EXPERIMENTAL INVESTIGATION ON HIGH PERFORMANCE NANO CONCRETE

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1 International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 7, July 2018, pp , Article ID: IJCIET_09_07_063 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed EXPERIMENTAL INVESTIGATION ON HIGH PERFORMANCE NANO CONCRETE Rashmi. R PhD Scholar, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu Dr.Padma Priya R Associate Professor, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu ABSTRACT This paper investigates the effect of different amount Nano Silica on the mechanical and durability of High Performance Concrete. Nano concrete is a new generation concrete formed of material of Nano scale grain. Nano Silica with weighted percentage of 1, 2, 3, 4% where incorporated in mix design of M40 grade concrete. Initially the physical properties of the concrete were investigated. Almost 260 cubes where casted for different trial mixes for which the compressive strength, tensile strength, Modulus of Elasticity, Sulphate attack, Acid attack, Alkalinity, Rapid Chloride penetration and Water absorption tests were carried out. Finally, the optimum percentage had shown a considerable increase in the mechanical properties and also in Durability aspect. Application of Nano technology is an effective way to increase the strength of concrete, also to improve the durability of concrete and to reduce environmental pollution. Key words: Nano Silica, Compressive Strength, Split Tensile Strength, Durability. Cite this Article: Rashmi. R and Dr.Padma Priya R, Experimental Investigation On High Performance Nano Concrete, International Journal of Civil Engineering and Technology, 9(7), 2018, pp INTRODUCTION Nanotechnology is the recent boom in the emerging field of science and Engineering related to the understanding and control of matter at the nanoscale, i.e., at dimensions between approximately 1 and 100 nm. Concrete, the most ubiquitous material in the world, is a nanostructure, multiphase, composite material that ages over time. The increased demand in the use of high performance concrete in the field of construction engineering has been developed recently. An innovative eco-friendly material is sought in order to obtain higher performance concrete. The High-performance concrete is those concrete which exhibit a good workability, homogeneousness, strength, durability, and stability. This led to the invention of high strength editor@iaeme.com

2 Experimental Investigation On High Performance Nano Concrete and high- performance concrete, by incorporating various other pozzolanic materials into conventional concrete. However, there are many areas where concrete should be improved for better performance of the infrastructure like higher tensile strength, reduced brittleness, increased toughness and higher durability. Nanoscale particles are not new invention in either nature or science. Recent developments in visualization and measurement for characterizing and testing materials at the nanoscale have led to an explosion in nanotechnology-based materials in areas such as polymers, plastics, electronics, car manufacturing, and medicine. Working at the nanoscale enabled the scientists to invent a new material with unique physical, chemical, mechanical, and optical properties of materials. Nanotechnology has two main approaches: (a) the top down approach in which larger structures are reduced in size to the nanoscale while maintaining their original properties (b) the bottom-up approach, also called molecular nanotechnology or molecular manufacturing in which materials are engineered from atoms or molecular components through a process of assembly or selfreducing. The mechanical behaviour of concrete depends to a great extent on structural elements and phenomena that are effective on a micro- and nanoscale. The size of the calcium silicate hydrate (C-S-H) phase which is few nanometre range, is the primarily responsible for strength and other properties in cementatios systems. 2. OBJECTIVE The primary objective of the project is to study the Mechanical property and the Durability of Nano- silica on high strength concrete. Besides, we do emphasis to control or improve materials properties at nano-size level and to compare the conventional concrete with nano-silica concrete from the deciphered information reveal from the experimental study Coarse Aggregate (C.A) The coarse aggregate of 20mm size and specific gravity of 2.86 confirming to IS was used. 3. MATERIALS USED 3.1. Cement OPC 43 grade was used. The physical properties were determined in the laboratory. The cement satisfies the requirements of IS: specifications Aggregate Table 1 Properties Cement Sl no Characteristics Value 1 Type OPC 43 2 Specific gravity Normal 32% 4 Setting Time Fine Aggregate (F.A) The fine aggregate was used in the experiments were conforming to IS: specifications editor@iaeme.com

3 Rashmi. R and Dr.Padma Priya R Table 2 Properties Fine Aggregate Sl no Characteristics Value 1 Type Uncrushed(natural) 2 Specific gravity Total Water Fineness modulus Grading zone III Coarse Aggregate (C.A) The coarse aggregate of 20mm size and specific gravity of 2.86 confirming to IS was used. Table 3 Properties of coarse aggregate Sl no Characteristics Value 1 Type Crushed 2 Maximum size 20mm 3 Specific gravity Total Water absorption 3.645% 5 Fineness modulus Super plasticizer Polycarboxylic Ether is used as super plasticizer. It s an admixture of a new generation to reduce the water to cement ratio, without affecting the workability of the material. Figure 1 Super Plasticiser Table 4 Properties of super plasticizer Sl no Characteristics Value 1 Type Uncrushed(natural) 2 Specific gravity Total Water Absorption editor@iaeme.com

4 Experimental Investigation On High Performance Nano Concrete 3.3. Nano Silica-Amorphous Silicon Dioxide: Silicon dioxide nanoparticles, also known as silica nanoparticles or nanosilica, are the basis for a great deal of biomedical research due to their stability, low toxicity and ability to be functionalized with a range of molecules and polymers. Nano-silica particles are of two types i.e. P-type and S-type according to their structure. The characteristics of P-type particles are that it has numerous nano pores having a pore rate of 0.61 ml/g. The S-type particles comparatively have a smaller surface area. The P-type nanosilica particles exhibit a higher ultraviolet reflectivity when compared to the S-type. Table 5 Properties of super plasticizer Sl no Characteristics Value 1 Type powdered 2 ph Size of particle 10-40nm 4. EXPERIMENTAL WORK AND INVESTIGATION Experimental work was conducted to determine the mechanical properties like compressive strength, tensile strength was carried out. Also, to determine the durability tests like Acid attack test, Sulphate attack test,rapid Chloride Penetration Test, Water Absorption Test, Alkalinity tests were conduted.m40 grade of concrete with partial replacement of Ordinary Portland cement(43 Grade) with Nano silica of various percentage (1%,2%,3%,4% and 5%).The optimum percentage of Nano silica was found to 4%.Only the optimum Nano silica 4% concrete was used to determine the durability property and compared with the conventional concrete. Figure 2 Casted Cubes 4.1. Mix proportion Mix design for M4o grade of concrete is done with water cement ratio as 0.35 as per the standards confining to IS Table 6 Mix proportion Cement Fine Aggregate Coarse Aggregate Water editor@iaeme.com

5 Rashmi. R and Dr.Padma Priya R 4.2. Compressive Strength To determine the optimum percentage of nano silica for M40 grade concrete, various trial mixes were conducted by partially replacing cement with (1,2,3,4,5%) of NS.Cubes of 15X15X15 cm were casted, Cured by immersing in water for 28 days. Compressive strength for 3 days,7 days,28 day were found and the results obtained are represented in the graphical format. Figure 3 Tested Specimen for Compressive Strength Figure 4 Comparison Chart of Compressive Strength 4.3. Split Tensile Strength Split tensile strength of concrete is done as per IS The test was conducted on universal testing machine as shown in fig 3. The split tensile strength is determine for the various Nano silica incorporated concrete and Conventional concrete and represented in the chart below. Figure 5 Tested Specimen for Tensile Strength editor@iaeme.com

6 Experimental Investigation On High Performance Nano Concrete Figure 6 Comparison Chart of Split tensile Strength 4.4. Acid Attack Test The cubes of size 100mm 100mm 100mm are casted and kept under moderate temperature of 270 for 24 hours and then the demould specimens were cured in water for 28 days. After 28 days curing, the specimens were taken out and dried for a day. Initial weights of the cubes were measured. For acid attack, 3% of sulphuric acid (H2SO4) by volume of the water with ph value of about 2 was used. The cubes are cured in the above prepared solution for a period of 30 & 40 days. The cured specimen is of concrete material with E-waste is possible and it also take scare of the disposal problem of E-waste Sulphate Attack Test The cubes of size 100mm 100mm 100mm are casted and kept under moderate temperature of 270 for 24 hours and then the demould specimens were cured in water for 28 days. After 28 days curing, the specimens were taken out and dried for a day. Initial weights of the cubes were measured. For acid attack, 5% of Sodium Sulphate (Na2SO4) by volume of the water with ph value of about 2 was used. The cubes are cured in the above prepared solution for a period of 30 & 40 days. The cured specimen is surface cleaned and weighed then tested in the compression testing machine as per IS Figure 7 Acid Attack Test Specimen editor@iaeme.com

7 Rashmi. R and Dr.Padma Priya R Figure 8 Test Result on Acid Attack Therefore from this study it is found that replacement of concrete material with E-waste is possible and it also take scare of the disposal problem of E-waste Sulphate Attack Test The cubes of size 100mm 100mm 100mm are casted and kept under moderate temperature of 270 for 24 hours and then the demould specimens were cured in water for 28 days. After 28 days curing, the specimens were taken out and dried for a day. Initial weights of the cubes were measured. For acid attack, 5% o fsodium Sulphate (Na2SO4) by volume of the water with ph value of about 2 was used. The cubes are cured in the above prepared solution for a period of 30 & 40 days. The cured specimen is surface cleaned and weighed then tested in the compression testing machine as per IS Figure 9 Sulphate Attack Test Specimen Figure 10 Test Result on Sulphate Attack editor@iaeme.com

8 Experimental Investigation On High Performance Nano Concrete 4.5. Rapid Chloride Penetration Test Concrete disc specimens of size 100mm diameter and 50mm thick were casted After 24 hours, the disc specimens were removed from the mould and cured for 90 days in chloride free distilled water. After curing, the specimens were tested for chloride permeability. Then the specimens were dried free of moisture before testing. The test set up is rapid chloride permeability test (RCPT) assembly and are subjected a voltage of 60v. Figure 11 RCPT Set up Table 7 RCPT Results Cube Specimen Penetration Charge Passed CC VERY LOW NSC VERY LOW Figure 9 Sulphate Attack Test Specimen 4.6. Water Absorption Test According to ASTMC , water absorption test was performed on control and Nano silica Concrete Cubes of size 100mm 100mm 100 mm was tested after 28 days of curing. The specimens is oven dried at a temperature of 100 C to 110 C for not less than 24 hours. Then the specimen removed from the oven was allowed to cool in dry air at a temperature of 20 C to 25 C and the dry weight was found. Then the specimens were immersed in water. The editor@iaeme.com

9 Rashmi. R and Dr.Padma Priya R wet weights were recorded for every ½ hour for 2½ hours, every 1 hour for 4 hours, 24 hr and 72 hr 4.5. Rapid Chloride Penetration Test Concrete disc specimens of size 100mm diameter and 50mm thick were casted After 24 hours, the disc specimens were removed from the mould and cured for 90 days in chloride free distilled water. After curing, the specimens were tested for chloride permeability. Then the specimens were dried free of moisture before testing. The test set up is rapid chloride permeability test (RCPT) assembly and are subjected a voltage of 60v. Figure 10 RCPT Set up Table 8 Water Absorption Test Results 1440 Cube 30 mins 60 mins 120 mins mins CC NSC Alkalinity of Concrete Sample of 20gms powder of crushed concrete of 28 days and 56 day were collected and mixed with 100ml distilled water. The solution was kept for 72 hours. The ph meter was used to and the results are tabulated. Figure 11 Alkalinity Test Set up editor@iaeme.com

10 Experimental Investigation On High Performance Nano Concrete Cube Specimen Table 9 Alkalinity Test Results 28 days ph 56 Days ph CC NSC CONCLUSIONS Based on the experiments conducted following conclusions have been made. There is an overall increase in mechanical properties of the concrete y incorporating Nano-silica appreciably. The optimised percentage found to be 4%. Nano Silica incorporated concrete. The compressive strength Increase on addition 4% of NS. The strength was found to be 47.2% higher than the controlled concrete. The Split Tensile Strength is 47.9% vhigher than the CC From acid resistance test, Nano specimens showed higher resistance to acid attack than controlled concrete. The Strength Nano silica concrete was reduced to 14.67% on the 30th day and 20% on 40th day whereas in CC showed a strength reduction of 11.67% on 30th day and 28% reduction on 40th day Nano silica replaced specimens showed higher resistance to sulphate attack than controlled specimens. The compressive strength of control specimens reduced 12.18% at 30 days and 25% at 40 days where as the compressive strength of Nano silica concrete specimen reduced to 8.6% at 30 Days and 16.35% at 40 Days. The charge passed through Nano silica concrete has showed slightly higher values than control concrete but within the limits. As such, it is indicating lesser permeability of nano silica concrete than compared with controlled concrete The ph value of controlled concrete is higher than the NS concrete specimens. The alkalinity value of Controlled specimen is 9% higher than Nano silica Specimen concrete. REFERENCES [1] Sanchez F. and Sobolev K., Nano Technology in concretea review, Constr. Build Mater, Vol.24, pp (2010). [2] Bjornstrom J., Martinelli A., Matic A., Borjesson L. and I.Panas, Accelerating effects of colloidal nano- silica for beneficial calcium silicate hydrate formation in cement, Chemical Physics Letters, Vol.392 (1), pp (2004). [3] Ji T., Preliminary study on the water permeability and microstructure of concrete incorporating nano-sio2, Cem.and Con. Res., Vol.35 (10), pp (2005). [4] Ye Qing, Zenan Z., Deyu K. and Ch. Rongshen, Influence of nano-sio2 addition on properties of hardened cement paste as compared with silica fume, Constr. Build Mater., Vol.21, pp (2007). [5] Gaitero J.J., Campillo I. and Guerrero A., Reduction of the calcium leaching rate of cement paste by addition of silica-nano particles, Cem.and Con. Res., Vol.38, pp (2008). [6] Mohamed Heikal, S. Abd el Aleem, W.M. Morsi, Characteristics of blended cements containing nanosilica, HBRC Jl., Vol.9 (3), pp (2013) editor@iaeme.com

11 Rashmi. R and Dr.Padma Priya R [7] Lin K.L., Chang W.C., Lin D.F., Luo H.L and Tsai M.C, Effects of nano-sio2 and different ash particle sizes on sludge ash cement mortar, Jl. of Environ. Manage, Vol.88, pp (2008). [8] Li G., Properties of high-volume fly ash concrete incorporating nano-sio2, Cem.and Con. Res., Vol.34, pp (2004). [9] Lin D.F., Lin K.L., Chang W.C., Luo H.L and Cai M.Q, Improvements of nano SiO2 on sludge/fly ash mortar, Waste Management, Vol.28(6),pp (2008). [10] Nazari A. and Riahia S., Splitting tensile strength of concrete using ground granulated blast furnace slag and SiO nanoparticles as binder, Energy and Buildings, Vol.43(4),pp (2011). [11] R. Sakthivel and Dr. N. Balasundaram. Experimental Investigation on Behaviour of Nano Concrete, International Journal of Civil Engineering and Technology, 7(2), 2016, pp [12] Byung Wan Jo, Chang Hyun Kim, and Jae Hoon Lim, Investigations on the Development of Powder Concrete with Nano-SiO Particles, KSCE Journal, Vol.11 (1), pp.37-42(2007). [13] Jo Byung-Wan, Kim Chang-Hyun, and Lim Jae- Hoon, Characteristics of cement mortar with nano- SiO2 particles, ACI Mat. Jl., Vol.104 (4) editor@iaeme.com