# Study of Properties of Composite Cementitious Materials with Sulfoaluminate Cement and Solid Waste Based on Compaction Forming Process

## TL;DR

This study explores using solid waste and sulfoaluminate cement to create strong, low-carbon materials through compaction forming.

## Contribution

The study introduces a low-carbon composite cementitious material using solid waste and optimal compaction conditions.

## Key findings

- Higher compaction pressure increases early-stage strength, with 40 MPa yielding 70 MPa compressive strength in one day.
- Adding 25% mineral powder and 20% steel slag micro powder increases compressive strength to 113.5 MPa.

## Abstract

The traditional cement compaction process boasts notable advantages such as high strength, durability, and aesthetic appeal. However, compaction forming technology for cement products results in high carbon emissions. Consequently, it is imperative to develop low-carbon strategies for these products. This study investigates the modification of solid waste-based low-carbon sulfoaluminate cementitious material (SSCM) using mineral powder (MP) and steel slag micro powder (SSMP) under compaction forming technology. The results indicate that higher compaction pressure leads to higher early-stage strength, while the later-stage strength is primarily influenced by the degree of hydration. At a compaction pressure of 40 MPa, the one-day compressive strength of the material exceeded 70 MPa, representing a 48.31% increase compared to the control group. Under compaction forming, the hydration reaction rate decreased, but the compaction process significantly reduced porosity. Moreover, higher pressure correlated with a reduction in the proportion of harmful pores. Incorporating 25% MP and 20% SSMP increased the compressive strength by 10.66% to 113.5 MPa. According to orthogonal experimental results, the optimal molding conditions entail a 20% MP content, a 20% SSMP content, and a molding pressure of 40 MPa. The research findings can serve as a theoretical foundation for the widespread application of SSCM and compaction forming technology in practical engineering.