DanHalen
Well-known member
First let me state that I'm using the All-In-One Civil Engineering PE Breadth & Depth Exam Guide, 2nd Ed. I am reviewing the end of chapter problems and run across a little snag on Prob. 104-003. The problem states:
The table below shows characteristics of a concrete mix. If the total unit weight of the concrete is 142 lb/ft3, what is the air content (percent)?
Component
Weight (lbs)
SG
Volume(ft³)
Cement
450
3.15
2.2894
Sand
870
2.65
5.2612
Stone Aggregate
1106
2.50
*6.0897*
Water
205
1.0
3.2853
Total
2206
16.9256
How do they get 6.0897? When you run the numbers for V = (1106)/(2.50*62.4) = 7.0897 not 6.0897. Is this a typo?
The table below shows characteristics of a concrete mix. If the total unit weight of the concrete is 142 lb/ft3, what is the air content (percent)?
Component
Weight (lbs)
SG
Volume(ft³)
Cement
450
3.15
2.2894
Sand
870
2.65
5.2612
Stone Aggregate
1106
2.50
*6.0897*
Water
205
1.0
3.2853
Total
2206
16.9256
How do they get 6.0897? When you run the numbers for V = (1106)/(2.50*62.4) = 7.0897 not 6.0897. Is this a typo?