INCORPORATION OF NANO PARTICLES IN PERVIOUS CONCRETE FOR WATER PURIFICATION AND STRENGTH IMPROVEMENT

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 2017, pp , Article ID: IJCIET_08_04_071 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed INCORPORATION OF NANO PARTICLES IN PERVIOUS CONCRETE FOR WATER PURIFICATION AND STRENGTH IMPROVEMENT Bolem Priyanka Civil Engineering Department, Rajiv Gandhi University of Knowledge Technology, Nuzvid, Andhra Pradesh, India Sunil Raiyani Civil Engineering Department, Nirma University, Ahmedabad, Gujarat, India ABSTRACT This paper presents the outcome of the experimental program conducted to incorporate the Nano particles in the pervious concrete for the purpose of water purification and improvement in the strength. The Nano particles are small objects that behave as filler for the porosity of concrete, which helps to increase the strength of concrete and maintain the perviousness of concrete. This perviousness of pervious concrete helps to purify the contaminate water also. Three Nano particles Zinc Oxide (ZnO), Charcoal and (MnO 2 ) are used in present experimental program. The quality of the water is checked by the tests such as Hardness test, ph test, turbidity test, Porosity and Permeability test perform to check the inherent property of pervious concrete and compressive strength test performs to check the improvement of Pervious concrete. The result shows charcoal provide good results for water purification and improvement of strength as compare other two Nano particles. Key words: Pervious concrete, Nano Particles, Water purification and Compressive strength. Cite this Article: Bolem Priyanka and Sunil Raiyani. Incorporation of Nano Particles in Pervious Concrete for Water Purification and Strength Improvement. International Journal of Civil Engineering and Technology, 8(4), 2017, pp INTRODUCTION Pervious concrete can be used as a filter media to purify water. It has a void structure to allow the water to pass through it. By incorporating the Nano particles in pervious concrete use to absorb the pollutants from water and try to purify the water and some extent Nano particles help in an improvement of strength of pervious concrete editor@iaeme.com

2 Bolem Priyanka and Sunil Raiyani Francis (1965) reported that the initial use of pervious concrete was started in 1852 in the United Kingdom with the construction of two residential houses and sea groyne [1]. Peterson (1943), Valore and Green (1951) were carried their studies on pervious concrete and specified the size of aggregate as 10mm 4.75mm [2,3]. In 1990, Pratt investigated the efficiency of pervious concrete in retaining the oil contents. He observed that the pervious concrete was retaining maximum oil content in both mechanical and biological treatment [4]. Mathis 1990, studied on reducing uncontrolled storm water runoff and applied pervious concrete for permeable base and edge drains in U.S and other places. Four different pavers were investigated for their retention capability of dissolved heavy metals and those observations revealed that lead and copper were retaining effectively [5]. Later, Ming Ju Lee et al. advanced their investigations on pervious concrete to test the effluent water. Tests were carried on water and the results were not matched with the drinking water standards but the water was purified up to some extent [6]. The study results on pervious concrete as a filter to reduce the salinity of water and noticed that salinity was decreased and ph level also approximately reached to standards and also the 99.6% oil content retained in pervious concrete [7]. However, a research and development is needed to determine the efficiency of Nano particles to improve the water purification performance and strength of concrete. 2. EXPERIMENTAL PROGRAMME To understand the performance of Nano particles in pervious concrete to improve the strength and water purification capability, 38 cylinder specimen of size 150 mm 300 mm were cast. Concrete mix design was done according to ACI 522R 10 [8].Table 1 shows the final mix proportion of constituents. Table 1Mix proportions calculated as per ACI 552R - 10 OPC 53 grade Cement Coarse aggregates* Water content * Size ranged from 10 mm to 4.75 mm [2, 3] Nano particles have great potential as water purification catalysts and redox active media due to their large surface area. Nano particles like Zinc Oxide (Zno), Charcoal and (MnO 2 ) shown in Figure 1 were used for the present study. Each Nano particle dosageis taken as 0.2 %, 0.25 % and 0.3 % of cement content to prepare the cylinder specimen. For compression test total 20 specimens were cast. Out of which 2 control specimen and 18 specimens with Nano particles. For each proportion of Nano particle dosage, two samples were prepared. For assessment of Porosity, Permeability, ph value, Turbidity and Hardness total 18 specimens were prepared. These Cylinder specimens were cast and cured 28 days under laboratory conditions as shown in Figure editor@iaeme.com

3 Incorporation of Nano Particles in Pervious Concrete for Water Purification and Strength Improvement Zinc Oxide (ZnO) Charcoal (MnO 2 ) Figure 1 Nano Particles used for the study Mixing Casting Curing Figure 2 Mixing, Casting and Curing of Pervious concrete 3. EXPERIMENTAL TEST SETUP After 28 days of curing 20 specimens were tested in accordance to IS: [9] with the help of universal testing machine as shown in Figure 3. Out of 20 specimens, 2 are control specimens and remaining 18 specimens are of 0.2%, 0.25% and 0.3% dosage of each ZnO, Charcoal and MnO 2 Nano particles mixed in concrete. The load is applied at a constant interval as specified in IS code up to ultimate load capacity of the cylinder. The ability of concrete to drain water is the key point of pervious concrete. Interconnected voids within the concrete allow the water to drain. While there is an inverse relationship between porosity and compressive strength. To estimate the porosity, there is no set standard for testing the concrete. Flores et al. [10] have devised a testing procedure that evaluates the filtration ability of pervious concrete cores. The test involves measuring the time it takes for a given amount of water to pass from the top of the cylinder to the bottom. To account for bi directional flow, the pervious concrete cylinder was wrapped in a waterproof and nonabsorbent material editor@iaeme.com

4 Bolem Priyanka and Sunil Raiyani Figure 3 Test setup for compression load Schaefer et al. [11] developed another method to measure the permeability of pervious concrete is falling head parameter. The pervious concrete cores are encased in an impermeable no adsorbing membrane and connected to a vertical PVC pipe with one ends on each side, labeled upstream and downstream. To remove the air voids in the pervious concrete, water was filled in the downstream end up until ware reached the top of the concrete core. Water was then filled on the upstream up starting of scale. Equilibrium was allowed to be reached. Water was then added to the upstream side. The time ( t in second) for the water to drop from an initial head ( h 1 ) to final head ( h 2 ) was recorded and permeability can be calculated as per standard falling head formula is given in below equation. Where A and a are cross sectional areas of measuring cylinder and concrete sample respectively. l is the length of the concrete sample. Figure 3 shows the test setup for the falling head permeability. k al log h 2 At h1 Figure 4 Test setup for Falling head permeability editor@iaeme.com

5 Incorporation of Nano Particles in Pervious Concrete for Water Purification and Strength Improvement 4. RESULTS AND DISCUSSION There were two different categories of test performed on cylinder specimen. One is a compressive test and another test on water, which was drained through the pervious concrete cylinder. Comprehensive results are presented here for all the samples Compressive Strength Test Results The 28 days compressive strength results are presented in Figure 5. The specimens with Nano particles are compared with that of control specimens. Compressive Strength (MPa) Zinc Oxide Charcoal Figure 5 Compressive strength tests results at the age of 28 days From the test, it was observed the average compressive strength of two control specimen is MPa. From the figure, it can be observed that for Charcoal and at 0.25 % of dosage show higher strength compare to control specimen. It also observed optimum percentage of dosage is 0.25 % in case charcoal and can be suggested from this study. Zinc Oxide shows the inferior compressive strength compare to other specimens. The compressive strength for Zinc Oxide is decreasing as a percentage of nano particle increases because it may be reacting with fluorides which were present in water while curing. It also shows Nano particles have a capability to adsorb pollutants in water. Some Nano particles have the capacity to increase or decrease the strength. From above observations, Zinc Oxide is not suited to increase the strength Porosity and Permeability Test Results Pervious concrete is meant for purification of water in the present study due to which presence of voids is mandatory in concrete and to check the voids content porosity is a basic test. Normally porosity range in between 15% to 30% and permeability rate range is in between 0.01 to 100 mm/sec as per ACI 522. From the Table 2 observed that all the specimens show nearly same permeability results. Permeability is highly correlated to porosity and since the void ratios varied from 15 to 20 %, the permeability results were also expected fairly same. From the results, it can be concluded Porosity is directly proportional to permeability. All the sample values of porosity are within limit except 0.30% of Charcoal. Here, porosity may get affected by compaction energy while compacting due to which void editor@iaeme.com

6 Bolem Priyanka and Sunil Raiyani content decrease and it may affect the porosity or may be due to clogging of excess charcoal in the void of cylinder specimen. Nano Particles % of Nano Particles Table 2 Compressive strength tests results at the age of 28 days Porosity (%) Permeability rate (mm/sec) Tests on Water Samples Hardness test, ph test and turbidity test were conducted on two different sample of water. One water sample was collected from the canal located near to Nunna village, Andhra Pradesh, India and another sample were taken as portable water Hardness Tests on Water Samples Hardness of canal water and portable water before passing through the sample are 528 ppm and 225 ppm respectively Hardness (ppm) Zinc Oxide Charcoal (a) Hardness of Canal Water Hardness (ppm) Zinc Oxide Charcoal (b) Hardness of Portable water Figure 6 Hardness of Canal water and Portable water after passing through specimen Hardness is caused due to calcium and magnesium salts. As shown in Figure 6 All the Nano particles are contributing in reducing the hardness but in some case, Zinc Oxide is less effective compared with other two Nano particles. As per WHO standards, the maximum limit for the hardness of drinking water is 500ppm. In most of the case, Hardness is not exceeding the 500 ppm except 0.20% dosage of Zinc Oxide. From the results, it is observed that Charcoal is more effective in reducing the hardness of Canal water as well as Portable water editor@iaeme.com

7 Incorporation of Nano Particles in Pervious Concrete for Water Purification and Strength Improvement ph Tests on Water Samples ph of canal water and portable water before passing through concrete matrix are 7.82 and 7.0 respectively. When water was passed through control concrete sample, the ph of the sample increase 12 and 11.5 for canal water and portable water respectively. ph Value ph Value Zinc Oxide Charcoal (a) ph of Canal Water 0.00 Zinc Oxide Charcoal (b) ph of Portable water Figure 7 ph of Canal water and Portable water after passing through specimen By incorporating Nano particles into pervious concrete the ph of both water sample is reducing. For each Nano particle, a value of ph is decreasing with minor variation. For various proportions of Nano particles may reach the standards of drinking water. Charcoal shows the reasonably good result, as the charcoal dosage is 0.25 %. These water is not reaching the WHO standard for drinking water Turbidity Tests on Water Samples The turbidity of canal water and portable water are 35.5 NTU and NTU respectively. All most all the sample failed in this test. Here, turbidity is due to forming of residue in the collected water which is pass through the cylinder sample. For, the collected water is clear i.e no formation of residue. Because it may not react with the cement constituents and water. After, Charcoal is showing good results compare to Zink Oxide. Graphically interpretation is given in Figure editor@iaeme.com

8 Bolem Priyanka and Sunil Raiyani Turbidity (NTU) Zinc Oxide Charcoal (a) Turbidity of Canal Water Turbidity (NTU) Zinc Oxide Charcoal (b) Turbidity of Portable water Figure 8 Turbidity of Canal water and Portable water after passing through specimen 5. CONCLUSION This paper presents the finding of an experimental program conducted to evaluate the compressive strength, porosity, permeability and water purification capability of Nano particles incorporated in pervious concrete. Incorporating the Nano particles in pervious concrete need to increase the strength of the concrete but results show for some dosage and some Nano particles only the compressive strength is at par with control specimen whereas others dosage and Nano particles it shows a decrement in strength. From the results at 0.25% dosage of Charcoal and gives the good agreement with the compressive strength. The compressive strength of cylinder is inversely proportional to porosity &permeability and Permeability is highly correlated to porosity. Since the void ratios varied from 15 to 20 %, the permeability results were also expected fairly same. Except one case of charcoal at 0.3% dosage. It shows very poor permeability rate and porosity due to clogging of excess charcoal in the void of cylinder specimen. But porosity and permeability of all the dosage and all the Nano particles show as per required standard. Hardness test, ph test and turbidity test clearly show that ZnO cannot be used for water purification. For other Nano particles like Charcoal and MnO 2 shows good agreement with required quality of water. Observation revealed that Charcoal with dosage near to 0.25 % can be used for improving water quality and strength of pervious concrete. ACKNOWLEDGEMENTS The authors are thankful to Dunna Krannthi, Yenugula Narasimha Rao, MekalaVenkateswarlu, Ande Sahendra Babu and Lalam Govinda for helping in testing of samples. The scientific investigation presented in this paper was financed by the Rajiv Gandhi University of Knowledge Technology, Nuzvid editor@iaeme.com

9 Incorporation of Nano Particles in Pervious Concrete for Water Purification and Strength Improvement REFERENCES [1] Francis, A.M. Early concrete buildings in Britain. Concrete and Construction Engineering London, 60 (2)1965, pp [2] Petersen, P.H. Properties of a porous concrete of cement and uniform size gravel. Rep. No. BMS96 National Bureau of Standards, Superintendent of Documents, U.S. Govt. Printing Ofc [3] Valore, C.R. Jr., and Green, C.Air replaces sand in no fines concrete. Journal of ACI Proc., 47(10), 1951, pp [4] Pratt,C.J. Permeable pavements for strom water quality enhancement. Urban Strom water Quality Enhancement source control, retrofitting and combined Sewer Technology Proc., ASCE, 1990, pp [5] Mathis, D. E. Permeable bases An update. Portland Cement Association, 8, 1990, pp [6] Ming Ju Lee, Ming Gin Lee, Yishuo Huang and Chia Liang Chiang. Purification study of pervious concrete pavement. International journal of Engineering and Technology,5(5), pp [7] Majersk, G.M..Filtration and life span analysis of a pervious concrete filter. Thesis University of Colorado, Denver, [8] ACI 522R 10, Report on Pervious Concrete (Reapproved 2011), [9] IS: (Reaffirmed 2006), Indian Standard for Method of tests for strength of concrete, Bureau of Indian standard, [10] Flore, J.J., Martinez, B., Uribe, R. Analysis of the Behavior of Filtration vs. Compressive strength ratio in pervious concrete. Pervious concrete symposium Proc., [11] Schaefer, V.R., Wang, K., Suleiman, Kevern, J. Mix Design Development for Pervious Concrete in Cold Weather Climates, Final report. Center of Transportation Research and Education, Iowa State University, February, editor@iaeme.com