Masonry Magazine June 1989 Page. 10
Lightweight
Nominal Size: Weight: Net Vol. Unit Wt.: Weight: Heavyweight Net Vol. Unit Wt.
(in.) (lbs.) (cu. ft.) (pcf) (lbs.) (cu. ft.) (pcf)
4×8×16 17.0 0.19 88.9 24.3 0.19 130.1
6×8×16 19.1 0.23 84.1 32.6 0.25 129.7
8×8×16 25.3 0.28 90.5 34.3 0.27 128.1
12×8×16 35.6 0.40 89.0 48.4 0.38 126.6
4×8×24 26.1 0.28 93.9 36.6 0.27 133.8
8x8x24 46.4 0.46 101.6 52.9 0.40 131.8
Calculated Values
3.2 Mortar
The mortar used was an extended life plastic (ready mixed) mortar, selected on the basis of easily controllable consistency and delivered to the site pre-mixed, thus eliminating any variables which might be introduced during batching and mixing at the job site.
It was delivered and maintained at a cone penetrometer reading of 51 mm 5 mm. Variations in consistency were dictated by the mason: higher cone readings for lighter units and lower cone readings for heavier units.
4.0 Mason Profile
The mason selected for this program is employed in the metropolitan Washington, D.C. area where he doubles as a foreman and line mason.
He is of medium height (5'10") and weight (165 lbs.) and slightly below the estimated average age for masons in the United States (43 years as compared to 53 years on the national average).
The mason professed to being of average speed, which is desirable for the purposes of this investigation.
5.0 Layout of Test Walls
Timed portions of the test walls were designed to measure 28'-0%" in length and provide 18.78 sq. ft. of wall area per course. Courses consisted of single units and multiple units of various widths. (See Figures 5.0-1 and 5.0-2).
Walls constructed using 16" long units consisted of 21 units per course, while walls constructed using 24" long units consisted of 14 units per course (timed length).
Masonry leads were not built; instead, pre-built guides were provided from which to pull the lines. The guides were located outside the length limits of the test walls and units of proper size and length were placed at each end to provide a closure for each course and insure that the proper wall length (28'-0%") was maintained.
6.0 Wall Construction Procedures
The order in which the test walls were to be built was determined by a blind draw. The construction was as follows:
1st Day (10/27/87): Walls consisting of 16" long heavyweight units
12
4
8
12
8
4
66
TIMED LENGTH 28'-03/8" (21 UNITS)
At
12
FIGURE 5.0-1 LAYOUT OF WALLS CONSTRUCTED OF 16" LONG CONCRETE MASONRY UNITS
A-A
8
8
8
TIMED LENGTH 28-0 3/8" (14 UNITS)
B
B-
8
FIGURE 5.0-2 LAYOUT OF WALLS CONSTRUCTED OF 24" LONG CONCRETE MASONRY UNITS
B-B
10 MASONRY-MAY/JUNE, 1989
Guide
Guide