Effect of Pour Size on Concrete Placing Productivity in Nigeria

摘要

Pour size as one of the site factors affecting concreting was examined to determine its effects on concreting productivity. A total of 167 separate concrete pours were observed on 25 building construction sites in Lagos, Nigeria,comprising 35 pours placed by crane and skip; 26 pours placed by dumper; 58 pours placed by wheelbarrow; 37 pours placed by head pan; and 11 pours placed jointly by pump, wheelbarrow and head pan. Data collected from the daily concrete pours were analyzed to determine operational productivity rates. The relationship between concreting productivity and pour size was examined using regression analyses to develop a model relating productivity to pour size. The results showed that irrespective of placing method, productivity generally increased by 1.1 m~3/h for every 10 m~3 increase in pour size. It was recommended that the obtained index of productivity increase per pour size be standardised for use in improving on-site productivity in the Nigerian construction industry.