Experimental Study and Hydration Mechanism Analysis of Geopolymer Multielement Net Slurry Self-Leveling Slurry...

Area of Science:

• Materials Science
• Civil Engineering
• Geochemistry

Background:

• Cement-based composites are crucial in construction.
• Utilizing industrial byproducts like slag powder (SP), steel slag powder (SSP), and desulfurization gypsum (FGD) offers sustainable alternatives.
• Understanding their mechanical properties and strengthening mechanisms is vital for effective application.

Purpose of the Study:

• To systematically investigate the preparation, mechanical properties, and strengthening mechanisms of cement-based composites reinforced with SP, SSP, and FGD.
• To analyze the particle size distribution of the raw materials.
• To evaluate the impact of different alkali activators on compressive strength and hydration products.

Main Methods:

• Particle size analysis using a laser particle analyzer (Malvern Instruments Analysis).
• Preparation of cement-based composites with varying ratios of SP, SSP, and FGD (e.g., 6:3:1, 7:2:1).
• Mechanical property testing and microscopic scanning (e.g., SEM) to analyze hydration products (AFt, C-S-H gels) and pore structure.

Main Results:

• Raw SSP, SP, and FGD materials are fine-grained minerals (5–40 μm).
• SSP and SP exhibit high alkalinity, contributing to composite reactivity.
• Calcium hydroxide (Ca(OH)2) demonstrated the strongest compressive strength activation effect among tested alkali activators (Ca(OH)2 > Na2SiO4 > NaOH).
• Hydration resulted in the formation of AFt and C-S-H gels, but water curing led to surface efflorescence and internal porosity.

Conclusions:

• Cement-based composites incorporating SP, SSP, and FGD can be effectively prepared.
• The choice of alkali activator significantly impacts the mechanical performance, with Ca(OH)2 being most effective.
• While hydration produces beneficial gels, efflorescence and porosity require further mitigation strategies for optimal material performance.