ANALYSIS OF THE IMPACT OF ACTIVITY SAMPLING MEASUREMENT ON MASON’S PRODUCTIVITY IN NIGERIAN CONSTRUCTION SITES

Abstract

The dearth of information on activity performance of craftsmen on construction site leads to under-utilization of
labour to the optimum level. The aim of this study is to analyze the impact of activity sampling measurement on
mason‘s productivity in Nigerian construction sites, and the objectives were addressed to determine labour
output and activity time spent by the block laying operatives per day on construction sites. Previous related
literatures were reviewed to identify some of factors influencing production output and related block laying
activities in construction sites. The study employed quantitative technique to conduct the research. 50
construction sites were identified in Abuja using purposive sampling technique, 254 masonry gang operatives
were studied for 150 and 225mm size block wall and at different operational level (substructure and
superstructure). Activity sampling technique adopted for data collection were through observation and
structured time sheet questionnaires designed to record information relating to labour output and time spent on
the activities involved in block laying operation. The activity sampling was grouped based on the level of
commitment into three classes; productive time, contributory time and unproductive time. Descriptive statistics
and percentile were used for determination of mean output and the time spent on per day on the related block
laying activities. The study revealed that standard output of 150mm block laying operation at substructure and
superstructure were 12.91 and 13.30 respectively while 150mm block laying operation at substructure and
superstructure were 9.02 and 10.07 respectively indicating an impact of sizes and locational factor of block
laying on the production output. In a gang of one skilled and one unskilled labour; the skilled labour spent
75.79% on productive, 11.68% on contributory and 11.38% being slothful while the unskilled labour
spent10.85% on productive, 53.94% on contributory and 34.72% being slothful of the 7 hours per day. The
study concludes that activity sampling measurement is an excellent technique to identify slothfulness in
construction site and recommends that activity sampling measurement be adopted as a basis for proportioning
gang size of skilled and unskilled labour.