Sand fixation property and erosion control through new cellulose-based curing agent on sandy slopes under rainfall

Erosion control materials with long-term effective, economical and environmentally friendly properties play a critical role in controlling erodible and unstable sandy slopes deformed under rainfall. In this study, a novel cellulose-based curing agent was developed and applied as a sustainable sand fixation materisal. The novel cellulose-based curing agent was a dual-polymer composite material (DPCM), which was prepared by mixing two kinds of organic polymer materials: carboxymethyl cellulose (CMC) and polyacrylamide (PAM). The microstructure and composition of DPCM were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The adsorption kinetics of the curing agent on sand particles was discussed by fitting with pseudo-first-order and pseudo-second-order kinetic models. Water resistance and the compressive strength of the sand-fixing specimen at different curing ages were studied. Finally, the DPCM stabilization layer’s resistance to water erosion was investigated using a rainfall simulation test. The results demonstrated that the adsorption kinetic behavior of DPCM adsorbed on sand particles followed pseudo-second-order kinetics. Additionally, the interaction between the DPCM and sand particles was primarily hydrogen bonding, covalent bonds, and physical adsorption. The compressive stress was in the range from 53 to 915 kPa. Sandy slopes treated by DPCM showed excellent resistance to water erosion under a rainfall intensity of 120 mm/h.