The cracking mechanism and morphology of earthen archaeological sites

This study investigates the cracking patterns of archaeological sites under different domestic environmental conditions. The research further explores the correlation between soil properties and cracking mechanisms. Comprehensive analyses were conducted on soil properties including physical characteristics, hydrophysical behaviors, chemical composition, and microstructural features. Simulated cracking experiments under natural environment were performed in laboratory settings, with quantitative characterization of soil cracking characteristics achieved through Matlab software. The results indicate that archaeological sites in arid environments are predominantly characterized by mud cracks, which primarily affect site presentation, while those in humid environments develop wider and deeper fissures that critically endanger structural stability. Soil particle composition and mineralogical constituents were identified as predominant factors governing cracking susceptibility, with moisture content variation serving as the triggering condition. Notably, elevated clay content, particularly montmorillonite concentration, significantly enhances cracking potential. The hydrophysical properties and microstructural characteristics essentially reflect the combined effects of particle and mineral compositions. Laboratory simulations successfully replicated field-observed cracking patterns, with Matlab quantification revealing the highest crack ratios at Sujialong and Hebosuo sites. Consequently, preliminary soil property analysis is recommended during early excavation phases to predict desiccation-induced structural responses, thereby preventing collapse caused by soil cracking.