コンクリートの凍害の環境要因効果に関する実験的研究 : コンクリートの耐凍害性におよぼす環境要因の影響(その1)

抄録

The influence of environmental conditions on the frost damage of concrete was studied, by using concretes of three frost durable and of three suceptible in accordance with test programs of experimental testing methods. After curing for three weeks under various conditions such as in air and in water, almost all concrete samples were frozen and thawed in water under the freezing process. Test results were summarized as follows. 1) No concrete was damaged when the test was carried out with a minimum temperatuer of -2℃, but the extent of damage had a tendency to become severe in proportion to a drop in the minimum temperature of the freezing process. 2) The condition, of the concrete before the process of freezing and thawing also had an-important effect on the frost damage of concrete. Curing in air for one week being after immersed in water increased the frost resistance remarkably in all concrete samples. 3) The test condition of freezing in air had a fairly small effect on the frost damage of concrete compared with that of freezing in water. 4) Conditions of freezing rates and of periods of maintained minimum temperatures also had an effect on the frost damage of concrete.