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Freeze-Thaw Resistance of FRC Materials
Published in R. N. Swamy, Fibre Reinforced Cement and Concrete, 1992
In the large program of Balaguru and Ramakrishnan (1986, 1988) the following could be concluded on the freeze-thaw resistance of steel fibre reinforced concrete: The air content is the most significant parameter for the freeze-thaw resistance.If air content is the same, the durability of fibre reinforced concrete and plain concrete is similar.With the same air entrainment, the frost resistance may be improved by increasing the cement content and reducing the water-cement ratio.With a water-cement ratio of more than 0.4 and a cement content less than 415 kg/m3, a minimum of 6.0 percent air, preferably 8.0 percent, should be used to avoid deterioration under freeze-thaw cycling according to ASTM C666. Proctor (1980) reported results from freeze-thaw tests on glass fibre reinforced composites. The conclusions were that freeze-thaw conditions do not pose a significant problem in the use of GRC.
Freeze–thaw and thermal cycle durability of pervious concrete with different aggregate sizes and water–cement ratios
Published in International Journal of Pavement Engineering, 2021
Yan Tan, Chenxu Zhou, Chuheng Zhong, Jinzhi Zhou
In the freeze–thaw test, standard 100 × 100 ×100 mm specimens were used, as Figure 3 shows. In accordance with Chinese standard GB/T 50082–2009 (China 2009a), temperatures of freeze–thaw cycles ranged from –17 ± 2°C to 8 ± 2°C. Mass loss and compressive strength were recorded every seven freeze–thaw cycles. According to the standard, 25 freeze–thaw cycles are selected, the amount of data is too small to reflect the test results. Seven freeze–thaw cycles have more data to reflect the test results. The number of freeze–thaw cycles when the mixture was damaged and the freeze–thaw life were used as the index for evaluating freeze–thaw resistance.
Assessing durability properties of noise barriers made of concrete incorporating bottom ash as aggregates
Published in European Journal of Environmental and Civil Engineering, 2019
Carlos Leiva, Celia Arenas, Luis F. Vilches, Fatima Arroyo, Yolanda Luna-Galiano
Porous concrete with macro-pore structure is easily deteriorated when subjected to freeze-thaw cycles. Freeze-thaw resistance is usually measured in terms of mass loss after a number of successive freeze and thaw cycles. In this work, all the porous materials experimented a mass loss of 15% after 30–40 cycles, similar to the other porous concretes fabricating using wastes as aggregates (Chandrappa & Biligiri, 2017). In order to increase the freeze–thaw resistance, other researchers have reported different additives such as air-entraining agents, silica fume with super plasticisers, tire chips and crumb rubber (Wu et al., 2016).
Effect of fibre type and utilisation rate on dimensional stability and frost resistance of pavement mortar mixture
Published in International Journal of Pavement Engineering, 2023
Yahya Kaya, Öznur Biricik, Sultan Husein Bayqra, Ali Mardani
As seen in Table 8, the compressive strength of the mixtures decreased by the increase in fibre utilisation ratio in all fibre mixtures except PP-0.50% mixture. As previously emphasised, the water absorption rate increases as the void volume increases in the mixture with the use of fibre. Thus, more water is predicted to penetrate into the mixture as a result of the increased permeability in fibrous mixtures. This case negatively affects the freeze–thaw resistance of the mixture (Chen et al., 2020). On the other hand, adding materials that can entrain air to the mixture is a well-known practice to increase the freeze–thaw resistance in cementitious systems (Mo et al., 2017, Yap et al., 2020). Fibre addition creates air gaps in the mixture which gives rise to an area where water can escape. In addition, fibre addition increases the tensile strength of the mixtures which results in the prevention of the potential micro-cracks. These conditions increase the freeze–thaw resistance of the sample (Zhang and Li, 2014). Therefore, the fibre utilisation rate and whether the fibre is homogeneously dispersed in the mixture determine the freeze resistance of the mixture. The fibre-free control mixture exhibited the lowest freeze–thaw performance with an approximate 70% strength loss (Table 7). Regardless of the fibre type, the strength loss due to freeze–thaw in the mixtures was found to decrease as the fibre utilisation rate increased. This case is attributed to the formation of extra spaces where water can escape during freezing depending on the increase in fibre dosage. In their study, Richardson et al. (2012) have similar results as well. Figure 10 shows the relationship between the compressive strength of the samples exposed to 300 cycles of freeze–thaw and the values of UPV. The studies conducted in the literature reveal that the R value is close to 1 in the compressive strength-UPV ratio relations of fibre-free concrete mixtures (Zebari et al., 2016).