Experimental Investigation on the Evolution of Soil Arching in Cohesive Soils Using a DIC Technique

This study conducted a series of trapdoor tests to investigate the soil arching effect in cohesive soils, which are commonly encountered in engineering practice but have not been previously investigated in the existing literature. A detailed discussion was proposed to explore the transformations of soil arching, particle movements, and stress redistribution occurring over the trapdoor. Comprehensive parametric studies were conducted, with a particular focus on trapdoor widths and filling heights, to analyze the effects of different influential factors on soil arching. An advanced digital image correlation (DIC) technique was employed to monitor the displacement field during the test. Through the combination of high-precision displacement nephograms and earth pressure values, the entire evolution process of soil arching was comprehensively revealed, including its initial appearance, gradual development, and stabilization. Typical fracture surfaces were observed in the tests, resulting in a significant discrepancy compared to the trapdoor tests conducted in cohesionless soils. The aforementioned research not only provides a deeper insight into how soil arching will evolve with varying influential factors but will also help engineers to better use the soil arching effect of cohesive soils in the design phase.