Restructuring the Basic Design of Several Accelerator-Based Concrete Mixes by Integrating Superplasticizers.

Area of Science:

• Materials Science
• Civil Engineering
• Construction Materials

Background:

• Growing infrastructure demands and climate change necessitate improved concrete performance.
• Traditional concrete faces limitations in durability and functionality.
• Novel additives are explored to enhance concrete properties.

Purpose of the Study:

• To investigate the effects of three accelerators (calcium nitrate, aluminum sulfate, sodium thiosulfate) and superplasticizers on standard concrete.
• To evaluate the impact of these additives on concrete's physical and mechanical properties.
• To identify concrete mixtures suitable for replacing traditional concrete with enhanced functionality.

Main Methods:

• X-ray diffraction (XRD) for structural analysis.
• Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) for microstructural examination.
• Water absorption, bulk density, and compressive strength tests were conducted.

Main Results:

• All concrete mixes exhibited similar crystalline structures (quartz, portlandite, larnite, etc.).
• Microstructural analysis revealed ettringite, portlandite, and C-S-H gel.
• Superplasticizer addition reduced pore radius, increased compaction, lowered bulk density, and enhanced compressive strength.

Conclusions:

• All tested concrete mixtures are comparable to standard concrete and can be used as replacements.
• The concrete mixture containing sodium thiosulfate and a superplasticizer demonstrated superior compressive strength.
• These enhanced concrete formulations offer improved functionality for infrastructure applications.