Characteristics of the 80MPa High Strength Concrete according to the Hot Weather Outside Temperature conditions

Title & Authors
Characteristics of the 80MPa High Strength Concrete according to the Hot Weather Outside Temperature conditions
Jung, Yong-Wook; Lee, Seung-Han;

Abstract
This paper evaluates the effect of hot weather conditions on the fresh concrete characteristics of 80-MPa high-strength concrete. The slump flow, packing ability, setting time, hydration heat, and compressive strength were evaluated under exterior temperatures of $\small{20^{\circ}C}$, $\small{30^{\circ}C}$, and $\small{40^{\circ}C}$. The slump flow, arrival speed of 500 mm, and their changes with the elapsed time were found to bring the occurrence of rapid slump loss forward by about 30 minutes when increasing the temperature by $\small{10^{\circ}C}$ from $\small{20^{\circ}C}$. The initial and final setting times of the concrete at $\small{20^{\circ}C}$ were 7 hours and 12 hours, which were reduced by 1 hour and 3 hours at $\small{30^{\circ}C}$ and by 2 hours and 5 hours at $\small{40^{\circ}C}$, respectively. The hydration heat characteristics at $\small{20^{\circ}C}$ and $\small{30^{\circ}C}$ were similar in terms of the highest temperature of the concrete casting depth and the time when the maximum temperature occurred. However, at $\small{40^{\circ}C}$, the maximum temperature occurred about 4 hours earlier, and the highest temperature per the concrete casting depth increased by about $\small{12^{\circ}C}$. Therefore, it is concluded that the characteristics can vary according to the exterior temperature. Thus, quality assurance should consider workability, temperature cracks due to hydration heat, the properties of strength development, and other characteristics.
Keywords
Hot weather;Exterior temperature;High strength;Elapsed time change;
Language
Korean
Cited by
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