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Nano Concrete and Its Classified Applications in Nano Technology NANO CONCRETE AND ITS CLASSIFIED APPLICATIONS IN NANO TECHNOLOGY 1ANUPRIYA P. JADHAV, 2A. P. PATIL, 3 D. D. PARKHE, 4S. D. BHAGAT, 5RAJENDRA PAWAR 1,2,3,4,5 MAHARASHTRA ENGINEERING RESEARCH INSTITUTE, NASHIK, MAHARASHTRA, INDIA . Email: [email protected] Abstract - This paper presents a modified design of Nanotechnology, which is one of the most active research areas that include a Number of disciplines including civil engineering and construction materials. In this paper, nano –silica has been replaced in various properties such as 2.5%, 3%, 3.5% to the weight of cement. Then the properties of concrete such as compressive strength of respective specimens were tested after 7 & 28 days of curing. Result has been obtained & compared with normal concrete mix. Nano concrete was concluded to have a higher strength than the ordinary concrete. Nanotechnology is the understanding, control, and restructuring of matter on the order of nano meters (i.e., less than 500nm) to create materials with fundamentally new properties and functions. The main advances have been in the nano science of cementitious materials with an increase in the knowledge and understanding of basic phenomena in cement at the nano scale. Keywords - Nano Scale, Asr, Nano Tube, Nano Silica, Polycarboxylates, Atomic Scale, Nano Concrete. I. INTRODUCTION C. WHAT IS NANO CONCRETE? A concrete made with portland cement particles that A. GNERAL are less than 500nm as a cementing agent. Nano Nanotechnology encompasses main approaches: (i) concrete is concrete made by filling the pores in the top down” approach, in which larger structures are conventional concrte using nano particals of size less reduced in size to the nano scale while maintaining than 500 nm.Currently cement particle sizes range their original properties order constructed from larger from a few nano-meters to a maximum of about 100 structures in to their smaller, composite parts and (ii) micro meters. the bottom-up” approach, also called molecular nano Nano technology generated products have unique technology” or molecular manufacturing,” in which characteristics, and can significantly fix current materials are engineered from atoms or molecular construction problems, and may change their components through a process of assembly or organization of construction process. The recent self-Traditionally nano technology has been developments in the study and manipulation of concerned with developments in the fields of micro materials and processes at the nano scale offer the electronics, medicine and material sciences. However great prospect of producing new macro materials, the potential for applications of many developments in properties and products. Exploitation of nano the nanotechnology field in the area of construction technology in concrete on a commercial scale remains engineering is growing. limited with few results successfully converted in to In this study nano silica has added in various marketable products. properties such as 2.5%, 3%, 3.5% to the weight of cement. The Compressive strength of respective II. OBJECTIVES specimens were tested after 7 & 28 days of curing. Then obtained results compared with traditional a) To achieve the desired compressive strength in concrete. Addition of nano silica in concrete improves concrete. the properties of materials which results densifying the b) To elaborate the study over nano technology field. nano structures. Thus nano particals act as a filler of c) To focus on effects of nano concrete on other pores in concrete which influences the results. materials. d) To focus on effects of nano concrete on B. WHY NANOTECHNOLOGY FOR environment health etc. CONCRETE? e) To analyse the economic difference of nano a) Improves the materials’ bulk properties. concrete and ordinary routine concrete. b) Ability to control or manipulate materials at the f) To elaborate study over the types of nano atomic scale. Nano scale attack on ASR (Alkali concrete. Silicate Reaction) c) To obtain thinner final products and faster setting III. LITERATURE REVIEW time. d) It is having cost effectiveness. 1. R. Sakthivel Research Scholar Karpagam e) Lowered levels of environmental contamination. University, Coimbatore studied he influence of Nano-Silica on various properties of concrete is Proceedings of IRAJ International Conference, 28th October 2018, Pune, India 8 Nano Concrete and its Classified Applications in Nano Technology obtained by replacing the cement with various silica, durability and strength performance is percentages of Nano-Silica. Nano-Silica is used increased than conventional concrete. as a partial replacement for cement in the range of 2.5%, 3%, and 3.5% for M25 mix. Specimens are IV. NANO MATERIALS casted using Nano-Silica concrete. Laboratory tests were conducted to determine the Following are the nano matrials which are used in compressive strength, split tensile and flexural concrete to improves the nano structures. strength of Nano-Silica concrete at the age of 7 1. Carbon Nanotubes. and 28 days. Results indicate that the concrete, by 2. Nano-silica. using Nano-Silica powder, was able to increase its 3. Polycarboxylates. compressive strength. However, the density is reduced compared to standard mix of concrete. 1. Carbon Nanotubes- Carbon nanotubes are The replacement of cement with 3% Nano-Silica molecular-scale tubes of graphitic carbon with results in higher strength and reduction in the outstanding properties. They can be several permeability than the controlled concrete. The millimeters in length and can have one “layer” or wall replacement of cement with Nano-Silica more (single walled nanotube) or more than one wall (multi than 3% results in the reduction of various walled nanotube). properties of Nano-Silica concrete. 2. P.Vasanthi and S .Senthilselvan said the use of nano materials in concrete is gaining increasing attention in the construction industry. Studies have shown that concrete containing nano particles has demonstrated increased strength, durability and reduction of pores in the concrete due to the pore filling properties of the nano materials. This also results in increased resistance to corrosion of the steel reinforcements. Hence, the nano materials are useful to improve the life of the building. The use of large quantity of cement produces increasing CO2 emissions and also consequents the greenhouse effect. The nano materials are used in order to reduce the cement content in the concrete mix. Nano material represents one of the most outstanding advances Properties of carbon nano tube- in concrete technology during the last decade. Due to its specific properties, nano materials may CNT are also highly flexible. constitute the significant improvement of the Mechanically, CNT appear to be the strongest quality of the concrete structure and open up new material. fields for the application of concrete. Nano The smaller diameters. material is spread all over the world with a steady Stiffest and strongest fibers. increase in number of applications. Nano materials are intentionally produced and designed 2. Nano-silica- It is the first nano product that with very specific properties related to shape, size replaced the micro silica. Advancement made by the and surface properties. The main use of nano study of concrete at nano scale have proved nano silica materials in concrete is to increase the strength. much better than silica used in conventional concrete. Nano Silica produces high compressive strength concrete. It also provides high workability with reduced water cement ratio. 3. Mani M. and Dr. G. Nandini Devi studied over nano technology and said it is one of most active research areas which have wide application in all construction fields. In this paper, a study is carried out about Nano materials used like nano silica, nanoTio2, and carbon nanotubes which are less than 500 nano meter. Nano silica has heat transfer. Nano Tio2 also has heat transfer and UV absorption character. By the addition of nano Proceedings of IRAJ International Conference, 28th October 2018, Pune, India 9 Nano Concrete and its Classified Applications in Nano Technology Properties of nanosilica- Fine aggregate = 794 Kg/m3 Coarse aggregate = 1204 Kg/m3 It increases strength and durability of concrete. Water-cement ratio = 0.45 High workability with reduced water/cement ratio. Water content = 140 Kg/m3 Use of super plasticizing additives is unnecessary. C: FA: CA = 1:1.52:2.75 Fills up all the micro pores and micro spaces. The mix proportion for M25 concrete is calculated using IS 456:2000, IS 10262:2009. Superplastisizer is 3. Polycarboxylates- Polycarboxylates or polymer also added to increase the workability of concrete. based concrete admixtures are High Range Water Reducing admixture (HRWR).Low dosage-reduce Test Specimens: water as much as high dosage of conventional admixtures. Higher dosage-produce Self Compacting The compressive stress of normal concrete & nano Concrete (SCC). This admixture type is very suitable concrete are determined by casting cubes of size for underwater anti-washout concrete. 150x150x150 mm allowed for 7 and 28 days curing and the test results have been obtained and compared with normal concrete. Compressive Compressive Specimen stress in 7 days stress in 28 days (N/mm2 ) (N/mm2 ) CC 18.99 27.60 NS 2.5% 25.95 29.15 NS 3% 27.75 34.50 NS 3.5% 26.66 32.50 Table 2: compressive stress of controlled concrete cubes and Properties of Polycarboxylates- Nano silica cube Resistance to compression - 40 to 90MPa in 1 day. Resistance to compression from 70 a 100 MPa (or more) in 28 days. Produces high resistance even with low addition (1 to 1.5 % of the cements weight) and gives self compacting characteristics with higher proportions (2.5 %). V. EXPERIMENTAL WORKS The nano silica used in making of nano concrete by partial replacement of cement in various properties such as 2.5%, 3%,3.5% and to study the properties of it. Then compared with normal concrte. The preliminary tests were conducted on cement, fine Figure: shows the compressive stress of cubes aggregate, coarse aggregate and the test results were Note: CC- controlled concrete, NS- Nano silica obtained.
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