Bins Loads

Silo and bin design is still largely an art because there is no rational and certain method to determine the loads exerted by the stored solid on the structure. In an attempt to rectify this situation, the American Iron and Steel Institute contracted with the writers to develop better bin design criteria. The work appears to be meeting with success. A new mathematical theory has been postulated: two different loading conditions have been identified—initial, which occurs on filling, and flow, which occurs on emptying—and the important transient effect of the switch from initial to flow has been evaluated. That effect explains the wide scatter of results measured by so many investigators. To date, design criteria have been developed for symmetric mass-flow hoppers. An example of design is given. The design data are now being expanded to mass-flow bins, i.e., to mass-flow hoppers with a cylindrical surcharge. At a future date it is hoped to expand them further to funnel-flow bins.