Masonry Magazine September 1965 Page. 20
weight and volume of units
When Eq Th is known and is expressed in inches, the weight of concrete masonry per sq. ft. of wall area can be calculated as follows: If Wm equals weight of masonry (lbs./sq. ft.), and We equals density of concrete in unit (lbs./cu. ft.), then
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W=Eq Th-Wa
12
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Specific information on density of concrete types and weights of units may be obtained from local manufacturers. In the absence of such specific information, the values expressed for the products following may be assumed:
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Pumice Concrete Cu. ft.
Expanded shale concrete 75 lbs.
Expanded slag and Cinder 85 lbs.
concrete 95 lbs.
Air-cooled slag concrete 120 lbs.
Crushed stone and
gravel concrete 135 lbs.
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Gross and Solid Volumes and Equivalent Solid Thickness of Hollow Stretcher Units
(Data based on units 7% in. high by 15% in, long.)
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| Width, in. | Gross. Volume, cu. in. (cu. ft.) | Minimum Thicknesses | 3-Core Units | 2-Core Units |
|---|---|---|---|---|
| | | Shell, in. | Web, in. | Percent Solid Volume | Equivalent Solid Thickness, in. | Percent Solid Volume | Equivalent Solid Thickness, in. |
| 3% | 432 (0.25) | 0.75 | 0.75 | 63 | 2.28 | 64 | 2.32 |
| | | 1.00 | 1.00 | 73 | 2.66 | 73 | 2.66 |
| 5% | 670 (0.388) | 1.00 | 1.00 | 59 | 3.32 | 57 | 3.21 |
| | | 1.12 | 1.00 | 63 | 3.54 | 61 | 3.43 |
| | | 1.25 | 1.00 | 66 | 3.71 | 64 | 3.60 |
| | | 1.37 | 1.12 | 70 | 3.94 | 68 | 3.82 |
| 7% | 908 (0.526) | 1.25 | 1.00 | 56 | 4.27 | 53 | 4.04 |
| | | 1.37 | 1.12 | 60 | 4.57 | 57 | 4.35 |
| | | 1.50 | 1.12 | 62 | 4.73 | 59 | 4.50 |
| 9% | 1145 (0.664) | 1.25 | 1.12 | 53 | 5.10 | 48 | 4.62 |
| | | 1.37 | 1.12 | 55 | 5.29 | 51 | 4.91 |
| | | 1.50 | 1.25 | 58 | 5.58 | 54 | 5.20 |
| 11% | 1385 (0.803) | 1.25 | 1.12 | 49 | 5.70 | 44 | 5.12 |
| | | 1.37 | 1.12 | 51 | 5.93 | 46 | 5.35 |
| | | 1.50 | 1.25 | 54 | 6.28 | 49 | 5,70 |
| | | 1.75 | 1.25 | 57 | 6.63 | 52 | 6.05 |
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NATIONAL CONCRETE MASONRY ASSOCIATION
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Arlington 1, Virginia