Concrete ultimate strength at one year reaches approximately what percentage of its 28-day strength_______________?
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Answer: C. 20 to 25% more
Explanation
Concrete compressive strength continues increasing well beyond twenty eight days due to ongoing internal cement hydration reactions. Long term strength gain typically adds twenty to twenty five percent more strength compared to standard twenty eight day values. Chemical hydration of unhydrated cement particles proceeds slowly over many months in moist curing environments. Standard concrete strength is conventionally referenced at twenty eight days for quality control and structural design purposes. Hydration is the chemical reaction between cement compounds and water that develops the rigid crystalline binding matrix. Proper moisture and temperature curing conditions are essential for concrete to achieve its maximum potential long term strength.
Lower percentage increases fail to account for the substantial hydration progress that occurs between one month and one year. Extremely high percentage increases exceeding fifty percent are unrealistic for normal Portland cement concretes under standard curing environments. Estimates suggesting strength remains static after twenty eight days ignore well documented long term materials science research findings.
- Subject
- Engineering
- Category
- Civil Engineering
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- —
- Difficulty
- medium
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