Influencing Factors of Porosity and Strength of Plant-Growing Concrete

• Published in: Materials Vol. 17; no. 1; p. 31
• Main Authors: Cai, Jiashi, Shen, Chunying, Ye, Ming, Huang, Siyang, He, Jinxing, Cui, Ding
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20.12.2023; MDPI
• Subjects: Aggregates; Analysis; Cement; Compressive strength; Concrete mixing; Engineering; Experiments; Failure mechanisms; fitting; Fly ash; Grasses; Mechanical properties; Optimization; Particle size; Permeability; Plant growth; plant-growing concrete; Plants (botany); Porosity; Porous materials; preparation process; Pressure molding; Ratios; Retention; Soil porosity; Specimen preparation; Stress concentration; stress–strain curve; Substrates; Vegetation; China; compressive strength; stress–strain curve; preparation process; porosity; plant-growing concrete; planting test; fitting
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17010031

A standardized preparation process is proposed in this study for achieving optimal strength and vegetative properties in vegetated concrete, using Yunnan red soil as a growth substrate for plants. The porosity of vegetated concrete is a crucial factor influencing plant growth, while compressive strength is a significant mechanical property. To assess the strength and porosity of vegetated concrete, different design porosities (22%, 24%, 26%, 28%) and cement-to-aggregate ratios (4, 5, 6, 7) were utilized in the preparation of vegetated concrete samples. The shell-making and static-pressure-molding methods were optimized for specimen preparation. Analyzing the stress-strain full curve characteristics of vegetation-type concrete under different influencing factors, an in-depth investigation into its failure mechanism was conducted. It was determined that the design porosity and cement content significantly impact the concrete's performance, particularly in terms of 30-day compressive strength and effective porosity. Furthermore, an increase in the fly ash ratio led to an increase in porosity and a decrease in compressive strength, providing a certain guidance for optimizing concrete performance. Comparative analysis through vegetation experiments revealed that black rye grass exhibited favorable growth adaptability compared to other grass species.