Freeze-thaw durability factor

Freeze-thaw durability factor Fly ash and aggregates 89.7% after 300 cycles Road-based and permafrost applications... 

The superior resistance to a vari ety of degrad i ng effects was reported by Bonneau etal. [59] for RPC freeze-thaw-durability factor equal or greater than 1 scaling-cumulative mass of scaling residue less than 0.03 kg/m (compared with a maximum of 0.80 kg/m allowed in the standards) chloride permeability (ASTM Cl 202) - less than 10 Coulomb (from a practical point of view this is impermeable concrete a range of 500-1000 Coulomb is considered as high performance concrete). The permeability under load conditions, in which cracks are induced, was evaluated by Charron et ai [60] showing that at strains of up to 0.13% the permeability was as low as that of the matrix. This is an indication of the durability potential of such composites under load. 

Table 3.23 The effect of spacing factor on freeze-thaw durability...

The use of superplasticizers in air-entrained concrete has caused much debate. Two main problems are associated with superplasticized air-entrained concrete (1) a decrease in air content by 1-3% when slump is increased from 75 mm to 220 mm after the addition of the superpiasticizer to create flowing concrete, and (2) a change in the air void system to less desirable values. However, most investigators [10-11, 12] have shown that, although the air-void spacing factor required for adequate frost resistance is altered, the change did not necessarily affect the freeze-thaw durability of... 

Ai tcin, P. C. (1998) The influence of the spacing factor on the freeze-thaw durability of high performance concrete, in Int. Symp. on High-Performance and Reactive Powder Concretes, August, Canada Universite de Sherbrook pp. 419-33. 

Water-reducing admixture Dosage Air-entraining agent type Water-cement ratio Freeze-thaw data Durability factor (%) Weight loss (%)... 

Air-entraining admixture % air by volume Average spacing factor (mm) Durability to freeze-thaw cycling ... 

In this study, micro-structured polypropylene and glass fibers were both used sep>arately and in combination with macro-structured steel fibers in the concrete. Experiments were conducted in order to determine weight-loss and durability factor based on ultrasoimd pulse velocity of 12 different concrete series produced according to ASTM C-666. The separate and combined effects of the fibers used in the concrete in terms of the rapad freeze-thaw period were investigated. 

Fig. 3. Durability factors determined after freeze-thaw cycles.

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