Experimental study on ecological fiber improvement of drying shrinkage cracks in sandy clay

Sandy clay has poor water retention capacity and is prone to significant drying shrinkage cracks under evaporation, which exacerbate rainfall infiltration on slopes, increasing the risk of instability. This study investigates the inhibitory effects of different eco-fibers on drying shrinkage cracks in sandy clay. Using image processing techniques, the effects of jute fiber and rice straw fiber on water evaporation, crack development, evolution, and structural morphology of sandy clay were quantitatively analyzed. Results show that eco-fibers exhibit strong adhesion with soil particles and can effectively suppress drying shrinkage cracks in sandy clay by delaying water evaporation and reinforcing the soil. The inhibitory effects improve with increasing fiber content. At a fiber content of 0.6% (by mass), jute fiber and rice straw fiber demonstrated the most significant improvement, reducing crack ratios by 30.6% and 23.8%, respectively, and average crack widths by 66.64% and 70.86%, respectively. The use of jute and rice straw fibers provides novel approaches and theoretical support for addressing drying shrinkage cracks in sandy clay fill engineering.