【Daily Topic】【Civil Engineering Version 20160114】
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This post was last edited by hesonchang214 on 2016-1-14 09:54. Reward for participation: 2 Wealth. Reward for correct answer: 9 wealth. Multiple-choice question: Regarding the carbonation of concrete surfaces, which of the following statements are correct? ( ) A. Reduces the alkalinity of concrete B. Weakens the protective effect of concrete on steel rebar C. Increases the compressive strength of the concrete surface D. Increases the tensile strength of the concrete surface E. Reduces the flexural strength of concrete
ABCE~~~~~~~~~~~~~~~~~~~~~~~~
Regarding the statements about carbonation of concrete surfaces, the correct ones are (A, B, C, E).
Regarding the statements about carbonation of concrete surfaces, the correct ones are (A B C E). A. Reduces the alkalinity of concrete B. Weakens the protective effect of concrete on steel rebar C. Increases the compressive strength of the concrete surface D. Increases the tensile strength of the concrete surface E. Reduces the flexural strength of concrete
A, B, C, E. ----------------------------
Regarding the statements about carbonation of concrete surfaces, the correct ones are (A B C E). A. Reduces the alkalinity of concrete B. Weakens the protective effect of concrete on steel rebar C. Increases the compressive strength of the concrete surface D. Increases the tensile strength of the concrete surface E. Reduces the flexural strength of concrete
Regarding the statements about carbonation of concrete surfaces, the correct ones are (ABCE).
The correct ones are (ABCE).
The ABCE principle involves carbon dioxide in the air reacting with calcium hydroxide in the cement paste to produce calcium carbonate and water. Features: Alkalinity decreases, weakening the concrete’s protective effect on steel rebar; concrete shrinkage increases; compressive strength rises, while tensile and flexural strengths decrease.