IMPACT OF MAGNETIZED WATER ON COMPRESSIVE STRENGTH AND DURABILITY OF SANDCRETE BLOCK

Abstract

Cases of collapse of buildings is common in Nigeria due to failure of materials used for the construction and poor design. Sandcrete block is commonly used for the construction of buildings in the country but the sandcrete blocks are normally fragile which demands ways to improve the strength of the sandcrete block. Magnetized water is water that has passed through a magnetic field which enhances proper hydration when it is used for producing sandcrete block and it has the ability to improve the strength of the block. The magnetic water treatment unit was fabricated using a broken permanent magnet from speaker with magnetic flux of 997 Gauss and neodymium magnet rated 1.3 T (1.3 x 104 G), a hose of 25.4 mm diameter, 25.4 mm diameter pipe, 50 litres storage bucket and water control tap. The magnetic treatment unit is 900 mm long with 450 mm hose surrounded by a broken magnet from speaker and a
450 mm long pipe surrounded by 12 pieces ofneodymium magnet. The magnetized water was treated for 11 s (T₁), 33 s (T₂) and 55 s (T₃) but the control was non-magnetized water (T₀). Dangote Portland cement and sand sieved through 4.75 mm were mixed (batching) and the ratio of cement to sand was 1 : 6 by weight and optimum moisture content used for producing the block was 9%. The solid sandcrete block (230 x 100 x 100 mm) was produced using a manually operated moulding block machine. The blocks with 3 replicate for each treatment were cured for 7, 14 and 28 days. After curing for 28 days, the force at peak, compressive strength were determined using Universal Testing Machine of capacity 300 kN (model FT300CT by Testometric Company Limited, United Kingdom). After curing for 28 days, the compressive strength for T₀, T₁, T₂ and T₃ were 2.358, 4.742, 3.406 and 4.903 N/mm2, respectively. The compressive strength for T₁, T₂ and T₃ increased by 7.97 - 18.24, 17 - 39.51 and 44.44 - 107.93% after curing for 7, 14 and 28 days, respectively when compared to T0. Young’s modulus for T1, T2 and T₃ increased by 41.74 – 74.48, 14.33 – 39.01 and 43.28 – 79.02% after curing for 7, 14 and 28 days, respectively. The magnetized water increased the compressive strength of the sandcrete block and is recommended for producing sandcrete blocks in the country.