Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology
A.W.F. Corver Drukberekening in silo's met flexibele wanden. Een evaluatie van nieuwe berekeningsmethoden. Literature survey, Report 98.3.TT.5106, Transport Engineering and Logistics.
Most existing studies of silo wall pressures were performed on stiff-walled silos, so existing design equations may give poor predictions of pressures in flexible silos. Almost all existing methods do not consider any interaction between the stored material pressure and the wall deformation.
The goal of this study is to examine whether it is possible to make better predictions of pressures in flexible silos by taking into consideration the combined action of the stored material and the wall.
In this study the following recent attemps to predict wall pressures in flexible silos are examined:
The finite element analysis (J.Y. Ooi and J.M. Rotter Wall pressures in squat steel silos from simple finite element analysis, Computers ans Structures, Vol.37 No.4 (1990), pp.361-374).
The Modified Janssen Theory for flexible circular silos (Y.T. Feng and Y.L. Hua Modified Janssen thory for flexible cicular bins, Journal of Structural Analysis, Vol.122 No.4 (April 1996), pp.454-456).
The String Theory (M. Kaminski and E. Wirska Interpretation of pressure and displacement measurements of flexible silo walls using string theory, Bulk Solids Handling, Vol.18 No.2 (1998)).
It is shown that both the Modified Janssen Theory and the finite element analysis give better results in calculating wall pressures in flexible wall silos. The Modified Janssen theory is more convenient in terms of practical usage. In practice, the horizonal wall pressure can be about 20% smaller than the wall pressure of the rigid-walled case.
Reports on Transport Engineering and Logistics (in Dutch)
