of the sisal plant (Agave sisalana). Though native to tropical and sub-tropical North and South America, sisal plant is now widely grown in tropical countries of Africa, the West Indies and the Far East. Sisal fibres are extracted from the leaves. A sisal plant produces about 200±250 leaves and each leaf contains 1000±1200 fibre bundles which are composed of 4% fibre, 0.75% cuticle, 8%dry matter and 87.25% water. So normally a leaf weighing about 600 g will yield about 3% by weight of fibre with each leaf containing about 1000 fibres. Figure 1 Sisal fibre editor@iaeme.com

3 Strength And Durability Evaluation of Sisal Fibre Reinforced Concrete Table 1 Chemical Composition of Sisal Fibre Cellulose 65% Hemicelluloses 12% Lignin 9.9% Waxes 2% Total 100% 3. MATERIALS USED Ordinary Portland cement (OPC) of grade 53 conforming to IS , good quality river sand as fine aggregate and crushed granite stone as coarse aggregate with maximum size of 20mm conforming to IS and portable water were used. The well-known natural fibre named sisal fibre with maximum available length of 300mm was cut into smaller lengths of 10mm with aspect ratio of 100 and this was used throughout the experiment. Natural rubber latex polymer was chosen and used to improve the properties of sisal fibre reinforced composites. Table 2: Physical properties of cement SI.NO Specifications Results 1 Type OPC 2 Specific Gravity Initial setting time 40 minutes 4 Final setting time 450minuts 5 Fineness 2% 3.1. Fine aggregates: The fine aggregate used was locally available river sand without any organic impurities and conforming to IS: The fine aggregate was tested for its physical requirements such as gradation, fineness modulus, specific gravity and bulk density and is shown in table3. Table 3 Properties of fine aggregate SI.NO Specifications Results 1 Type River sand 2 Specific gravity Grading Zone III 3.2. Coarse Aggregate: The crushed coarse aggregate obtained from the local crushing plant is used in the present study. The physical properties of coarse aggregate like specific gravity, water absorption and fineness modulus are tested in accordance with IS: 2386 are given in Table 4. Table 4: Properties of Coarse Aggregate SI.NO Specifications Results 1 Fineness modulus Specific gravity Water absorption editor@iaeme.com

4 K. V. Sabarish, K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surrender Water: Water used for mixing and curing was potable water, which was free from any amounts of oils, acids, alkalis, sugar, salts and organic materials or other substances that may be deleterious to concrete or steel. The ph value should not be less than 6. Scope: Concrete is strong in compression and week in tension. To increase the tensile strength of the concrete we are adding sisal fibre. Also it resists the plastic shrinkage cracks. This sisal fibre is a natural product that is available in the fields and if this could replace the reinforcement in the concrete it would be a gigantic change in the construction i ndustry. Preparation and testing of specimen: Based on four different mixes, cube (150mm x 150mm x 150mm) for compression test, cylinder (300mm x 150 mm) for split tensile test and prism (500mm x 100mm x 100mm) for flexure test were casted for each mixes. A set of 3 specimens as average has been prepared for each mix and for each test and cured for 3 different ages Viz. 7, 14 and 28 days under water for evaluating hardened characteristics of concrete. For durability test, same set of specimens after attaining 28 days of age under water were taken out and conditioned for another 28 days by immersing under alkaline solution prepared using 10% sodium chloride with a ph of 12. The ph was maintained throughout the conditioning period. After aging under alkaline medium, the specimens were taken out and tested for evaluating durability in terms of compressive strength, split tensile strength, flexural strength and flexural toughness. The results based on the above tests were discussed under the following section. Table 5 Physical properties of river sand and coarse aggregate Sl.No Property River sand Coarse aggregate 1 Specific gravity Water absorption (%) Bulk density (kg/m 3 ) Fineness modulus Zone II -- Table 6 Physical properties of sisal fibre. Sl.No Property Value 1 Average length (mm) Average diameter (mm) Density (g/cm 3 ) Average Tensile strength (N/mm 2 ) Elongation (%) Water absorption (%) 76.7% editor@iaeme.com

5 Strength And Durability Evaluation of Sisal Fibre Reinforced Concrete Objective: The main objective is to study the effect on utilization of sisal fibre in the concrete as the reinforcement and in this investigation the fibre is mixed in different proportions by cutting it into small pieces of size 3 to 5 cm. To study the mechanical and transport properties of concrete for Compressive test on concrete cubes ( mm) Split tensile strength on cylinders (Ø 100 mm & 200 mm long) Evaporation test on cubes ( mm) Water absorption test on cubes ( mm) Moisture migration test on cubes ( mm) 4. RESULTS AND DISCUSSIONS 4.1. Effect of sisal fiber on fresh properties of concrete: Fig.2 to 5 shows the shapes of slumps for different mixes. From this it is very clear that addition of sisal fiber improves the workability even for concrete mix with incorporation of sisal fibres. Of all the mixes, the increased slump of 75mm and 45mm is achieved for the mix M1 and M3 respectively. The percentage increase of M1 is about 97% with respect to the reference mix and M3 mix is about 18% and 29% when compared with reference and sisal fibre concrete without polymer addition. Although the sisal fibre concrete with sisal fiber shows reduced workability than M1 mix, the improvement is observed than that of sisal fibre concrete without polymer addition. In general, from the literature it is evident that the workability of natural fibre reinforced composite are greatly affected. From this study, it could be noted that addition of latex polymer compensated the slump loss of about 8% exhibited by sisal fibre reinforced concrete (M2). Figure 2 Slump for M0 mix 38mm Figure 3 Slump for M1 mix-75mm Figure 4 Slump for M2 mix-35mm Figure 5 Slump for M3 mix-45mm editor@iaeme.com

6 K. V. Sabarish, K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surrender 4.2. Effect of sisal fiber on hardened properties of concrete: The various hardened properties such as Compressive strength, Split tensile strength and Flexural strength are evaluated for 7, 14 and 28 days for various mix and are given in Table Compressive strength Irrespective of type of mix, all the specimens showed increased compression values as age of concrete increases and maximum values are reported for 28 days aging. In all curing ages, the maximum compressive strength is achieved for M3 specimens and this increase is almost 16.5% and 13% greater than that of reference specimen and sisal reinforced specimen without polymer. Also, it is noted that M1 specimen shows greater strength next to M3, which expresses the superior performance of latex in terms compressive strength than specimens prepared without latex addition. Moreover, the strength attainment of latex polymer modified concrete was found to be quick when compared with concrete without latex. Thus from the results, it is noticed that the 28 days compressive strengths of latex concrete ranges from times and concrete without latex is times that of 7 days strength. Therefore, reference concrete and sisal fibre concrete modified with latex polymer is suitable for repair works and other works which requires earlier strength attainment. Figure 6 Compression testing machine Split tensile strength As that of compressive strength, split tensile strength also increases with increase of age of specimens. Also, the entire specimen shows greater strength when compared with reference specimen irrespective of the ages of concrete. From that, the concrete prepared with latex and sisal presented the maximum split tensile strength and the improvement of strength of 28 days specimens are compared and is almost 36% higher than that of reference specimen (M0) and 15.5% than unmodified sisal fibre concrete (M2). Also the concrete modified with latex (M1) shows strength increment upto 13% than M0 but 4% decrement than sisal fibre concrete (M2). In all respects, sisal fibre reinforced concrete with and without latex shows better performance under split tensile test. Figure 7 Split tensile testing machine editor@iaeme.com

7 Strength And Durability Evaluation of Sisal Fibre Reinforced Concrete Flexural strength Under all ages of curing, concrete specimens offered maximum strength for specimens prepared with latex and sisal fibre. Also, as in previous cases, increase of flexural strength is observed with increase of curing period. The maximum strength attainment is achieved by M3 specimens under all curing ages and the 28 days cured specimens are compared here. Therefore, the M3 concrete showed 28% and 12% higher strength than the reference and M2 concrete specimens. The strength variation under flexure follows the same trend as in case of split tensile strength. Next to M3 concrete M2 shows better performance and is almost 15% and 2% greater than M0 and M1 respectively. From this, it is evident that the incorporation of sisal fibre imparts greater strength under flexural loading. Figure 8 Flexural testing machine Compressive strength Split tensile strength Flexural strength Mix (N/mm ID ) (N/mm 2 ) (N/mm 2 ) 7 days 14 days 28 days 7 days 14 days 28 days 7 days 14 days 28 days M M M M Table 7 Hardened properties of concrete specimens after 7, 14 and 28 days water curing 5. CONCLUSIONS The addition of natural sisal fibre composites improved the workability about 29% without polymer. All mechanical characteristics of various mixes are showing better performance when both sisal fibre and polymer are used in one particular concrete specimen. Early gain of compressive strength for sisal fibre reinforced concrete with polymer modification will proves to be a better option for repair works. The increase of compressive strength, split tensile strength and flexural strength is about 13%, 15.5% and 12% for sisal fibre concrete. As overall, the strength and durability parameters are found to have positive impact on sisal fibre composites in the presence of natural rubber latex polymers. One day strength results are not to be estimate for the fibre content as the increase in the fibre percentage the setting time of the concrete is delayed. Freshly prepared Sisal fibre contain some gelatinous chemical reagents which may affect the chemical properties of cement in concrete When the percentage of fibre is increased by more than 1% reduction in mechanical properties is observed. Reduction in strength is due the increase in the fibre percentage and that may leads to porous structure by the agglomeration. Increase in strength up to 1% is due to utilization of water present in fibre for chemical reaction at time editor@iaeme.com

8 K. V. Sabarish, K. Dhanasekar, R. Manikandan, R. Ancil, R. Venkat raman and P. Selva surrender of curing and less concentration of fibre created densely compacted medium in cement concrete. The addition of the fibre in small amounts will increase the tensile strength. Addition of fibres not only increases tensile strength but also increases bond strength, decreases permeability. Toughness of concrete also increases by the addition of the fibre. REFERENCES: [1] Sabarish.K.V, Experimental Studies Of Sisal Fibre In Portland Cement Concrete Elements On Durability, Advances In Natural And Applied Sciences, April & 2016, PP, [2] Sabarish.K.V, Experimental Investigation on Strength and Durability Properties of Sisal Fiber Reinforced Concrete, International Journal of Chemical Sciences, August & 2016, PP [3] Sabarish.K.V, Experimental Studies Of Agave Sisalane In Concrete Elements On Durability SSRG International Journal Of Civil Engineering, (2'iceis-2017), Special Issue, April 2017,PP [4] H. E. Gram, Durability of Natural Fibres in Concrete, Swedish Cement and Concrete Research Institute, S Stockholm, CBI Fo 1:83, [5] L. K. Aggarwal, Cement & Concrete Composites, Bagasse reinforced cement composites, Vol. 17, pp , [6] G. Ramakrishna and T. Sundararajan, Impact strength of a few natural fibre reinforced cement mortar slabs: a comparative study, Cement & Concrete Composites, Vol. 27 pp , [7] A. Kriker, G. Debicki, A. Bali, M. M. Khenfer, and M. Chabannet, Mechanical properties of date palm fibres and concrete reinforced with date palm fibres in hot-dry climate, Cement & Concrete Composites, Vol. 27 pp , [8] Didier Snoeck and Nele De Belie, Mechanical and self-healing properties of cementitious composites reinforced with flax and cottonised flax, and compared with polyvinyl alcohol fibres, Biosystems Engineering, Vol. 111, pp , 2012 [9] Ganesh R Kalagi, Dr. Rajashekar Patil, Narayan Nayak, M. Ambarish, HN. Mayura, MK. Niranjan, Kishor Kumar Aroor, V. Karthik, Ananth Mohan Mallya and Sunil Kumar Shetty. Experimental Study on Damping Properties of Sisal/Flax Fibre Reinforced Composite Material. International Journal of Mechanical Engineering and Technology, 8(2), 2017, pp [10] G. Ramakrishna and T. Sundararajan, Long-Term Strength and Durability Evaluation of Sisal Fibre Composites Part-I: Cement Mortar Composites, International Journal Of Civil Engineering And Technology (IJCIET), Volume 4, Issue 1, January- February (2013), pp editor@iaeme.com