International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 01 | Jan 2020 www.irjet.net p-ISSN: 2395-0072 © 2020, IRJET | Impact Factor value: 7.34 | ISO 9001:2008 Certified Journal | Page 106 Effect of Salt Water on Compressive Strength, Flexural Strength and Durability of a Concrete Dr. Amit Vishwakarma 1 , Anubhav Rai 2 , Abhishek Patel 3 1 Associate Professor, Department of civil Engineering, UIT R.G.P.V Bhopal M.P. India 2 Asst Prof. Department of Civil Engineering, G.G.I.T.S, Jabalpur M.P. India 3 Student, Department of Civil Engineering, G.G.I.T.S, Jabalpur M.P. India ---------------------------------------------------------------------***---------------------------------------------------------------------- Abstract - In this thesis the study of compressive strength , flexural strength and durability of concrete and cement mortar cast and cured with Potable water, cast and cured with salt water is carried out. The present study is carried out in 2 phases .In first phase concrete cubes, concrete beam and mortar cubes cast and cured with Potable water for M30 grade and 1:3 cement mortar . In second phase concrete cubes, concrete beam and mortar cubes cast and cured with salt water M30 grade and 1:3 cement mortar For calculation purpose M-30 grade of concrete has been designed on basis of IS code 10262-2009 , by casting and curing of concrete using salt water in severe condition in grade M-30 of concrete. The mix design ratio for M-30 grade is - .45:1:1.84:3.39 (Cement = 363.16 kg/cu.m Water = 186.264 kg /cu.m, Fine aggregates (sand) = 669.683 kg /cu.m, Coarse aggregates = 1230.677 kg /cu.m ) in which Water cement ratio = 0.45 similarly cement mortar (1:3) cubes were also prepared. For Compressive strength test of concrete 18 cubes were casted of size 150mm x 150mm x 150mm for 7, 14, and 28days. For flexural strength test 18 beams were casted of size 150mm x 150mm x 700mm for 7, 14, and 28 days. For Compressive strength test of cement mortar 18 cubes were casted of size 70.5mm x 70.5mm x 70.5mm for 3, 7, and 28days cubes of mortar. To find out the durability of concrete, carbonation depth test is also performed. The test for compressive strength flexural strength and durability has been done and results are shown in graph. Graphs are plotted between flexural strength, compressive strength and durability. The result obtained from this research has shown that compressive strength, flexural strength increases with the use of salt water and durability of concrete decreases. Key Words: Compressive strength, Flexural strength, Durability, salt water, Potable water. 1. INTRODUCTION This Cement concrete and mortar are the most widely used man made construction materials. It is difficult to find out another material of construction which is as versatile as concrete. The versatility of concrete is due to the fact that from the common ingredients, namely cement, aggregates, water and admixtures (sometimes), it is possible to achieve the properties of concrete so as to meet the demand of any particular situation. Water is an significant element of concrete as it actively participates in the chemical reaction with cement. Since it helps to form the strength giving cement gel, the quantity and quality of water is required to be looked very carefully. Compared to other ingredients the quality of water usually receives less attention. Since the strength of concrete is affected by the quality of water, therefore it is necessary to go in to the purity and quality of water. Potable water is generally considered satisfactory for making concrete. This does not appear to be a true statement for all condition. Some waters containing a small amount of sugar would be suitable for drinking but not for making concrete. As per IS 456:2000 water used for mixing and curing shall be clean and free from injurious amounts of oils, acids, alkalis, salts, sugar, organic materials or other substances that may be deleterious to concrete and steel. The permissible limit of chloride (as C) is specified as 2000 mg/l for concrete not containing embedded steel and 500 mg/l for reinforced concrete work. 1.1 SALT WATER Water is one of the important ingredients in making concrete. It was estimated that world’s fresh water bodies is only 2.5 percent and balance constitutes sea water. UN predicted 5billion people will be in short of drinking water. Day by day the water levels are in depleting trend due to its abnormal usage and other environmental effects. A popular yard-stick to the suitability of water for mixing of concrete is that if water is fit for drinking it is fit for making concrete. Due to storage of water, it is warranted to explore various alternative means to Potable water in the construction industry. Lot of marine infrastructure is going to establish along the coast, where sea water is available at least cost. The structures built in marine environment are directly in contact with sea water. Sea water, as its abundant availability along the coastal regions may be adopted for construction both for mixing and curing of concrete as a replacement to Potable water. According to IS 456:2000, mixing or curing of concrete with sea water is not recommended because of presence of harmful salts. Under inevitable situation sea water may be used for mixing or curing in plain concrete with no embedded steel after having given due consideration