PRODUCTION OF RAPID HARDENING CONCRETE USING LOCAL AGGREGATE AND SODIUM CHLORIDE AS PARTIAL REPLACEMENT OF CEMENT
Ordinary Portland cement (OPC) often lead to slow strength development and construction delays. This study explores the use of rapid-hardening concrete enhanced with sodium chloride (NaCl) to accelerate early strength gain. The use of locally sourced materials, including river sand, Bama gravel, and crushed stone, were used in mix designs guided by BS 8500 and conventional methods using Microsoft Excel spreadsheet. The study used a total of 90 standard concrete cubes (150 mm x150 mm x150 mm) were cast using a mix ratio of 1:0.63:0.09:0.95 and a water�cement ratio of 0.30, with NaCl incorporated at 1�4% as a partial cement replacement. Aggregate tests confirmed compliance with standard specifications. The research results showed that NaCl increased consistency, reduced setting time, and significantly enhanced early compressive strength; achieving 33.23 N/mm� at 1 day and 57.67 N/mm� at 28 days with 4% NaCl. The ratio of destructive to non-destructive strength test results ranged from 1.14 to 1.18 across NaCl dosages. The mix demonstrates strong potential for applications in cold-weather concreting, hydraulic structures, and precast elements requiring early strength. However, due to the risk of chloride-induced corrosion, especially in small-diameter tendons, its use in prestressed concrete is not advised.
Authors : Kadai, B., Onundi, L.O. and Is�haq, M.I.
Category : Open Access Volume (Issue) : 11(1) Date Uploaded : 7th May 2025