Effect of temperature on the chloride binding capacity of cementitious materials

This study deals with the chloride binding capacity of cementitious materials. The binding capacities of ordinary Portland cement (OPC), 30% pulverized fuel ash (PFA), 60% ground granulated blast furnace slag (GGBS), and 10% silica fume (SF) pastes were monitored for 150 d using the water extraction method and the pH of the suspension (ground sample in distilled water) was simultaneously measured at 150 d. Results show that the binding capacity always increased with time, irrespective of binder, and the order of binding capacity with binders was 60% GGBS > 30% PFA > OPC > 10% SF. The pH of suspensions increased with time up to about 10 d, presumably due to a leaching out of alkalis, and then kept a certain value that was dependent on binder type. It was also found that an increase in the concentration of hydroxyl ions, derived from the pH of the suspension, resulted in a decrease in the mole ratio of free chloride to hydroxyl ions, reflecting the lower risk of steel corrosion.

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Influence of LDHs on Chloride Ion Binding in Cementitious Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.599.34 ◽

2014 ◽

Vol 599 ◽

pp. 34-38 ◽

Cited By ~ 2

Author(s):

Ping Duan ◽

Zhong He Shui ◽

Guo Wei Chen

Keyword(s):

Cement Paste ◽

Binding Capacity ◽

Mixing Time ◽

Reference Sample ◽

Chloride Ion ◽

Cementitious Materials ◽

Initial Time ◽

Ion Binding ◽

Chloride Binding ◽

Double Hydroxides

Layered double hydroxides (LDHs) materials could be used in cement and concrete for their ions capturing capacity and to enhance durability of concrete. In this work, properties and chloride binding capacity of different types of LDHs were compared, micro-mechanism of chloride binding of LDHs were analyzed and chloride binding of cement paste incorporating LDHs were investigated. The experimental results show that Mg-Al-NO3 LDHs presents higher chloride ion binding capacity at initial time compared to LDOs calcinated at 500 °C while ion binding capacity of LDHs calms down and LDOs increases with increasing mixing time. Cement paste incorporating LDHs presents higher chloride binding capacity compared with reference sample. All types of LDHs performed beneficial effect on the chloride penetration resistance especially with addition of 1% Mg-Al-NO3 LDOs.

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Chloride binding capacity of metakaolin and nanosilica supplementary pozzolanic cementitious materials in aqueous phase

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.123903 ◽

2021 ◽

Vol 298 ◽

pp. 123903

Author(s):

R. Garcia ◽

M.A. de la Rubia ◽

E. Enriquez ◽

A. del Campo ◽

J. Fernandez ◽

...

Keyword(s):

Aqueous Phase ◽

Binding Capacity ◽

Cementitious Materials ◽

Chloride Binding

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A study on chloride penetration under a dry-wet condition considering the chloride binding capacity of cement

Third International RILEM Workshop on Testing and Modelling Chloride Ingress into Concrete ◽

10.1617/2912143578.029 ◽

2005 ◽

Author(s):

K. Yamada

Keyword(s):

Binding Capacity ◽

Chloride Penetration ◽

Chloride Binding ◽

Wet Condition

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Chloride Binding Capacity and Its Effect on the Microstructure of Mortar Made with Marine Sand

Sustainability ◽

10.3390/su13084169 ◽

2021 ◽

Vol 13 (8) ◽

pp. 4169

Author(s):

Congtao Sun ◽

Ming Sun ◽

Tao Tao ◽

Feng Qu ◽

Gongxun Wang ◽

...

Keyword(s):

Binding Capacity ◽

Chloride Content ◽

Chloride Ions ◽

Fine Aggregate ◽

Chloride Binding ◽

River Sand ◽

Total Chloride ◽

Curing Period ◽

Marine Sand ◽

Bound Chloride

Chloride binding capacity and its effect on the microstructure of mortar made with marine sand (MS), washed MS (WMS) and river sand (RS) were investigated in this study. The chloride contents, hydration products, micromorphology and pore structures of mortars were analyzed. The results showed that there was a diffusion trend for chloride ions from the surface of fine aggregate to cement hydrated products. During the whole curing period, the free chloride content in the mortars made by MS and WMS increased firstly, then decreased and stabilized finally with time. However, the total chloride content of three types of mortar hardly changed. The bound chloride content in the mortars made by MS and WMS slightly increased with time, and the bound chloride content included the MS, the WMS and the RS arranged from high to low. C3A·CaCl2·10H2O (Friedel’s salt) was formed at the early age and existed throughout the curing period. Moreover, the volume of fine capillary pore with a size of 10–100 nm increased in the MS and WMS mortar.

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