Interlocked fabric of an in-situ sand in thick alluvial deposit and its micro scale mechanism

Key Points

• This research aims to clarify the microscale mechanisms influencing the mechanical properties of natural sand soils versus remolded sand soils.
• Compared frozen natural sand from sedimentary areas and remolded sand prepared by the rain method.
• Conducted hollow cylinder torsional shear tests and unconfined drying tests, plus X-ray tomography for structural comparison.
• Analyzed initial shear modulus and characteristics under monotonic loading and undrained cyclic loading conditions.
• Natural sand soil exhibits higher initial shear modulus and more pronounced dilatancy under monotonic loading; differences decrease with continued loading.
• In undrained cyclic loading, natural soil demonstrates higher liquefaction resistance.
• X-ray analysis indicates natural sand soil has greater average coordination number and contact area ratio compared to remolded sand, particularly in larger particles.