해양환경 초고층 매트기초 시공을 위한 저발열 자기충전 콘크리트 개발

Abstract

Recently, buildings are becoming larger and taller and many tall buildings are being built around the coast for great views. Therefore, high strength, high flow concrete for tall buildings is required and concrete according to each properties is required, such as high durability concrete in the marine environment and a method to control the heat of hydration generated during large-scale concrete pouring. However, in the planning and construction of tall buildings in the marine environment, there is little in the way of deriving an optimized combination and constructing and analyzing data on the actual construction performance related. In this study, the correlation of low heat and self-consolidating concrete is analyze based on the analysis and measurement of the performance requirements related to the concrete mixed design required for the construction of tall buildings in the marine environment. The results of this study are summarized as follows. (1) In order to give low heat self-consolidating performance, the water/binder ratio was set at 34.4%, the fine aggregate ratio 54%, the mixing water 155kg/㎥, and the binder amount 450kg/㎥. And a specific concrete mixing design was derived in which the ratio of the 4-component mixed cement was 18% cement, 50% blast furnace slag, 27% fly ash, and 5% silica fume. As a result the quality control standards for the slump flow of 650±50㎜, air volume of 3.5%±1.5, and design standard strength of 45MPa, that they require performance is satisfied. (2) The carbonation ​coefficient is , which is judged that the carbonation resistance performance is very good. And result of evaluation of salt resistance performance and sulfuric acid resistance performance, chloride-ion penetration characteristics were stable, and it was found to be applicable to severe sulfate environmental conditions. (3) Through the adiabatic temperature rise test, the maximum adiabatic temperature rise( K ) was 28.1℃, and the reaction rate (α) was 0.924℃/hr. It is judged to represent the performance of low heat concrete. (4) Through actual construction, the maximum hydration temperature was measured at 45.3℃, which is about 60% compared to similar sites, and curing period can be shortened up to 43 days, which is judged to have low heat properties. (5) In the future, it is judged that high quality construction will be possible if the mixing factors for each required performance established in this study are used in the marine environment MAT foundation concrete mixing design with a design strength of 45MPa.