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ECE 302 Fall 2017
HOMEWORK #4 (SOLUTION)
Due October 23, 2017 (Total 38 points)
MASONRY
HW4-1. A concrete masonry unit is tested for compressive strength and produces the following
results:
• Failure load = 120,000 lb
• Gross = 130 in2
• Gross = 960 in3
• Net = 447 in3
Is the unit categorized as solid or hollow? Why? What is the compressive strength? Does the
compressive strength satisfy the ASTM requirements for load bearing units shown in Table 8.2? (4
pts)
►Solution
Percentage of net cross-sectional area = (0.007/ 0.015) x 100 = 46.67% < 75%
