Influence of seawater on reinforced mortars with varying fly ash replacement ratio, water binder ratio, curing conditions and type of steel bars

• Main Author: Lim, Edrick Dan P.
• Format: text
• Language: English
• Published: Animo Repository 2012
• Subjects: Mortar—Testing; Seawater; Binders (Materials); Steel bars; Fly ash; Substitution reactions; Substitution (Technology); Civil and Environmental Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/6840
• Institution: De La Salle University

By 2025, more than 3 billion people could be living in water-stressed areas and fresh water scarcity will soon become one of the major problems that would strike developing countries. In the construction industry, mixing water alone accounts for more than 1 trillion liters of fresh water usage per year. To be able to use readily available materials without the need of production or treatment, such as the seawater, would greatly contribute into preventing fresh water scarcity around the world. This study reports the results of using seawater as mixing and curing water on the properties of reinforced mortars. The compressive strength, corrosion rate and chloride content were the key means of measurement in the determining the effects of seawater. Data was obtained from four varying parameters and these are: the fly ash replacement ratio, water-binder ratio, curing conditions and types of steel bars. Results show that the use of seawater as mixing water gave roughly the same amount of compressive strength as when fresh water is used and behaved nearly the same way even when fly ash replacement and water-binder ratio were varied. However, when cured and exposed to seawater, either type of mixing water gave a relatively lower value for compressive strength. In terms of corrosion, seawater mixed specimens did not produce a higher corrosion rate so as long as it is cured with fresh water. Generally, the main factor that contributed to a high corrosion risk is the curing and exposure to seawater. Slight corrosion in the initial condition of the steel bars did not yield a faster corrosion rate than that of regular non-corroded bars.