Research On The Carbonation Of Concrete With High Volume Mineral Admixtures

The carbonation of concrete problem as one of the important issues of its durability, for the sustainable development of the reinforced concrete structure building today plays a decisive role. Along with the social development, the concrete with high content mineral admixtures is respected by people gradually, and because of its own mineral admixture is more, are more likely to cause the problem of concrete carbonation, therefore, for a large concrete with high content mineral admixtures is the study of the problems of the carbide has the very vital significance.Based on the mechanism of concrete carbonation is introduced, collecting and sorting the prediction model of concrete carbonation are related, water-binder ratio, mineral admixture content, proportion relationship and carbonation resistance agent on the curing time is big with high content mineral admixtures is the influence of concrete carbonation resistance performance is studied through experiments. Study found that early water-binder ratio on concrete carbonation resistance(7 days and 14 days), can be ignored, but had significant effects on the later(28 days), within the scope from 0.45 to 0.65 of the water/cement ratio increased by 0.1, the carbonation depth of the concrete would increase 35.4%; Increase the dosage of fly ash is not conducive to maintain itself carbonation resistance of concrete; At the same time, in certain cases, the total mineral admixtures with ground granulated slag, the carbonation resistance of concrete performance gradually improved, including 7 and 28 days of concrete carbonization conditions improved significantly; In the amount of mineral admixtures and water-binder ratio under the premise of keeping the mixed concrete carbonation resistance of agent for the carbonation resistance of concrete have played an important role to improve; The carbonation depth of concrete will as the carbonization time extended and deepened, when the maintenance time is not more than 14 days, concrete carbonation rate faster, but the rate of carbonization of concrete curing after 14 days will slow; For large concrete with high content mineral admixtures is the relationship between the compressive strength and carbonation depth is given priority to with linear correlation, and the relationship with the extension of concrete carbonization time and even more significant.In this paper, the experimental material selection in qinhuangdao commercial concrete commonly used raw materials, the experimental results of qinhuangdao district commercial concrete carbonation resistance design has a guiding role, has a certain reference significance for other regions.