Effect of LDH on the dissolution and adsorption behaviors of sulfate in Portland cement early hydration process

In recent years, it has been widely recognized that the incorporation of Mg-Al-LDH into cement-based materials can improve the salt corrosion resistance of cement-based materials. The reason for the improvement comes from the anion adsorption capacity of Mg-Al-LDH. It was confirmed that the addition of Mg-Al-LDH would accelerate the setting and hardening of cement paste. With the increase in the Mg-Al-LDH content, the initial setting time of cement slurry with different gypsum contents will decrease by 10-50% and the viscosity of the cement slurry will increase by 100-200%. Depending on different gypsum contents, the degree of cement hydration varied. This article also found that the gypsum in the cement has a negative effect on the resistance to salt erosion, which was brought about by the Mg-Al-LDH adsorption capacity.

Automated summary

It has been recognized that incorporating Mg-Al-LDH into cement-based materials can improve their resistance to salt corrosion. The adsorption capacity of Mg-Al-LDH accelerates the setting and hardening of cement and the presence of gypsum in the cement affects its hydration degree.