Furthermore, the effect of ternary cementitious systems with regard to chloride penetration tended to be more noticeable as the type of cementitious materials and their replacement percent changed as clarified in Table 4 and Fig. 1, Fig. 2 and Fig. 3. Also, The second and third zones (i.e., 10–20 mm and 20–30 mm) of tested concrete of ternary cementitious system indicate lower values of chloride contents than those of the OPC concrete. The rates of increase in chloride contents with time in the case of OPC concrete are larger than those of concrete of ternary cementitious system.
Marusin (1989) mentioned that the corrosion threshold limit for soluble chloride ion concentration in normal weight reinforced concrete is about 0.03% by weight of concrete. The soluble chloride contents for all the tested samples after 5 months at the depth 20–30 mm concrete are lower than the above mentioned limits for corrosion threshold. Ternary cementitious mixtures have lower soluble chloride content, which leads to conclude that using concrete containing ternary cementitious systems may reduce the depth of cover needed to protect the reinforcing steel. Gaynor (1987) reported that 0.5–0.75 of penetrated chlorides ions in hardened concrete are soluble in water and free to contribute to corrosion.
The obtained results for all studied mixtures show lower percent of soluble/total chloride than that reported by Gaynor (1987). The mixes containing ternary cementitious systems show lower ratios of soluble/total than those of OPC mix. Anwar and Sakai (2007) reported that concrete of binary cementitious systems (silica fume, blast-furnace, fly ash) indicated lower chloride content than OPC mix as well as lower ratio of soluble/total chloride content, which complies with the obtained results.
Fig. 1, Fig. 2 and Fig. 3 indicate that, the binary system (mixes 2–5) results of the total and soluble chloride ion contents were better than the control mix (mix 1) about 20%. Moreover, the ternary system (mixes 6–9) results of the total and soluble chloride ion contents were better than the control mix about 40–60%. Mix 9 (10% SF and 25% FA) gave the best results in terms of total and soluble chloride ion contents at all tested depths.
Table 5 lists the results of the total and soluble chloride ion contents for the studied mixes as percentage by weight of concrete after 5 months at depths from 30 mm to 50 mm. The results indicate that the levels of total and soluble chloride contents were very small for all mixes, nevertheless the results of binary and ternary systems were better than the control mix by 10–50% for different depths after 5 months.
Furthermore, the effect of ternary cementitious systems with regard to chloride penetration tended to be more noticeable as the type of cementitious materials and their replacement percent changed as clarified in Table 4 and Fig. 1, Fig. 2 and Fig. 3. Also, The second and third zones (i.e., 10–20 mm and 20–30 mm) of tested concrete of ternary cementitious system indicate lower values of chloride contents than those of the OPC concrete. The rates of increase in chloride contents with time in the case of OPC concrete are larger than those of concrete of ternary cementitious system.Marusin (1989) mentioned that the corrosion threshold limit for soluble chloride ion concentration in normal weight reinforced concrete is about 0.03% by weight of concrete. The soluble chloride contents for all the tested samples after 5 months at the depth 20–30 mm concrete are lower than the above mentioned limits for corrosion threshold. Ternary cementitious mixtures have lower soluble chloride content, which leads to conclude that using concrete containing ternary cementitious systems may reduce the depth of cover needed to protect the reinforcing steel. Gaynor (1987) reported that 0.5–0.75 of penetrated chlorides ions in hardened concrete are soluble in water and free to contribute to corrosion.The obtained results for all studied mixtures show lower percent of soluble/total chloride than that reported by Gaynor (1987). The mixes containing ternary cementitious systems show lower ratios of soluble/total than those of OPC mix. Anwar and Sakai (2007) reported that concrete of binary cementitious systems (silica fume, blast-furnace, fly ash) indicated lower chloride content than OPC mix as well as lower ratio of soluble/total chloride content, which complies with the obtained results.Fig. 1, Fig. 2 and Fig. 3 indicate that, the binary system (mixes 2–5) results of the total and soluble chloride ion contents were better than the control mix (mix 1) about 20%. Moreover, the ternary system (mixes 6–9) results of the total and soluble chloride ion contents were better than the control mix about 40–60%. Mix 9 (10% SF and 25% FA) gave the best results in terms of total and soluble chloride ion contents at all tested depths.Table 5 lists the results of the total and soluble chloride ion contents for the studied mixes as percentage by weight of concrete after 5 months at depths from 30 mm to 50 mm. The results indicate that the levels of total and soluble chloride contents were very small for all mixes, nevertheless the results of binary and ternary systems were better than the control mix by 10–50% for different depths after 5 months.
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