CONSTRUCTION PRACTICES WITH READY-MIX CONCRETE IN ADDIS ABABA

Ready-mix concrete (RMC) is an important construction material prepared according to a set engineered mix design. The use of RMC has been practiced worldwide starting before a century ago because of a number of its advantages over the traditional in situ mix concrete. A better control over the raw materials while batching & mixing, and faster construction are some of its advantages over in situ mixed concrete. In Ethiopia, construction involving concrete is undertaken mostly using in situ mixed concrete, and the practice of construction with RMC is at a young stage still. However, there has been a significant shifting to the use of RMC in the past few years. Some local and foreign contractors, and real estate developers own concrete batching plants and produce RMC for their consumption. Some contractors, however, purchase RMC from RMC suppliers. This research explored into the practices of, handling, placing, compacting and curing of RMC in Addis Ababa focusing on the concrete supplied from RMC suppliers. It is noted that the practices of handling raw materials, placing concrete, vibration and finishing significantly deviate from what are stipulated in literatures and codes of standards. In general terms, the control over the production process is inefficient.