Vertical Pressures and Compressive Friction Force in a Large Silo

Abstract

The grain flow is a dynamic phenomenon of high non-linearity, responsible for the occurrence of a high index of structural problems in silos, assuming particular interest in Brazil because the country does not have a standard of design of these structures. In order to determine the transfer of loads to the foundations, a silo in true magnitude was instrumented through pressure cells in the reinforced concrete slab of the bottom and through load cells under two of its column. The experiment was conducted during the period from December 2016 to February 2017 in Entre Rios do Oeste-PR. The profiles of vertical and the compression friction pressures were obtained during the loading, storage and unloading phases of corn grains. The vertical pressure distribution in the silo bottom was shown to be variable along its radius, in accordance with the formulation of the AS 3774 standard, an alternative to the simplified uniform distribution hypothesis prescribed by the EN 1991-4 and ANSI/ASAE EP433 standards. We also observed experimentally the non-occurrence of overpressure at the unloading of the silo under analysis. The load transfer coefficient to the column was 0.35, being that the ANSI/ASAE EP433, EN 1991-4 and AS 3774 standards increased this transfer by 6.57%, 35.91% and 75.03% respectively, reflecting the great divergence between these prescriptions.

Increasing of strength-rigidity parameters of bases of metallic silos

“…Ensuring of reliability and safety of operation of metallic silos with the goal of decreasing of foundation settlements is topical both for new building and for objects already brought into operation [1][2][3][4][5] . Taking into account requirements of effective land legislation to efficient land management, new building is planned on plots unsuitable for agriculture.…”

Features of structures and calculation of steel spiral-fold silos

“…The development of these progressive structures is constrained by the lack of studies of the stress-strain state of these shells because these structures have a folding lock. A number of domestic and foreign scientists have been engaged in the analysis of structures, calculation methods and experimental studies of cylindrical shells of metal silos for strength and stability [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. Mileykovsky et al [5] in their work presented a computational model of the shell in the form of a scan of a cylindrical surface, which is considered as a ribbed plate with inclined edges.…”

Pressões em silo armazenador de produtos pulverulentos alimentícios a partir da norma Eurocode 1

“…De acordo com estudos Ding (2014) e Fank et al (2018), as pressões que ocorrem durante a descarga não são perfeitamente entendidas, levando-se em conta que a pressão no início da descarga é muito próxima da pressão no final da descarga. Também pode ser notada uma discrepância existente entre a pressão calculada e a medida experimentalmente na extremidade superior da tremonha.…”