Particle segregation is a widespread phenomenon in nature. Vertical vibration systems have been a focal point in studying particle segregation, providing valuable insights into the mechanisms and patterns that influence this process. However, despite extensive research on the mechanisms and patterns of particle separation, the consequences, particularly the mechanical properties of samples resulting from particle segregation, remain less understood. This study aims to investigate the segregation process of a binary mixture under vertical vibration and examine the consequences through monotonic and cyclic triaxial drained tests. The results reveal that large and small particles segregate nearly simultaneously, with more thorough separation observed for large particles. The segregation index, Ds, effectively describes this evolution process, offering a quantitative metric for both mixing and segregation. Granular temperature analysis unveils three distinct states during segregation: solid-like, fluid-like, and solid-liquid transitional phase, corresponding to varying activity levels of particle segregation. Drained triaxial shear tests demonstrate the sensitivity of stress-strain relationships to the degree of segregation. Interestingly, ultimate strength is found to be essentially unrelated to the degree of segregation. When the segregation index approaches zero, signifying particles approaching a uniform distribution, the granular system reaches a harmonic state. This state exhibits optimal mechanical performance characterised by maximum peak stress, friction angle, and the highest elastic modulus. These findings underscore the potential impact of segregation on the mechanical response of granular mixtures and emphasise the necessity of a comprehensive understanding of particle segregation in soil mechanics.

Particle segregation in the feeding system is a critical issue, leading to the nonuniform distribution of particles inside the flash smelting furnace and subsequently resulting in the production of unreacted materials. This study employs DEM to investigate the flow and segregation of concentrate particles in a scaled feeding system. The numerical simulations, based on calibrated parameters, are validated against two experiments, demonstrating good agreement. The influences of feeding rate, chute width, and sloping angle on particle segregation are analyzed. The severest segregation is obtained under the current operating parameter in metallurgical plants. Further increasing the feeding rate will not result in a continuous worsening of segregation. Notably, it is confirmed that increasing the chute sloping angle can largely reduce particle segregation. Meanwhile, segregation can also be reduced by narrowing the chute width; however, this leads to more particle accumulation at the periphery, potentially impacting subsequent dispersion within the furnace.

The fabric structure and dynamic behaviour of granular materials have been extensively studied in geotechnical engineering due to their considerable impact on permeability and mechanical properties. However, particle segregation, causing significant structural changes, remains inadequately understood, especially concerning its dynamic evolution in both global and local segregation processes. This study aims to investigate the motion of particles and evolution of internal microstructure in binary mixtures under vibrational conditions. The emphasis lies in comprehending both global and local time segregation processes, along with elucidating the potential underlying mechanisms. Through DEM simulations, it is observed that large particles tend to rise to the surface of the container while small particles aggregate at the bottom, resulting in the well-known Brazil Nut Effect. As the vibration intensity increases, the degree of segregation becomes more pronounced. Vertical segregation precedes radial segregation and eventually leads to stable separation of the binary mixture. To comprehensively analyse the segregation behaviour, we introduce a segregation index and reveal a correlation between vertical and radial segregation. Additionally, the ascending process exhibits characteristics similar to compressed solid blocks, while the descending process resembles fluid-like behaviour, suggesting a phase transition phenomenon during particle segregation. The study further highlights the role of pore filling and convective rolling as driving mechanisms for particle segregation. These findings emphasize the potential impact of external disturbances on the microstructure of granular mixtures, with implications for scenarios such as earthquakes, debris flows, and traffic loads.