Concrete frost damage - Concrete allows frost to be critical strength

Concrete frost damage and concrete allow the critical strength of frozen 1, concrete frost damage: According to the concrete age and frost conditions, can be divided into concrete frost damage and concrete early frost damage two categories. â‘  Frozen concrete, refers to the hardened concrete, after the use of investment, after years of freezing and thawing, the concrete to some of the performance suffered damage reduced or destroyed. The test uses multiple freeze-thaw cycles as a measure of strength or modulus of elasticity. Used to assess the useful life of the project structure. â‘¡ Early frost damage of concrete means that the concrete after pouring is in the stage of condensation, hardening or curing. Before being put into use, the concrete is frozen or frozen and thawed to be frozen due to the negative temperature attack, so as to reduce a series of performance, To design and usage requirements. The test uses one or more freezing methods. As a critical strength assessment index. 2, the critical strength of frozen concrete: newly poured concrete reached a certain initial value before freezing, was frozen, when the restoration of positive temperature curing concrete strength can continue to grow, and then after 28 d after the standardization of the intensity Loss does not exceed 5%. At this time, the initial intensity before freezing is called the critical strength of frozen soil. Portland cement or ordinary portland cement prepared concrete allows the critical strength of the frozen to 30% of the design strength grade; slag Portland cement prepared concrete allows the critical strength of the frozen to 40% of the design strength grade â‘  winter pouring The concrete water-cement ratio shall not exceed 0.6. Because the critical strength value is tested on the premise of the water-cement ratio is not greater than 0.6, so when the concrete construction in winter, when the water-cement ratio is greater than o.6, the strength loss will exceed 5%, less than the design Claim. â‘¡ The design strength grade here refers to the design strength grade of the construction mix ratio, not the design strength grade marked on the design drawing. (This article has Asian Fluid Network members Yao country fluid equipment editor release, please indicate Asia Fluid Network, to promote business consulting hot like :, or add QQ :)