Light microscopic imaging of sand, sand-chitosan and sand-xanthan gum mixtures and rheology of xanthan gum and chitosan solution, in Supplementary Information - Mechanical and Strength Degradation Characteristics of Sandy Soil Reinforced with Xanthan Gum and Chitosan Biopolymers

This project contains supplementary information for the peer review of the manuscript titled “Mechanical and Strength Degradation Characteristics of Sandy Soil Reinforced with Xanthan Gum and Chitosan Biopolymers.” The repository includes four supplementary files. Three video files (SI- I to III) document the time-dependent drying behavior of untreated sand and sand treated with xanthan gum and chitosan, recorded using optical microscopy to illustrate microstructural evolution and particle–polymer interactions during drying. These supplementary information are designed to clarify the time dependent change of soil-polymer mixtures which can not be fully represented via still images in the main body of the manuscript. The other supplementary document (SI-IV) presents rheology of the polymer solutions used in the experiments. SI-IV also explains the experimental procedure for measuring polymer rheology and support interpretation of the reported results. The project is intended for reviewers for additional methodological and microstructural insight beyond the main article.