Late-stage development and evolution characteristics of surface desiccation cracking in sacrifice area of Sanxingdui site

To explore the development process of desiccation cracking in clay soil, the desiccation cracking deterioration on the surface of the archaeological site in sacrifice area of Sanxingdui Ruins site is taken as the research object. The long-term and in-situ monitoring of desiccation cracking development is conducted along the concurrent environmental data collection. The data analysis focuses on studying the evolution characteristics of desiccation cracking at the late stage of deterioration development, exploring the correlation between desiccation cracking development and the environment, and investigating the feasibility of the grouting method based on the temporal characteristics of desiccation cracking. The results indicate that the development of desiccation cracking includes both morphological evolution and dimensional changes. Specifically, some primary main fractures demonstrate continuous expansion slowly, while a minority of the secondary fractures intermittently extend or emerge. Overall, the width and depth of the primary main fractures gradually increase and become stable over time. Larger fractures exhibit more obvious size increments during development. The moisture content of the soil is the predominant environmental factor influencing the desiccation cracking. Change in the controlling factor results in different development stages of fractures at varying depths within the soil, leading to intersecting fractures that form fracture blocks, and under the stress adjustment, smaller fractures are suppressed from developing, resulting in spatial and temporal heterogeneity in change of fractures sizes. Practical experience has demonstrated the feasibility of relieving desiccation cracking deterioration through the grouting method at stable periods of desiccation cracking development.