EFFECT OF NANO-CEMENT IN REDUCING THE VALUE OF ROUGHNESS COEFFICIENT

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 4, April 2018, pp , Article ID: IJCIET_09_04_084 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed EFFECT OF NANO-CEMENT IN REDUCING THE VALUE OF ROUGHNESS COEFFICIENT Estherrani V, Muthukumaran N and Prince Arulraj G Department of Civil Engineering, Karunya Institute of Technology and sciences, Coimbatore, India ABSTRACT Manning s equation is widely used for the determination of velocity and in open channels. By reducing the Manning s coefficient, the can be increased by which an efficient canal can be constructed. Only a few investigations have been carried out to reduce the Manning s coefficient with different canal lining materials. In this research, an attempt has been made to determine the effect of lining tiles with Nano cement in reducing the value of Manning s coefficient. An Experimental investigation was carried out in a tilting flume of size 3000mm x 150mm x 300mm.Linig tiles were made with 1:3 cement. In order to make a smooth surface and to reduce the value of Manning s coefficient, Nano-cement was used to replace cement. Cement was replaced with 10% and 20% of Nano cement and lining tiles were made. These tiles were used as lining material in the tilting flume. The values of Manning s n were determined for three slopes to cover both subcritical and supercritical flow regimes. The variations of n values with respect to depth of flow and Froude s number were found for the cement tile and tiles with 10% and 20% of Nano cement. The n values were compared to determine the effect of Nano cement in reducing the value of Manning s coefficient. From the experimental results, it is found that the Manning s coefficient decreases with the addition of Nano-cement. The due to the reduction in the n value is found to be between 1.44% to 55.99% Keywords: Nano-cement, Manning s coefficient, Discharge. Cite this Article: Estherrani V, Muthukumaran N and Prince Arulraj G, Effect of Nano-Cement in Reducing the Value of Roughness Coefficient, International Journal of Civil Engineering and Technology, 9(4), 2018, pp INTRODUCTION Hydraulics engineering projects are developing rapidly in the recent years. The knowledge of open channel flow is essential for designing any hydraulic structure. In open channel flow, the pressure at the surface is constant and the hydraulic grade line is at the surface of the fluid. The geometric elements of the open channel flows are depth of flow, depth of flow section, top width, water area, wetted perimeter, hydraulic radius, and hydraulic depth editor@iaeme.com

2 Estherrani V, Muthukumaran N and Prince Arulraj G The vegetation of the surface affects the velocity distribution and it acts as an obstacle to the flow of water. Highly flexible low grass, dense bushes plants and trees may cover the surface. They increase the surface roughness and hence increases the Manning s roughness coefficient. The vegetation in the path of the flow will increase the flow resistance, change the sediment transport deposition, and change the backwater profile When compared with the Chezy s formula, the Manning s formula is found to be opted formula for the determination of velocity and flow in open channels. The channel roughness and the flow resistance are represented by the coefficient of roughness and the most widely used formulae in open channel flow is the Manning s equation. The Manning s equation is; V= Where, V is the velocity of the flow, n is the manning s coefficient, s is the slope of the channel, R is the hydraulic radius. The roughness or the friction applied to the flow are determined by the Manning s n coefficient. The channel irregularity, channel alignment, scouring, obstruction, size and shape of the channel, stage and, suspended material, vegetation on the channel are the factors that affect the Manning s coefficient. Many investigations have been carried out, all over the world to determine the appropriate value for Manning s coefficient. The Nano particles fill the pores in the surface of concrete and and hence the roughness is reduced. Nano materials also improve the mechanical properties of and concrete. Hence tiles with Nano particles may be used to reduce the value of surface roughness, so that through the channels can be increased Properties of Nano-Cement The size of normal cement particles size ranges between 50µm and 90µm.The size of Nanocement particles size ranges between few Nano meters and 100nm. The Nano cement particles having high surface area are very active and hence they reduce the setting time, increase the strength and durability of cement. They also make the surface smooth thereby reduce the surface friction Literature Review Lau T.W. et.al carried out an experimental investigation on the effect of roughness on and the factors that affect roughness coefficient. Experiments were carried out using a flume (8m x 0.3m x 0.4m) with different types of bed materials such as 2mm grain size and 5mm grain size. The experiments were carried out with various flow rates for slope equal to 1:300, 1:600 and 1:900 to determine the effect of slopes on roughness coefficient. The 5mm grain size had the highest roughness coefficient when compared with others and it was observed that the Manning roughness coefficient decreased at flatter slope (1:900)(Lau and Afshar,2013 ). Shaoyun Deng carried out an Experimental investigation to determine the effect of silica Nano particles in reducing the Manning s Coefficient. The application of silicate Nanoparticles as a floor coating material of the channels had been investigated and studied in a editor@iaeme.com

3 Effect of Nano-Cement in Reducing the Value of Roughness Coefficient hydraulic flume. Their properties were explained. It was reported that there is a decrease of 16 to 38% in the Manning s coefficient as compared with the normal cement concrete(shaoyun, 2013). Mitra L et.al carried out an experimental investigation and compared the values of Manning s coefficient of original bed material and grass carpet. The roughness coefficient is important to know the flow rate, water level during the flood, for the design of the hydraulic structures. The depth of water, Manning s coefficient, Froude s number were determined by varying three slopes and three s. The Manning s n for grass carpet was very high and the average value was 0.12(Mitra, Mimi and Saikia, 2016). Mitra L and Mimi das saikia carried out an experimental investigation using different bed materials. Grass carpet and PVC were used and compared with the original bed material by varying three flow rates ( m3/sec,000367m3/sec,0.0012m3/sec). It was concluded that the value of Manning s n for original bed material was very high, it was less for the PVC, and minimum for the grass carpet(mitra and Saikia, 2016). Ali et.al carried out an experimental investigation to determine the effect of the roughness of the surface in the channel by conducting experiment in the flume of dimension (10m*0.3m*0.46m). With the smooth surface and the gravel surface the rate of flow and roughness were determined by varying the slope and with different flow rates. The Manning s coefficient was found to be high for the rough surface and low for the smooth surface(saib, Tun and Onn, 2011). Raki L et al reported that the use of the Nano particles in the concrete increases the compressive strength of cement. National Research Council Canada had shown that by modifying the structure of cement hydrates, and addition of nanoparticles increases the potential of the cement. silica. gases. Addition of Nano particle to the concrete improves the micro structure of concrete(raki et al., 2010) Research Gap The materials such as concrete with silica nanoparticles, grass carpet, PVC, steel plate and gravel with varying dimensions were used in the experiments with an objective of reducing the friction of lining materials. But the effect of other Nano materials was not studied. The lining of the materials was used only in the floor but the sides of the channel or the flume were not tried. replacement of cement with Nano materials were not considered for most of the research. In this research an attempt has been made to use the Nano cement for the partial replacement of cement. The tiles were prepared by replacing the cement with 10% and 20% of Nano cement. 2. METHODOLOGY AND MATERIALS PREPARATION 2.1. Methodology Used A tilting flume of size 3000mm*300mm*150mm was used for this investigation. According to the dimensions of the flume, tiles were made and placed inside the flume as a lining material. The tiles were prepared with a mix ratio of 1:3 for the normal cement. The cement Nano particles were prepared using a ball grinding mill. Cement tiles of 1:3 ratio and tiles in which cement was partially replaced with Nano cement were used as a lining material. The Manning s coefficient of cement tile and tiles in which 10% and editor@iaeme.com

4 Estherrani V, Muthukumaran N and Prince Arulraj G 20% of cement was replaced with Nano cement were compared. Experiment was conducted by varying the slope to cover both the subcritical and super critical flow regimes Tile Dimensions For lining the flume, tiles were cast. For lining the bottom of the flume, tiles of size 200*100*20mm were cast with cement and cement with Nano cement particles. For lining the sides of the flume, tiles of size 200*200*20mm were cast. The tiles were cured for 7 days and used for lining. The tiles used are is shown in Fig.1 Figure 1 Tiles for bed and side tiles. 3. EXPERIMENTAL INVESTIGATION 3.1. Description about the Flume A flume is a structure that is used to carry the water above the depression above or below the ground surface. The flume that is used for the experiments is a rectangular flume with glass sides. The size of flume is size 3000mm*300mm*150mm. The slope and the of the flume can be changed. An venturimeter was used find the. Water is pumped to the flume by a one-horse power pump. The flow measured using an orifice meter of diameter m. The view of the flume is shown in Fig.2 Figure 2 Experimental setup (Flume) 3.2. Hydraulic Parameters Considered Flow Velocity Flow velocity depends on the roughness of the surface, obstruction in the bed surface, and slope. When the slope is steep, the velocity will be high. The flow velocity is determined by, editor@iaeme.com

5 Effect of Nano-Cement in Reducing the Value of Roughness Coefficient Where, Q is the, V is the velocity, A is the area of the flume. Manning s Coefficient Manning s coefficient is determined from Manning s equation which is an empirical formula used to determine the velocity and in an open channel flow, when the flow is steady and uniform. V= Discharge Discharge is the amount of water that flows in each cross-sectional area. Discharge was calculated by, Where, Q is the, g is the acceleration due to gravity, h is the head loss, is the area of the pipe, is the area of the orifice. Froude s Number Froude s number is defined as the ratio of the flow inertia to the gravity force. Gravity makes the particle to move downwards and the inertial force resists. The Froude s number is given by, Where, F is the Froude s number, v is the velocity (m/s), D is the hydraulic depth of the flow, g is the acceleration due to gravity. 4. RESULTS AND DISCUSSION The values of Manning s n for different lining materials are given in Table 1,2 and 3 respectively for slope 1(0.262), slope2(0.074), slope3(0.038) for tiles with cement 1:3 and tiles with 10% Nano cement editor@iaeme.com

6 Estherrani V, Muthukumaran N and Prince Arulraj G Table 1 Comparison of Manning s n (Cement and tiles with 10% of Nano cement slope1 (0.262)) number Manning s n of cement Manning s n for tiles with 10% Nano-cement "n" value Table 2 Comparison of Manning s n (Cement and tiles with 10% of Nano cement slope2 (0.074)) Number Manning s n of cement Manning s n for tiles with 10% Nanocement Table 3 Comparison of Manning s n (Cement and tiles with 10% of Nano cement slope3 (0.038)) Number Manning s n of cement Manning s n for tiles with 10% Nano-cement The values of Manning s n for different lining materials are given in Table 4,5 and 6 respectively for slope 1(0.262), slope2(0.074), slope 3(0.038) for tiles with cement 1:3 and tiles with 20% Nano cement. Table 4 Comparison of Manning s n (Cement and tiles with 20% of Nano cement slope1 (0.262)) Number Manning s n of cement Manning s n for tiles with 20% Nano-cement Table 5 Comparison of Manning s n (Cement and tiles with 20% of Nano cement slope 2(0.074)) Number Manning s n of cement Manning s n for tiles with 20% Nano-cement editor@iaeme.com

7 Mannings n Effect of Nano-Cement in Reducing the Value of Roughness Coefficient Table 6 Comparison of Manning s n (Cement and tiles with 20% of Nano cement slope 3(0.038) Number Manning s n of cement Manning s n for tiles with 20% Nanocement From the Tables, it can be seen that the Manning s decreases when cement tiles are replaced with tiles with 10% and 20% of Nano-cement.The Manning s n is found to be between 1.35% to 52.63% The is found to be between 1.44% to 55.99% The variation of Manning s coefficient with respect to number is shown in Fig number vs Manning's n Number Figure 3 Variation of Manning s n with respect to Froude s Number From the Fig.3, it can be seen that Manning s n decreases as Froude s increases. number 5. CONCLUSIONS It is found that Manning s coefficient decreases as the Froude s number increases. The Manning s is found to be more in sub-critical flow and less in supercritical flow. It is found that Manning s coefficient increases as the depth of flow increases. It is found that addition of Nano cement reduces the value of Manning s n. The due to the reduction in the n value is found to be between 1.44% to 55.99%. As the replacement of cement with Nano cement increases, the Manning s coefficient decreases. REFERENCES [1] Lau, T. W., and Afshar N. R.. "Effect of roughness on." UNIMAS e-journal of Civil Engineering 4 (2013): [2] Shao yun, Deng. "Experimental Research on Application of Nano-Concrete to Reduce Roughness Coefficient." Digital Manufacturing and Automation (ICDMA), 2013 Fourth International Conference on. IEEE, editor@iaeme.com

8 Estherrani V, Muthukumaran N and Prince Arulraj G [3] Mitra L, Mimi Saikia D, Analysis of Flow Resistance in Open Channel for Proper Flow Prediction, International Journal of Civil, Mechanical and Energy Science (IJCMES 2016no. 1, pp [4] Mitra L, Mimi Saikai D, Analysis of flow resistance for different bed amterials with varying experimentally in open channels, International journal of Innovative research in science, engineering and technology(ijirset), [5] Md Ali, Zarina and Saib, Nor Ashikin, "Influence of bed roughness in open channel." International seminar on Application of Science and Mathematics (2011). [6] Raki, L., Beaudoin, J., Alizadeh, R., Makar, J., & Sato, T. Cement and concrete nanoscience and nanotechnology. Materials 2010, 3(2), editor@iaeme.com