Design criteria for structural design of silage silo walls

Existing Swedish design guidelines (JBR) cover silo wall heights up to about 3 m. These guidelines presumably overestimate the forces and pressures exerted by silage juice when silo walls are more than 3mhigh, which could result in over-sizing, material waste and increased capital costs. This study determined silage physical properties in terms of horizontal wall pressure and evaluated silage juice levels in silos with a wall height of 3mormore.
New guidelines are proposed based on the results and on the Eurocode for ultimate limit states (ULS) for two stages; filling and the utility period. The design bending moment for ULS was 21% lower than specified in JBR.

Project funding: The project was funded by Swedish Board of Agriculture, Alnarp Partnership, Swedish Rural Economy and Agricultural Societies (Malmohus County, Sweden) and the Swedish Farmers Accident Insurance Fund.

Project time period: 2010 - 2013

Project leader: Hans von Wachenfelt.
Other associates: Christer Nilsson, Göran Östergaard, Anders Olofsson and Marie Karlsson.

Publications:
von Wachenfelt H, Nilsson, C., Östergaard G, Olofsson A, Karlsson M 2014. Design criteria for structural design of silage silo walls. Biosystems Engineering 126, 92-103.

Wachenfelt, H. & Nilsson, C. 2012. Beräkningsunderlag för hållfasthetsdimensionering av väggar till plansilor för ensilage - pressvattennivåer
(Design criteria for structural design of silage silo walls – silage juice levels). SLU, Lantbrukets byggnadsteknik, Alnarp. Intern rapport.

Wachenfelt, H., Nilsson, C., Östergaard, G., Olofsson, A. & Karlsson, M., 2013. Beräkningsunderlag för dimensionering av plansiloväggar
(Design criteria for structural design of silage silowalls). SLU Institutionen för biosystem och teknologi, Alnarp. LTJ-rapport 2013:16