329
3700.002
NCMA Research and Development Laboratory
Research Investigation of Mason Productivity
Paper
NCMA and ESCSI
1988
i-v and 1-19
N
This report presents the results of research conducted on concrete masonry to determine the effect of such properties as unit size and weight on mason productivity.The investigation was carried out in a controlled environment to avoid the introduction of additional variables which might influence the results and/or render it impossible to duplicate the test conditions at some later date and location.
Four concrete masonry walls were constructed under close supervision using 16″ and 24″ long lightweight and heavyweight units. The original intent was for all four walls to be constructed of the same width. However, due to the inability to locate a source of 6″x8″x24″ heavyweight units, it was decided to construct the two walls consisting of 24″ long units of a different width and bonding pattern of that selected for the 16″ units.
It therefore was possible to make a direct comparison of the productivity rates of only two courses of the walls constructed of 16″ and 24″ long units.
However, direct comparison between the courses of walls constructed of 16″ long lightweight and heavyweight units and the courses of walls constructed of 24″ long lightweight and heavyweight units was possible.
By summing the measured times of all the courses of each wall it can be shown that the production rate of the wall constructed of 16″ long lightweight units exceeds that of the wall constructed of 16″ heavyweight units by approximately 14.7%. In like manner it can be shown that the production rate of the wall constructed of 24″ long lightweight units exceeds that of the wall constructed of 24″ heavyweight units by approximately 18.7%.
Generally speaking, productivity increased as the weight of the units decreased and the length of the units increased.