EFFECT OF TYPE AND COMPOSITION OF CHEMICAL ADMIXTURE ON PROPERTIES OF PRODUCED CONCRETE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 6, November-December 216, pp , Article ID: IJCIET_7_6_31 Available online at ISSN Print: and ISSN Online: IAEME Publication EFFECT OF TYPE AND COMPOSITION OF CHEMICAL ADMIXTURE ON PROPERTIES OF PRODUCED CONCRETE Luma Abdul Ghani Zghair Civil Engineering Department, College of Engineering, Al - Mustansiriyah University, Iraq Salwa Rhman Rasheed Civil Engineering Department, College of Engineering, Al - Mustansiriyah University, Iraq ABSTRACT This work aims to study the effect of different types of superplastizicer. The experiment work included test on slump flow, compressive strength, splitting and modulus of rupture. Water cement ratio and cement content were maintained constant (.4 and 3 Kg/m3) respectively. Three different admixture (polycarboxylic ether melamine formaldehyde, and of sulphonated naphthalene) have been used. Four dosage of superplastizicer were adopted (., 1, 1., 2 and 2.) liters for 1 Kg of cement. Based on the experimental results, superplasticizers based on Modified polycarboxylic ether are more efficient than other superplasticizers, concerning the degree of workability, compressive strength, and flexible strength Over dosage of SP found to deteriorate the properties of concrete, signs of bleeding and segregation were noticed. However, if the dosage levels of SP are lower than the optimum dosage, increase in admixture dosage may help to enhance the concrete characteristics Key words: Supeplastizicer; compressive; splitting; flexural; slump flow. Cite this Article: Luma Abdul Ghani Zghair and Salwa Rhman Rasheed, Effect of Type and Composition of Chemical Admixture on Properties of Produced Concrete. International Journal of Civil Engineering and Technology, 7(6), 216, pp INTRODUCTION ACI [1] defined admixtures as a material differently than water, cementitous materials, aggregate and fibers, used as a component of a cementitious mixture to modify its properties, and these material can be added to the batch before or during mixing ACI 212.4R-6 [2]. SP are divided under four major types depending on it chemical composition namely, Sulfonated Melamine Formaldehyde Condensed (SMF), Sulfonated Naphthalene Formaldehyde Condensed (SNF), Modified Lignosulfonates (MLS) and Other different types such as Polyarchylates, Sulfonates, Polysterene polymers etc Shah et al. [3] used two types of superplastizecer from two different families (namely, SP-1 (Visco) of Carboxylic ether group and SP-2 (Glenium), of Polycarboxylates (PCO), to study their effect on concrete 29 editor@iaeme.com

2 Effect of Type and Composition of Chemical Admixture on Properties of Produced Concrete properties in fresh and hardened state. They concluded that, using SP-1, was more effective in enhancing the concrete properties, (workability, compressive and flexural strength) Gayathri et al. [4] presented a study about using different types of superplastizer. Two of these types belong to the same family, polycaboxylate based super plasticizicer (SP1 and SP2), and the other type was naphthalene based superplastizicer. They concluded that, concrete mixes with type SP3 need higher dosage of superplastizicer to make the same initial slump flow Maroliya [] reported an experimental assessment of workability for normal concrete. Three different chemical admixtures were used in this assessment plasticizer of calcium lignosulphate (CLS), superplasticizers of sulphonated melamine formaldehyde condensate (SMF) and sulphonated naphthalene formaldehyde condensate (SNF). Based on slump cone test, using concrete mixes with SNF shows better performance than the other two chemical admixtures at low dosage levels (.) %. It was also shows that using SNF at.7 and 1.% dosage level, a sign of segregation and bleeding was observe compare to SMF and CLS Saeed et al. [6] in this area compared the effect of superplasticizers Carboxylic Ether names (Gelenium-1 and Viscocrete) on concrete properties (compressive, splitting strengths and workability). They reported that, both superplasticizer improved the concrete properties in the hardened state, the improvement was more pronounced by Gelenium-1 In addition, the workability of concrete mixes increased, but in case of Gelenium-1, it has collapsed. Shah et al. [7] studied the influence of deceasing or increasing the dosage of melamine polycondensade superplasticizer on concrete compressive strength. In this work, different curing condition was carried out and dosage range from (. -2) % has been used. They reported that, in all cases, water curing up to 28 days testing and.% superplasticizer showed highest strength, while the lowest value of strength was obtained with the addition of 1% superplasticizer. Daniela et al. [8] presented a study about the use of different kinds and dosage of polymer admixtures (Naphthalene-sulfonate, modified polycaboxylate and ether polycaboxylate). The effect of these admixtures on compressive strength and consistency of concrete mixes was studied. The experimental result have proved that, admixture type polycaboxylate ether are much stronger compared with the two other admixtures. 2. RESEARCH SIGNIFICANT Many information can be given by manufactures might appear to be exaggerated. It is necessary for a civil engineer to study the chemicals effects of superplasticizers, and then quantify the benefits of superplasticizers to produce an economical design of structural units. This study has been undertaking to understand the effect of increasing or decreasing deferent types of superplastizicer modified polycarboxyel ether (PC), melamine formaldehyde (MF) and salphonated naphthalene (SN) on the ( compressive, tensile strength) and slump of normal concrete 3. EXPERIMENTAL WORK 3.1. Materials and Mix Proportions This study will focus on normal concrete. The binders used included Iraq ordinary Portland cement (Al kufa). The cement was tested and checked according to IQS :1984 [9]. The chemical and physical properties for the cement are listed in (Table1). The fine aggregate was natural sand with a fineness modulus of 2.8, Zone 2. Crushed coarse aggregate with a maximum nominal size of 2 mm. The aggregate was tested and checked according to IQS 4:1984 [1] editor@iaeme.com

3 Luma Abdul Ghani Zghair and Salwa Rhman Rasheed Table 1 Chemical and physical properties of Al- Kufa cement Oxides Percentages IQS No. /1984 [9 ] CaO SiO Fe 2 O Al 2 O MgO 2. Not grater than % SO Not grater than 2.8% Loss on agent L.O.I% 2.6 Not grater than 4% Insoluble residue I.R%.98 Not grater than 1.% C 3 A 6.7 Physical properties IQS No. /1984 Specific surface area (cm 2 /g) 3 2 Initial Setting Time Final Setting Time (hr:min) 1:6 2:7 4 min 1 hours Compressive strength 3 days (Mpa) 7days (Mpa) 4. RESULT AND DISCUSSION 4.1. Effect of Admixtures on Slump Test As shown in (Table 2). The value of slump is different depending on the types of the admixture used. At constant dosage. The increase in slump flow is more pronounced in the case of PC, for example: at dosage of (1.) liter for 1 Kg cement, the slump increased from (1 mm to 24 mm), (1 mm to 11mm) and (1 mm to 98mm) for PC, SN and MF respectively, mixtures incorporating modified polycarboxyel ether showed higher slump flow comparable with other concrete mixes. This result can be attributed to the following: At The initial hydration of the cement paste, a surface charge in both magnitude and direction may promote the early flocculation of hydrating cement particles, but they can be neutralized and superseded by the ionic charge of the superplasticizer molecules. The presence of adsorbed SP molecules on the hydrating cement reduce the interaction between the particles through the electrostatic repulsive forces and then steric repulsion[7] 2. In the case of PC, The reason for this anomaly is probably due to that PC admixtures has a different chemical structure from the other types of admixtures it s consist of a carboxylic ether polymer with long side chains. At the beginning of the mixing process it initiates the same electrostatic dispersion mechanism as the traditional superplasticisers, but the side chines linked to the polymer backbone generates a steric hindrance which greatly stabilizes the cement particles ability to separate and disperse. Steric hindrance provides a physical barrier between the cement grains, as a result, flowable concrete is obtained editor@iaeme.com

4 Effect of Type and Composition of Chemical Admixture on Properties of Produced Concrete Mix notation *Not: slump flow before adding SP = 1 mm Table 2 Slump test for concrete mixes * 4.2. Compressive Strength Test (Table 3) presents the result of compressive strength at 7 and 28 days for each concrete mixes.. In all cases, the compressive at 28 days curing was higher comparable with age 7 days curing. As shown in Figure 1 to Figure 3. Concrete mixes Dosage of SP liter for 1 Kg cement Table 3 Compressive strength for normal concrete mixes. Dosage of SP liter for 1 Kg cement Modified Polycarboxyel ether Compressive strength of concrete mixes ( MPa) According to BS 1881: Part 116, [12] Modified Polycarboxyel ether Slump (mm) Melamine formaldehyde Melamine formaldehyde Sulphonated Naphthalene M M M M4 2 collapse M 2. collapse collapse collapse Sulphonated Naphthalene 7 days 28 days 7 days 28 days 7 days 28 days M M M M M Lfor 1 Kg cement 1L for 1 Kg cement 1.L for1 Kg cement 2L for 1 Kg cement 2. L for 1 Kg cement Cmpressive strength( MPa ) Day Figure 1 Compressive strength for concrete mixes with Melamine formal dehyde superplastizicer editor@iaeme.com

5 Luma Abdul Ghani Zghair and Salwa Rhman Rasheed. Lfor 1 Kg cement 1L for 1 Kg cement 1.L for1 Kg cement 2L for 1 Kg cement 2. L for 1 Kg cement Cmpressive strength( MPa ) Day Figure 2 Compressive strength for concrete mixes with Modified Polycarboxyel ether superplastizicer. Lfor 1 Kg cement 1L for 1 Kg cement 1.L for1 Kg cement 2L for 1 Kg cement 2. L for 1 Kg cement Cmpressive strength( MPa ) Day Figure 3 Compressive strength for concrete mixes with Sulphonated Naphthalene superplastizicer From Figure 4 increasing the dosage of superplasticizer will increase the amount of densification of the matrix of concrete so that the compressive strength well is also increased [4] [13]. However the increase is more pronounced by PC admixtures, the highest value of compressive strength achieved was (39.6) for M3 with modified polycarboxyel ether superplastizicer comparable with other concrete mixes as shown in Figure editor@iaeme.com

6 Effect of Type and Composition of Chemical Admixture on Properties of Produced Concrete Compressive strength ( MPa ) L for1kg cement 1L for1kg cement 1. L for1kg cement 2L for 1Kg cement 2.L for 1Kg cement Modified Polycarboxyel ether Melamine formaldehyde Sulphonated Naphthalene Types of admixture Figure 4 Compressive strength of concrete mixes with different types and dosage of superplastizicer It can be also observed that, the compressive strength increases by increasing the dosage of sp and it has a maximum at a specific dosage, and then it decreases. Therefore, this is the optimal dosage, which gave the maximum compressive strength at 28 [13]. As mentioned above, and when the dosage of SP exceeds the optimum one so this will make the concrete suffer from segregation and bleeding, as a result, the compressive strength will decreases.[7] [14] [1] 4.3. Splitting and Modulus of Rupture Tests (Table 4 and ) presents the result of Splitting and flexural tests at 7 and 28 days for each concrete mixes respectively. From Figure and Figure 6 the Splitting and modulus of rapture tests at 28 days curing was higher comparable with age 7 days curing. In addition, the modulus of rapture and splitting tensile strength have been increased with [the three types] of the SP, but the increase is more clear in case of PC and this may due to rehological properties of the admixtures. Concrete mixes Table 4 Splitting tensile strength for normal concrete mixes. Dosage of SP liter /1 Kg cement Splitting tensile strength of concrete mixes ( MPa) ASTM C [16] Modified Polycarboxyel ether Melamine formaldehyde Sulphonated Naphthalene 7 days 28 days 7 days 28 days 7 days 28days M M M M M editor@iaeme.com

7 Luma Abdul Ghani Zghair and Salwa Rhman Rasheed Concrete mixes Table Modulus of Rapture for normal concrete mixes. Dosage of SP liter /1 Kg cement Modulus of Rapture of concrete mixes ( MPa) ASTM C 78-21[17] Modified Polycarboxyel ether Melamine formaldehyde Sulphonated Naphthalene 7 days 28 days 7 days 28 days 7 days 28 days M M M M M Splitting tensile strength ( MPa ) L for1kg cement 1L for1kg cement 1. L for1kg cement 2L for 1Kg cement 2.L for 1Kg cement Modified Polycarboxyel ether Melamine formaldehyde Sulphonated Naphthalene Types of admixture Figure Splitting tensile strength for normal concrete mixes with different types and dosage of superplastizicer Modulus of Rapture ( MPa ) L for1kg cement 1L for1kg cement 1. L for1kg cement 2L for 1Kg cement 2.L for 1Kg cement Modified Polycarboxyel ether Melamine formaldehyde Sulphonated Naphthalene Types of admixture Figure 6 Modulus of Rapture of concrete mixes with different types and dosage of superplastizicer editor@iaeme.com

8 Effect of Type and Composition of Chemical Admixture on Properties of Produced Concrete. CONCLUSION 1. For all types of SP, there is a marked improvement in the workability of fresh concrete. 2. The normal slump of 1 mm could be increased to (11) mm and (98) mm, by using super plasticizers (MF and SN) respectively, and greater than 2 mm by super plasticizers (PC) 3. At higher dosage of SP (2.liter / 1 kg cement )signs of bleeding and segregation were noticed 4. The contribution of modified polycarboxylic ether based SP is more pronounced in terms of increase in the workability, compressive strength, and tensile strength of normal concretes. REFERENCE [1] ACI 116R, Cement and Concrete Terminology, ACI Publication, USA, 2. Chemical Admixtures for Concrete [2] ACI 212.4R-4 Guide for the use of high-range water-reducing admixtures (Superplasticizers) in concrete. [3] Shah1, A., Khan, S., Khan, R., and Jan, I., U., '' Effect of high range water reducers on the properties and strength development characteristics of fresh and hardened concrete '' IJST, Transactions of Civil Engineering, Vol. 37, 213, pp [4] Gayathri, D., M., and Elson, J., ''Effect of Re-Dosing Superplasticizer to Regain Slump on Concrete '' International Journal of Innovative Research in Advanced Engineering Vol. 1, 214, pp [] Maroliya M., K., '' An assessment of workability of ordinary concrete by using chemical admixtures '' IOSR Journal of Engineering (IOSRJEN) Vol. 2, 212, PP 72-7 [6] Saeed A., Attaullah, S., and Ajmal S., '' Comparative study of two commercially available superplasticizers on the properties of concrete '' concrete & structures Singapore, 27, PP:1-9 [7] Shah S., N., R., Aslam, M., Shah, S A and Oad, R., Behaviour of Normal Concrete Using Superplasticizer under Different Curing Regimes '' Pak Pakistan. J. Engg. & Appl. Sci. Vol. 1, 214 PP: [8] Daniela F., Mirela L., Victoria B., and Gheorghe H., '' Superplasticizer polymeric additives used in concrete '' Material Plastic, Vol. 49,212, PP: [9] Iraqi Specification, No. /1984., "Portland cement [1] Iraqi Specification, No. 4/1984, "aggregate ". [11] ASTM C494 /C494M- 16 Standard Specification for Chemical Admixtures for Concrete [12] BS 1881: Part 116, Method for mesurment of Compressive Strength of Concrete Cubes [13] Tamrakar, R., and Mishra, S., P., '' Experimental studies on property of concrete due to different ingredient based superplasticizer '' International journal of since, engineering and technology research, Vol. 2 May, 213, pp: [14] Alsadey, S., " Effect of superplasticizer on fresh and hardened properties of concrete '' Journal of Agricultural science and engineering, Vol. 1, No. 2, 21, pp [1] Alsadey, S., '' Influence of Superplasticizer on Strength of Concrete International Journal of Research in Engineering and Technology (IJRET) Vol. 1, No. 3, 212, PP: [16] ASTM C496-21, Standard Test Method for Splitting Tensile of Cylindrical Concrete Specimens [17] ASTM C78-21, Test method for bending strength of concrete [18] Adanagouda, Mahesh and Dr. H.M. Somasekharaiah, An Experimental Study on Properties of the Concrete for Replacement of Sand by Stone Waste for Different Types of Cement with Chemical Admixture, International Journal of Civil Engineering and Technology (IJCIET), 6(2), 21, pp [19] Chinnu Mariam Ninan and Dr. M. Nazeer, Investigation on Strength Development of Portland cement Slag Metakaolin Cementitious System. International Journal of Advanced Research in Engineering and Technology (IJARET), 7(), 216, pp editor@iaeme.com