Abstract
In recent years, microbial induced calcium carbonate precipitation (MICP) and vegetation slope protection technology have been proven to be feasible. However, since the process of MICP-improved vegetation slope protection is affected by factors such as vegetation type, the research on the adaptability and stability of roots in the root-soil complex is still not in-depth. Therefore, this paper carried out plant adaptability and erosion resistance tests and triaxial tests on MICP-solidified root-soil complexes to explore the changing laws of vegetation germination adaptability, erosion resistance and soil mechanical properties under the action of MICP solidification. The results showed that: (1) Tall fescue germination potential declined from 72.3 to 40.7% with increasing reaction solution concentration, and more sharply from 66 to 26.5% as the number of spray applications increased. Paspalum notatum showed a similar trend, decreasing from 11.4 to 2.2% (concentration) and from 8.5 to 1.2% (spray applications). Overall, the number of spray applications exerted a greater inhibitory effect than concentration. (2) Microorganisms can enhance the ability to resist erosion. After 6 sprayings, the erosion rate is only 1.5%. Microorganisms combined with plants can significantly inhibit continuous rainfall; (3) The stress-strain curve of MICP-reinforced root-soil composite shows an upward trend and is a strain hardening type. Roots can promote the formation of calcium carbonate, cement the soil and fill the pores, so that the c and φ values of the MICP-reinforced root-soil complex are positively correlated with the calcium carbonate and root content, and the C value increases more significantly; (4) MICP technology has a great influence on the root The strength increase ratio of soil composite strength is very important, and its MICP strength increase ratio is as high as 80% under the optimal root content. MICP can effectively improve the adaptability of vegetation slope protection technology and improve the stability of slopes. Therefore, it can be considered that MICP has important significance for improving the stability of slopes by improving vegetation slope protection technology.