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CHAPTER 8. MASONRY
8.1. See Section 8.1.1.
8.3. Percentage of net cross-sectional area = (447 / 960) x 100 = 46.56% < 75%
Therefore, the unit is categorized as hollow.
8.4. Percentage of net cross-sectional area = (0.007/ 0.015) x 100 = 46.67% < 75%
Therefore, the unit is categorized as hollow.
8.5. a. Gross area compressive strength = P/Agross = 51,000/(7.5 x 7.5) = 906.67 psi
8.6. a. Gross volume = 7-5/8″ x 7-5/8″ x 7-5/8″ = 443.322 in3
8.7. a. Gross area compressive strength = P/Agross = 296/(0.190 x 0.190) = 8,199 kN/m2
8.8. Gross area = 0.290 x 0.190 = 0.0551 m2
Net area = 0.250 x 0.150 = 0.0375 m2
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8.9. a. An= Vn/ h = 312.7 in3/ 7.625 in = 41 in2
8.11. a. To reduce the effect of weathering and to limit the amount of shrinkage due to moisture
weight concrete masonry.
2.43.4
WW
dr
29735776
WW
is
Therefore, the absorption does not meet the
ASTM C90 requirement for absorption for
medium weight concrete masonry.
50915435
WW
dr
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8.13. a. Absorption = 100 x [(Ws– Wd) / Wd] = 100 x [(7401 – 6916) / 6916 ] = 7.01%
8.14. a. Absorption = (Ws – Wd) / Wd= (8652 g – 7781 g) / 7781 g = 871 g / 7781 g = 0.112 =
11.2%
8.16. See Section 8.1.2.
8.4)
8.18. See Section 8.2.
8.20. See Section 8.4.