Materials for Civil and Construction Engineers (2nd Edition)
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ISBN: 9781292154411
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Chapter 7, Problem 7.44QP
Three batches of concrete were prepared using the same materials and ingredients, except that they have water-cement ratios of 0.50, 0.55, and 0.60, respectively. The following tests were performed on specimens made of the three batches:
- Compressive strength test on 4″ × 8″ cylinders
- Center-point flexure test on 4″ ″ 4″ × 12″ beams
- Split tension test on 6″ × 12″ cylinders
Three replicates were tested for each test. Table P7.44 shows the average failure loads for the three replicates of each case.
It is required to do the following:
- a. Complete Table P7.44
- b. Using an Excel sheet, plot the relationships between water-cement ratio and compressive strength, modulus of rupture, and tensile strength on the same graph. Label all axes and curves.
- c. Comment on the effect of water-cement ratio on the compressive strength, modulus of rupture, and tensile strength.
TABLE P7.44
w/c Ratio | Compressive Strength Test | Flexure Test | Split Tension Test | |||
Failure Load (kips) | Compressive Strength (ksi) | Failure Load (kips) | Modulus of Rupture (ksi) | Failure Load (kips) | Tensile Strength (ksi) | |
0.50 | 44.4 | 3.6 | 51.6 | |||
0.55 | 30.8 | 2.7 | 47.0 | |||
0.60 | 24.0 | 2.2 | 41.6 |
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Chapter 7 Solutions
Materials for Civil and Construction Engineers (2nd Edition)
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