Mechanical Characteristics and Planting Performance of Ecological Concrete Produced Using Low-Quality Aggregate

Low-quality rocks obtained from engineering excavation generally are considered to be unsuitable for direct application and are typically discarded. This practice results in challenges such as land utilization and environmental contamination. In this study, low-quality rocks obtained from earthwork excavation in engineering projects were utilized as aggregates in the production of ecological concrete to reduce construction waste emissions. The mechanical characteristics and planting performance of ecological concrete produced with low-quality aggregates were investigated. The results indicated that with 12% silica fume and 10 kg/m3 polypropylene fiber, the 28-day compressive strength of the ecological concrete reached 7.64 MPa, with a pH of 9.25 and a porosity of 25.3%. Furthermore, the pH of the ecological concrete decreased from 9.25 to 8.03 after treatment with a 5% FeSO4 solution. Notably, after 28 days of cultivation, the roots of tall fescue successfully penetrated the ecological concrete. The ecological concrete produced with low-quality aggregates exhibited commendable performance in terms of compressive strength and its suitability for supporting plant growth. This study provides a novel approach for the utilization of earthwork resources.