Orthogonal Experimental Study on Concrete Properties of Machine-Made Tuff Sand.

Area of Science:

• Materials Science
• Civil Engineering
• Sustainable Construction

Background:

• Natural sand scarcity necessitates alternatives for the concrete industry.
• Machine-made sand offers a sustainable solution for concrete production.
• Investigating the performance of machine-made sand is vital for its adoption.

Purpose of the Study:

• To determine the optimal mix ratio for machine-made tuff sand concrete.
• To analyze the factors influencing the mechanical and working properties of this concrete.
• To compare the performance of machine-made tuff sand concrete with other fine aggregates.

Main Methods:

• Orthogonal experimental design was employed to optimize concrete mix ratios.
• Grey correlation analysis was used to identify key factors affecting concrete properties.
• Working performance and mechanical properties were experimentally verified.

Main Results:

• The sand rate significantly impacts slump and slump expansion.
• Mineral admixture is critical for 7-day compressive strength; water-cement ratio for 28-day strength.
• Optimal mix: 20% mineral admixture, 46% sand rate, 10% stone powder, 0.30 water-cement ratio.
• Machine-made tuff sand concrete exhibits comparable properties to limestone and river sand concrete.

Conclusions:

• Machine-made tuff sand concrete offers a viable and sustainable alternative to natural sand.
• Specific mix proportions are identified for optimal mechanical and working performance.
• Understanding factor influence aids in quality control for machine-made sand concrete.
• Stone powder content has minimal impact on compressive strength within a certain range.