Flexible Intermediate Bulk Containers (FIBCs), or “Bulk Bags,” are widely used across industries for the transport and handling of bulk materials. They provide clear advantages—lightweight construction, compact storage, dust-free discharge, antistatic options, and cost-effectiveness—making them an attractive alternative to traditional storage and handling systems. However, unlike rigid bins, silos, or stockpiles, which have been extensively studied, FIBCs present unique challenges. Predicting discharge behaviour and preventing blockages remain difficult due to their flexible walls, and existing bulk solid handling theories have not been entirely extended to this class of containers.
This report reflects on the second year of the project and details the progress made in understanding FIBC behaviour. Key advances include experimental testing with a scaled rig, comprehensive pressure measurements, and Discrete Element Method (DEM) modelling and validation for different material sets. Findings to date show that FIBCs behave fundamentally differently from conventional rigid containers, with distinct discharge mechanisms, flow regimes, and stress states. These insights underscore the need for new frameworks to better characterise and predict FIBC performance and provide a foundation for future experimental programs and modelling efforts as the project advances.