Properties of concrete with seawater and powdered mussel shells as partial cement replacement

• Main Authors: Hong, Paul Ray F., Ibanez, Mark Denzel C., Reyes., Alyssa Anne R., Uy, Mary Olivienne G.
• Format: text
• Language: English
• Published: Animo Repository 2018
• Subjects: Building materials; Cement; Civil Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/6448
• Institution: De La Salle University

Due to the increasing demand of construction materials, several studies have been conducted regarding the utilization of alternative materials as partial replacements or substitutes for the components of concrete. Moreover, with the aim of producing sustainable concrete, the researchers produced concrete which utilized seawater as a substitute for fresh water and powdered mussel shells as partial replacement for cement. The research was limited in utilizing green mussel shells at 0%, 10%, and 20% partial replacement for cement fresh water and sea water for mixing and water cement ratios 0.4 and 0.6. In previous studies, the highest compressive strength was found at 10% cement replacement. This was found to be the most common optimum percentage replacement of powdered seashells. In addition, other researchers found other optimum percentatge replacements which are below 10%. Moreover, by using 10% and 20% replacement in this study, the increase of powdered mussel shells (PMS) resulted to a decrease in compressive strength. The decrease in strength happens when there is excessive PMS content which is more than the optimum percentage. Due to the limitation, the optimum percentage replacement may have fallen within the range of 0% to 10%. It was also concluded that the compresive strength of concrete increased with the utilization of seawater. This is due to the salt content of the seawater which acts as an accelerator and increases the strength of concrete. Lastly, comparing the 0.4 and 0.6 water-cement ratios, the compressive strengths of each 0.4 concrete mix design which had the same percentage of partial cement replacement and type of mixing water. This is because the concrete mixes with 0.4 water-cement ratios have a higher volume of cement compared to the concrete mixes with 0.6 water-cement ratio.