Durability Properties of Concrete with Natural sand and Manufactured sand

Transcription

1 Durability Properties of Concrete with Natural sand and Manufactured sand P.hanmugavadivu Asst.Professor, Department of Civil Engineering Sona College of technology Salem, Tamilnadu, India R.Malathy Principal, Excel Engineering College Komarapalayam, Namakkal, Tamilnadu, India line 3: City, Country Abstract The Concrete is a mixture which generally consists of cement, fine aggregate, coarse aggregate and water. Natural river sand is the most commonly used material as fine aggregate in concrete. It has been already proved that the conventional concrete containing natural sand is having good strength and durability properties. Nowas there is a lot of demand for the natural sand in the world. So it s the time for us to discover a new alternative material for replacing the sand. Many researchers are going on the replacement of fine aggregate by various industrial wastes like fly ash, pond ash, recycled aggregate, crushed glass, quarry waste, etc., In this paper one of the industrial wastes such as manufactured sand is used as fine aggregate in concrete. Manufactured sand can be defined as residue, tailing or other non-valuable material after the extraction. Here the various durability tests are discussed for M3 grade concrete with natural sand and manufactured sand is used as fine aggregate. The various tests performed are alkali aggregate reaction test, chemical attack, rapid chloride ion penetration and water permeability test. From the test results it is observed that the concrete blended with 3 % natural sand and 7 % manufactured sand having good durability properties. Keywords-Manufactured sand, Alkali aggregate reaction, Chemical attack, Rapid chloride penetration, Water permeability. I. INTRODUCTION For a long time concrete was considered to be a durable material requiring little or no maintenance. It is true, except when it is subjected to highly aggressive environment. Now a s concrete structure are built in highly polluted urban and industrial areas, aggressive marine environments, harmful subsoil water in coastal area and many other hostile conditions. The environmental pollution is increasing by at particularly in urban areas due to industrial atmosphere. So it is necessary to concentrate on durability of the concrete structures. The durability of the concrete is defined as its ability to resist weathering action, chemical attack, or any other process of deterioration. Durable concrete will retain its original from, quality and serviceability when exposed to its environment. When designing a concrete mix or designing a concrete structure, the exposure condition at which the concrete is supposed to withstand is to be assessed in the beginning with good judgment. In case of foundation, the soil characteristics are also required to be investigated. In the past only strength of concrete was considered in the concrete mix design procedure assuming the strength of concrete is an important factor for all other desirable properties of concrete including durability. Although compressive strength is a measure of durability to a great extent it is not entirely true that the strong concrete is always a durable concrete. In order to predict the durability properties of concrete the following test are carried out and resulted down here. II. LITERATURE REVIEW Sawich.Z. and Heng S.S. (1995) studied the influence of powdered limestone and W/C ratio on the durability of concrete in 5% NaSO. The results shows that a beneficial influence of a powdered lime stone on concrete durability was observed when w/c <.. Above this value the powdered lime stone has almost no essential effect on sulphate resistance. R. Ilangovan, N. Mahendran and K. Nagamani () made a study on concrete by 1% replacement of natural sand by quarry dust. They concluded that the compressive strength, flexural strength and durability properties of concrete made of quarry dust are nearly 1% more than the conventional concrete. K.Perumal and R.Sundarajan (3) reported that the quarry rock dust could be used as alternative replacement of natural sand in concrete. They observed that using quarry rock dust reduces the cost without affecting the strength. They concluded that the weight loss and strength of concrete with quarry rock dust is considerably less. Nisnevich.M., et al (3) studied when Crushed sand is blended with natural sand, which reduces the volume of voids as 1 % and also reduces the required water content. They found that the optimum percentage of crushed sand to natural sand is 1: 1.5 (or) 1.5: 1. Stella L.Marusin (3) has investigated the reversible reaction of sodium sulphate solution on concrete. Salvador Villalobos.,et al (5) studied the evaluation, testing and comparison between the crushed manufactured sand and natural sand. They concluded that the blended manufactured sand can be utilized in concrete. Karthik Obla, Colin lobo, Proc. of the International Conference on Science and Engineering (ICSE 11) Copyright 11 RG Education Society ISBN:

2 Proc. of the International Conference on Science and Engineering (ICSE 11) Lionel lemay (5) have made a study on durability properties of concrete. They informed that the compressive strength loss considerably low in concrete with quarry rock waste compared to conventional concrete. Leslie Struble (5) has made a study on durability of concrete and he has suggested many methods for improving concrete durability properties. Md Saffiuddin,S.N.Raman, M.F.M.Zain (7) investigated the utilization of quarry waste fine aggregate in concrete mixtures. They concluded that the use of rock dust enhancing the durability of concrete. Ilangovan.R et al., () studied the Strength and Durability Properties of Concrete containing Quarry Rock Dust as Fine Aggregate It was found that the compressive, flexural strength and durability studies of concrete made of quarry rock dust are nearly1% more than the conventional concrete. III. EXPERIMENTAL INVESTIGATION The materials used are Portland pozzolana cement, Natural River sand, Manufactured sand, mm down size Coarse aggregate. The properties of materials are shown in Tables 1, & 3. TABLE I. PROPERTIES OF CEMENT S.No Description Values 1 Specific gravity 3.15 Fineness(bysieve analyis).% 3 Consistency 9% Initial setting time 11 minutes 3% N.S 7% 9 % N.S % 1 1% N.S 9% 11 % N.S 1% NIL I NIL I NIL I NIL I Natural Sand N.S, Manufactured Sand, Specific Gravity G, Fineness modulus F.M, Surface moisture S.M, Water absorption W.A Table 1 show that the properties of cement are within the allowable limits. From Table, it is observed that the properties of coarse aggregate values satisfy the standards. Table 3 gives the properties of natural river sand and manufactured sand. From Table 3, it is noticed that the Fineness modulus values of fine aggregate is increased with the increase in percentage of manufactured sand. i.e., the fine aggregate content changes from the Zone III to Zone I. This means the fine aggregate content is from fine to coarse while increasing the quantity of manufactured sand. It is observed that the surface moisture content of fine aggregate is increased while increasing the proportions of manufactured sand. This may be due to the manufactured sand is washed with water. IV. MIX PROPORTIONS FOR M3 GRADE CONCRETE The mix design is prepared for various proportions of M3 grade concrete. It is shown in Table. TABLE II. PROPERTIES OF COARSE AGGREGATE S.No Description Values 1 Specific gravity.73 TABLE IV. Proportions MIX PROPORTIONS FOR M3 GRADE CONCRETE Cement: F.A : C.A : W/C Bulk density 153. kg/m3 3 Surface moisture.% Water absorption 1.% 5 Fineness modulus.9 A 1: 1.31 : 3.9 /.9 B 1 : 1.3 : 3.9 /. C 1 : 1.33 : 3. /. D 1 : 1. :.95 /.7 TABLE III. PROPERTIES OF FINE AGGREGATE S.NO Proportions G F.M S.M W.A ZONE (%) (%) 1 1% N.S % III 9% N.S 1% III 3 % N.S % II 7% N.S 3% I 5 % N.S % I 5 % N.S 5% I 7 % N.S % I E 1 : 1. :.95 /.7 F 1 : 1.1 :.95 /.7 G 1 : 1.7 :.95 /. H 1 : 1.7 :.95 /. I 1 : 1.7 :.95 /. J 1 : 1.3 :.95 /.5 39

3 Proc. of the International Conference on Science and Engineering (ICSE 11) K 1 : 1.7 :.95 /. From Table it is found that the quantity of fine aggregate increases while using the manufactured sand. This may be due to the high specific gravity of manufactured sand. It is also observed that the w/c ratio is reduced with the increase in percentage of manufactured sand. This may be due to the high surface moisture content of the manufactured sand. V. TESTING DETAILS A. Alkali aggregate reaction test This test is conducted as per IS: 3 (Part 7) 193. This test is developed to provide a way to identify reactive aggregates. The mortar bars (5mm x 5 mm x 5 mm) are cast with cement and fine aggregate in the ratio of 1:3 and water / cement ratio of.7. Three mortar prisms are cast. The mortar prisms are cured for hours in a room at 1 ± C, demoulded, and immersed in water in a closed container maintained at C. After hours, the length of the specimens is measured. They are then immersed in a closed container of 1M sodium hydroxide solution maintained at C. The specimens are removed periodically from the containers and measured before significant cooling can occur. The length change of the prisms is measured up to 3 s after casting Alkali aggrgate reaction test Age in s Figure 1. Alkali aggregate reaction test results 1 % Natural Sand 7 % Manufactured sand 1 % Manufactured sand Results & Discussion Figure 1 shows the alkali aggregate reaction test results. From the figure, it is observed that the Percentage expansion is reduced for manufactured sand. This may be due to the grain size of the manufactured sand is coarser and the better packing is developed. Due to the better packing the presence of moisture is reduced, So that the percentage expansion is less in manufactured sand. The test results indicate that the reactive silica in manufactured sand is less when compared to natural river sand. So the manufactured sand is harmless. B. Chemical attack For performing the chemical attack, the tests namely acid attack, chloride attack and sulphate attack are conducted. For each test 9 cubes of size 15 mm x 15 mm x 15 mm are cast for M 3 grade concrete. The weight and the compressive strength at the end of s are calculated and they are placed in the sulphuric acid, sodium chloride and sodium sulphate solutions of.1normality. The weight loss and the loss in compressive strength of the concrete cubes are calculated. L oss of weigh t in % Loss of weight due to acid attack 9th Loss Age of weight in sin % 1 s s Figure. Loss of weights due to acid attack Loss of weight due to chloride attack 9th Age in s 1 s s Figure 3. Loss of weights due to chloride attack Loss of weight due to sulphate attack 9th 1th th Loss of weight Age due to in sulphate s attack in % Figure. Loss of weights due to sulphate attack M 3 A M 3 B M 3 C M 3 A M 3 B M 3 C M3 A M3 B M3 C 37

4 Proc. of the International Conference on Science and Engineering (ICSE 11) Loss of strength in % Loss of strength due to acid attack 9th 1th th Loss of strength Age due in to s acid attack in % Figure 5. Loss of strength due to acid attack Loss of strength in % Loss of strength due to chloride attack 9th 1th Loss of strength Age due to in s chloride attack in % th M3 A M3 B M3 C M3 A M3 B M3 C Figure. Loss of strength due to chloride attack allowed to dry for s and the four faces of the cubes are painted to prevent the penetration of water from sides. Then the top surface is effectively sealed to achieve water tightness. Glass bottles are kept in position to collect the water percolating through the specimen. Compressor is started and the pressure is applied at the rate of.5 MPa to the water column. The quantity of water passing through the cube is collected at the bottom, in the glass bottle through the funnel, being maintained in humid atmosphere to prevent losses due to evaporation. The operating pressure, quantity of water collected, time of observation etc., at intervals is recorded. The test is continued till the uniform rate of flow is obtained. The co-efficient of permeability is calculated using the formula K=QL/ATH Permeability coefficient x1-7cm/sec 1 1 Permeability Test A B C ProportionsM3 Loss of strength in % Loss of strength due to sulphate attack 9th 1th th Loss of strength Age due in to s sulphate attack in % M3 A M3 B M3 C Figure. Water permeability test Figure shows the water permeability test. From the Figure, it is noted that the permeability values are reduced while using the manufactured sand. This may be due to the less voids of better interlocking bond between the aggregate and cement paste. Figure 7. Loss of strength due to sulphate attack Figure shows the losses in weight of the concrete cubes in acid, chloride and sulphate attack at various periods. From the Figure, it is observed that the weight losses are lesser in manufactured sand and it is least for the optimum proportion of 7 % of manufactured sand when compared to the concrete with natural river sand. This may be due to the less entry of the solution in to the pores of concrete. Figure 3 shows the strength losses of the concrete cubes in acid, chloride and sulphate attack at various periods. It is noticed that the strength losses are lesser in manufactured sand and it is least for the optimum proportion of 7 % of manufactured sand when compared to the concrete with natural river sand. Due to the better interlocking of manufactured sand, the loss of strength is less in manufactured sand. D. Rapid chloride penetration test In the AASHTO T77 (ASTM C1) test, a water-saturated, 5 mm thick, 1 mm diameter concrete specimen is placed in one reservoir contains 3. % NaCl solution and another reservoir contains.3 M NaOH solution and subjected to a V applied DC voltage for hours. The total charge passed is determined and this is used to rate the concrete. Charges passed in couloumbs 3 1 Rapid chloride permeability Test A B C C. Permeability test The test is conducted as per IS: 35 (Part 7) 193. The standard cubes of size 15 mm x 15 mm x 15 mm are cast and cured for s. After curing period, it is taken out and Figure 9. Proportions M3 Rapid chloride permeability test 371

5 Proc. of the International Conference on Science and Engineering (ICSE 11) Figure 5 shows the rapid chloride penetration test results. From the Figure, it is found that the chloride ion penetrability is high for concrete with natural sand and it is reduced while using manufactured sand. This may be due to the grain size of the manufactured sand is coarser and the better packing is developed. Due to the better packing the permeability of the concrete is reduced. From the above results, it is observed that the optimum proportion of 7 % manufactured sand gives better results. VI. CONCLUSION The percentage expansion due to alkali aggregate reaction is 17 % less while using the manufactured sand. The weight loss due to acid attack, chloride attack and sulphate attack is reduced as 5 % while using 7 percentages of manufactured sand. The loss in compressive strength due to acid attack, chloride attack and sulphate attack is reduced as - % for the optimum proportion of manufactured sand. The permeability of the concrete with manufactured sand is % less when compared to the natural river sand. The chloride ion penetration is less for the concrete with manufactured sand and it is also reduced for high grades of concrete REFERENCES [1] Abhay Kumar jain (3) study on addition of superplasticizer to increase concrete s resistance to sulfuric acid Aggregate coatings effect on concrete pavement [] Ilangovan,R.,() Studies on Strength and behaviour of concrete by using quarry waste as fine aggregate, Proceedings of All India Seminar on Materials and Machines for construction, New Age International, pp [3] Ilangovan.R et al., () studied the Strength and Durability Properties of Concrete containing Quarry Rock Dust as Fine Aggregate ARPN Journal of Engineering and Applied Sciences, vol. 3, no. 5, October. [] Kalgal M.R et al., (7) Strength and durability of concrete with pond ash as fine aggregate. The Indian Concrete Journal, March 7. [5] K.Permual and R.Sundarajan (3) Quarry rock dust could be used as alternative replacement of natural sand in concrete Proceedings of National Seminar on Futuristic in Concrete and Construction Engineering, SRM university, Chennai. [] S.N.Raman,M.F.M.Zain,Md.Safuddin(), Utilization of quarry waste fine aggregate in concrete mixtures. Journal of Applied Sciences Research, 3(3):, 7. [7] Shanmugavadivu P.M., Malathy.R.,(9), A comparative study on Mechanical Properties of Concrete with Manufactured Sand International journal of Technology World, Malaysia, Vol.5, ISSN 1 11, Oct Nov 9, pp [] IS 19 Specification for Portland Pozzolona cement. [9] IS 33:197 Specification for coarse and fine aggregate from natural sources of concrete. 37