THE DUCTILITY BEHAVIOR OF HYBRID FIBER REINFORCED CONCRETE FORMED BY USING FIBERS OF DIFFERENT ASPECT RATIO

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 9, September 2018, pp , Article ID: IJCIET_09_09_055 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed THE DUCTILITY BEHAVIOR OF HYBRID FIBER REINFORCED CONCRETE FORMED BY USING FIBERS OF DIFFERENT ASPECT RATIO Rudraswamy M.P Research Scholar, Visvesvaraya Technological University, Belagavi, Karnataka, India B.R Patagundi S.G. Balekundri Institute of Technology, Belagavi, Karnataka, India K.B Prakash Government Engineering College Haveri, India ABSTRACT It is seldom possible to get a proper design mix which gives higher ductile performance under different loadings, the current research work is concentrated on ductile performance of hybrid fiber reinforced concrete. The insertion of two or more fibers into the design mix is known as hybridization and combination of them can be termed as hybrid. The individual strands or fibers will influence the concrete design mix and there is a considerable improvement in the mechanical properties. In this work totally five different types of fibers were used namely, Steel fiber, Galvanized iron fibres, High density polyethylene fibres, Waste plastic fiber and Poly propylene fiber. All of these fibers are added to the concrete design mix by volume fraction, for experimental work mainly two design aspect ratio like 40 and 100 are considered. The parameters of this inspection are modulus of rupture under ultimate load and service load, ultimate and service load deflections. The standard dimensions of the specimens used for this work is 150mmX150mmX500mm, all the specimens are tested under universal testing machine with fixed dial gauge. Three different aspect ratio (AR) has been considered here 40, 100, In the experimental procedure 2% of steel fiber from 40 AR and 2% of steel fibers from 100 AR were checked and 1% of 40AR and 1% 100 AR were taken, combined together to get hybrid fiber reinforced concrete. The same procedure has been followed for other fibers also. Compared to 40 and 100 AR, hybrid fiber i.e AR gave much better results. Key words: Reinforced Concrete, Fibers, Hybrid Fiber, testing machine editor@iaeme.com

2 The Ductility Behavior of Hybrid Fiber Reinforced Concrete Formed by using Fibers of Different Aspect Ratio Cite this Article: Rudraswamy M.P, B.R Patagundi and K.B Prakash, The Ductility Behavior of Hybrid Fiber Reinforced Concrete Formed by using Fibers of Different Aspect Ratio. International Journal of Civil Engineering and Technology, 9(9), 2018, pp INTRODUCTION Concrete is one of the finest example for brittle material, this brittle nature is because of poor fracture toughness and low tensile strain capacity. This brittle nature can be suppressed or can be modified with the addition of discrete fibers, all fibers are randomly distributed in the concrete mix. The addition of fibers in the design mix are effective in arresting both microcracks and micro-cracks. To obtain better performance, two or more different types of strands or fibers are mixed together. These combination of fibers will together constitute a composite member, when mixed into the design mix and composite section can achieve better engineering properties than the normal design mix. Different types of fibers of varied sizes, shapes were taken for the current research work. The reinforced material is used to increase bonding strength in the concrete mix as well as crack arresting property can also be achieved with the use of hybrid fibers as reinforcement in design concrete mix [1]. Individual fiber strength and hybrid fiber strengths are varied considerably, steel fibers alone and combination of recron fiber; hooked end steel fiber have showed good ductile characteristics [2]. Based on Neuro Fuzzy model ductility characteristic performance has been checked for different types of fibers by varying proportions [3] In this paper ductility characteristics and behavior of hybrid fibers hitherto not reported in previous research works is presented for hybrid fiber reinforced concrete by taking different aspect ratio like 40, 100 and By keeping these aspect ratio in mind experimental work has been started in accordance with IS 10262:2009. This research work focuses on totally five types of fibers namely, Steel fiber, polyolefin-steel hybrid fiber reinforced system. In this system, steel fiber, Galvanized iron fibres, high density polyethylene fibres, Waste plastic fiber and Poly propylene fiber. Each fibers have their own characteristic properties, to check which fiber mix will give higher performance under different types of loadings are checked here. Individual fiber itself will help to arrest the cracks in the design concrete mix, so here attempt has been made to achieve more strength by mixing two or more fibers together, under this ductility performance of designed mix has been studied. 2. OBJECTIVE OF THIS PROJECT The main objective of this proposed research work is to study the ductile characteristic properties of hybrid fiber reinforced concrete produced by using fiber of different aspect ratios. In this research work it is intended to use steel fibers, GI fibers, HDPE fibers, waste plastic fibers and polypropylene fibers of different aspect ratios. The objective of this experimental work is To find out the ductile behavior of concrete made of hybrid fiber reinforced concrete using fibers of different aspect ratios editor@iaeme.com

3 Rudraswamy M.P, B.R Patagundi and K.B Prakash 3. MATERIALS AND METHODS 3.1. Materials Cement In this experimental work, Ordinary Portland Cement (OPC) 43 grade conforming to IS: was used. For the practical work the cement used was Bharathi cement, which had been brought from the local distributors. The properties of Ordinary Portland Cement (OPC) 43 grade is indicated below in the table 3.1. Table 3.1 Properties of Cement (OPC 43) Sl. No. Material Property of OPC of 43 grade Results obtained 1 Specific gravity Fineness 4% 3 Normal consistency 30% 4 Initial setting time 30 minutes 5 Final setting time 5 hour 45 minutes Fine Aggregates Locally available river sand belonging to zone II of IS was used for the research work. Mainly fine aggregates are added to fill the gaps in concrete mix and to avoid air bubbles inside the concrete mix, so fine aggregates plays major role in the concrete design. The physical properties of fine aggregates used are shown in table 3.2. Table 3.2 Physical Properties of Fine Aggregate Sl. No. Material Property Results obtained 1 Specific gravity Bulk Density 1752 Kg/m 3 3 Water absorption 1.0% 4 Zone II Coarse Aggregates Locally available Crushed aggregates confirming to IS are used in this dissertation. The physical properties of coarse aggregates in table 3.3. Table 3.3 Physical Properties of Coarse Aggregate Sl. No. Material Property Results obtained 1 Specific gravity Bulk Density 1782 Kg/m 3 3 Water absorption 0.6% Steel Fibres (SF) In the present research work steel Fibres having dimensions of 1mm thickness 40mm long which gives 40 Aspect ratio and 1mm thickness and 100 mm length which gives an aspect ratio of 100 were used. As we made a literature survey out of different types of Steel Fibres crimped shape Steel fibres were found suitable for our design. The density of fiber is 7850 kg/m3 and ultimate tensile strength 395 MPa respectively. Steel fibres were took from stewools india (p) ltd. Nagpur editor@iaeme.com

4 The Ductility Behavior of Hybrid Fiber Reinforced Concrete Formed by using Fibers of Different Aspect Ratio Galvanized iron fibres (GIF) GI fibres were procured locally. Round GI wire of 1mm diameter was cut to the required length of 40 mm and 100 mm giving an aspect ratio of 40 and 100. The ultimate strength and density of fibres was found to be 395 MPa and 7850 kg/m3 respectively High density polyethylene fibres (HDPEF) High density polyethylene fibers are procured by cutting oil cans available in petrol pumps they are cut to a length of 40 mm, 100mm and width of 1mm obtaining aspect ratio of 40 and 100. Density of HDPE fiber was found to be 900 kg/m Waste plastic fiber (WPF) The waste plastic fibres were obtained by cutting the waste plastic buckets. Fibres are cut to a length of 40 mm, 100 and width of 1mm obtaining aspect ratio of 40 and 100. Density of WPF = 280 kg/m Poly propylene fiber (PPF) Poly propylene fibres are readily available in the market in standard dimensions. The fibres used here are of length 6 mm and 12 mm which is prescribed by the manufacturers for the concrete work. The density of PPF = 930kg/m MIX DESIGN FOR M30 GRADE CONCRETE According to Indian Standard code: M 30 was designed using IS method of mix design. The mix proportion for M 30 grade concrete is given in the following Table 4.1. Table 4.1 Mix proportion for M 30 grade concrete Sl. Coarse Grade of concrete Cement Fine aggregate W/C No aggregate 1. M Mixing Calculate the material required for 3 cubes, 3 cylinders, 3 beam, 3shear and 3 impact specimen using the mix proportion by mass. The mixing procedure was done according to following steps: Separately mix the cementitious materials and fibers as shown in fig 4.1. Dry mix the sand and cementitious materials and fibers. Add coarse aggregate to it and mix it thoroughly to achieve cement particles on each and every coarse aggregate. Add the calculated quantity of water to the dry mix and mix thoroughly to get homogeneous mix as shown in fig editor@iaeme.com

5 Rudraswamy M.P, B.R Patagundi and K.B Prakash Figure 4.1 Mix ingredients Figure 4.2 Wet mix 4.2. Casting The following procedure is adopted to cast the specimens. Place the moulds on the vibrating table and put the wet concrete mix inside the moulds in three layers. Put on the button of vibrating table and along with that tamping has to be done using standard tamping rod. Vibration should not be more, otherwise segregation will take place. After filling the moulds with wet concrete, level the surface and give the designation to it. Demould the specimen after 24 hours as shown in fig 4.3. Figure 4.3 Casting of Beams 4.3. Ductility Test Experimental investigation is carried out on prepared specimens which are having dimensions of about 100mmX100mmX500mm. All the specimens are casted and cured for 28days

6 The Ductility Behavior of Hybrid Fiber Reinforced Concrete Formed by using Fibers of Different Aspect Ratio Specimens are tested under universal testing machine by keeping dial gauge at the bottom, loadings are applied on the specimens and corresponding deflection reading are noted. Ductility factor (µ) = Δ U/ Δ Y Where, Δ U= ultimate deflection Δ Y= yield deflection Figure 4.4 Deflection Test on Concrete Beam 5. TEST RESULTS: Following tables give the ductility test results of hybrid fiber reinforced concrete produced by using fiber of different aspect ratios. Variations of ductility characteristics are depicted in the form of graph as shown in figure Table 5.1 Ductility Factor Test Results Fibers Aspect Ratio Deflection factor STEEL (40+100) GI (40+100) HDPE (40+100) WPF (40+100) PPF ( ) editor@iaeme.com

7 Ductility Factor Rudraswamy M.P, B.R Patagundi and K.B Prakash DEFLECTION Steel GI HDPE WPF PPF Description of fibers (40+100) Figure 5.1 Variation of Ductility factor 6. CONCLUSIONS Steel fiber reinforced concrete having an aspect ratio of 40, showed ductility factor 2.27 and for aspect ratio 100 the value ductility value is 2.11 which is less than 40 Aspect Ratio. Hybrid fiber reinforced concrete made by the combination of 40 and 100 aspect ratio has showed ductility of about 2.59, which is more than 40 and 100 aspect ratio. GI fiber of 40 aspect ratio have ductility factor 2.21 and for 100 aspect ratio From the graph we can conclude that hybrid fiber i.e aspect ratio has higher ductility value. Similarly, HDPE fiber, WPF fiber and PPF fibers and their hybridization has higher ductility values, shown in figure. If we compare five different types of fibers like steel fiber, GI fiber, HDPE fiber, WPF fiber and WPF fiber, the concrete specimens designed with steel fibers as reinforcement s shows higher ductility value. REFRENCES [1] Yung, W., Yung, L. and Hua, L., Bending and Uniaxial Tensile Test on Concrete Reinforced with Hybrid Steel Fibres, Journal of Materials in Civil Engineering, September 2013, pp [2] Banthia, N. and Nandakumar, N., Crack Growth Resistance of Hybrid Fibre-Reinforced Cement Composites, Cementitious Concrete Composite, Vol. 25, No. 1, 2003, pp [3] Yao, W., Li, J., and Wu, K., "Mechanical Properties of Hybrid Fiber-Reinforced Concrete at Low Fiber Volume Fraction," Cem. Concr. Res., Vol. 33, No. 1, 2003, pp [4] Zhiguo You, " Ductility and strength of hybrid fibre reinforced self-consolidating concrete beam with low reinforcement ratios, Proceeding Engineering 65, pp , [5] Banthia, N. and S.M. Soleimani, Flexural Response of Hybrid Fibre-Reinforced Cementitious Composites, ACI Mater. J., 102 (6): [6] Singh, S.P., Y. Mohammadi and S.K. Kaushik, Flexural Fatigue Analysis of Steel Fibrous Concrete Containing Mixed Fibres, ACI Mater. J., 102 (6): [7] Nehdi, M. and J.D. Ladanchuk, Fiber Synergy in Fiber-Reinforced Self- Consolidating Concrete, ACI Mater. J., 101 (6): [8] Romualdi, J.P. Batson, G.B. (1963) Behaviour of reinforced cement concrete beams with closely spaced reinforcement, Journal of American Concrete Institute, Proceedings Vol. 60. No.6, June 1963, PP editor@iaeme.com

8 The Ductility Behavior of Hybrid Fiber Reinforced Concrete Formed by using Fibers of Different Aspect Ratio BIOGRAPHIES Mr. Rudraswamy M. P. is pursuing Doctorate of Philosophy under Visvesvaraya Technological University, Belagavi, Karnataka. He completed B.E in civil engineering from STJIT, Ranebennur and Mtech in Structural Engineering from Govt College of Engineering Haveri. He worked as an assistant professor in STJIT college till 2015 and presently working in RRIT Bangalore. Total teaching experience is 5years, His current research interests include An investigation on the behavior of hybrid fiber reinforced concrete produced by using fibers of different aspect ratios. He is an active member of MISTE and also having a good publication records 5 International journals. Dr.B. R. Patagundi holds B.E. and M.Tech. Degrees from NITK, Suratkal Karnataka; PhD from Shivaji University, Kolhapur. He is Professor in S.G. Balekundri Institute of Technology, Belagavi, Karnataka, India. He has over 28 years of teaching experience. His area of interest is on performance of concrete by partially replacing fine aggregate with granulated blast furnace slag and cement with fly ash. He has published 12 papers in international/national journals and about 25 papers in international/ national conferences. Dr. K. B. Prakash, principal of Government engineering college Haveri. He is having 27years of total teaching experience and 2years of industrial experience. He obtained his degree from NIE Mysore and M.Tech in structural engineering and also got his phd degree from Walchand college of engineering, Sangali. He had published around 200 International/National journal papers and Proceedings, Ph.D. scholars are more than 14. He is an active member in research and review committee, board of examination, Board of studies research grants committee, estate board committee etc at VTU Belgaum editor@iaeme.com