Frost-salt Testing Non-air Entrained High-performance Fly-ash Concrete Part II: Parameter Study of Effect of Internal Cracking on Glue Spall Stress

A parametric analysis of glue spall stress (concrete surface tensile stress at ice-discontinuities by differential thermal expansion ice-concrete) as affected by internal cracking in concrete in the CEN/TS 12390-9 salt-frost slab-test was made. Increasing differential thermal expansion ice-concrete (∆α) and reduced E-modulus and Poisson ratio (ν) due to internal cracking were used based on data from Part 1 of this study. For the concrete specimens in Part 1 of this study [1] glue spall stress increased by 14 % due to internal cracking whereas reduced ice thickness of 1 – 2 mm due to accelerated Liquid Uptake (LU) in wet freeze/thaw reduced glue spall stress by 34 to 65 %. LU should hence be accounted for in modelling scaling, both due to reduced ice thickness and increased ∆α due to internal cracking. Increased crack penetration depth and its effect on scaled particle size due to internal cracking were also analyzed.