Microstructure and hydro-mechanical behaviour of compacted granular bentonite

In recent years, granular bentonite GB has become a reference material since it facilitates the backfilling operation due to high-density compacted granules with extended grain size distribution(maximum sizes around 10 mm). This investigation explores initial microstructure of MX80-type and hydro-mechanical HM response observed at phenomenological scale. Samples were statically fixed dry density (1.55 Mg/m3 ), encompassing wet sides optimum. Themicrostructural study was performed using combination X-ray micro-computed tomography mercury intrusion porosimetry. The results indicate that pore function can be simplified as double-porosity network micropores (intra-granular/aggregate pores) macropores(inter-granular/aggregate pores). Compacting side increases macropores, making sample more compressible on loading under as-compacted states despite higher matric suction. time evolution swelling pressure displays double-peak pattern attributed particular samples. Moreover, does not significantly influence water retention properties without marked hysteresis in high-suction range confined wetting/drying cycles. work’s outcomes highlight microstructure’s significance behaviour provide further insight into geotechnical this material.