Engineering, 19.04.2021 16:00 lucypackham9
A minimum compressive strength of at least 4500 psi, after 180 days of curing (aging), is specified for concrete used in a bridge deck project. It is further specified that a water-cement ratio of 0.5, a slump of 3.5 in, and air entrainment of 4% are to be used. To provide a curing protocol that will produce the required compression strength, the concrete should first be moist cured and then cured:
a. In air for 3 days.
b. In air after 7 days.
c. In air after 14 days
d. A compressive strength of at least 4500 psi cannot be attained.
Answers: 3
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A minimum compressive strength of at least 4500 psi, after 180 days of curing (aging), is specified...
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