RESEARCH PAPER
A semi-empirical equation to predict filling wall pressures on oblique conical hoppers
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Buildings, Infrastructures and Projects for Rural and Environmental Engineering (BIPREE), ETSIAAB, Universidad Politécnica de Madrid, Spain

Final revision date: 2022-07-22

Acceptance date: 2022-08-08

Publication date: 2022-09-26

Corresponding author
Francisco Ayuga

Int. Agrophys. 2022, 36(4): 285-295

HIGHLIGHTS
• Finite Element Model to predict the wall pressures on oblique hoppers
• Outlet circumferential location and eccentricity are the pressure main factors
• A semi-empirical equation is proposed to estimate pressures on oblique hoppers
KEYWORDS
TOPICS
ABSTRACT
Hoppers are frequently used in steel silos, especially in farm facilities and food industries. These structures occasionally have an oblique hopper with an eccentric outlet to improve the flow of material during discharge. The 2006 version of the European standard EN 1991-4 uses classical Walker theory to predict wall pressures on concentric hoppers, but oblique hoppers are not considered. The authors have developed a Finite Element Model to predict the wall pressures on oblique hoppers and several sensitivity analyses have been made to study the possible influence of different parameters including outlet eccentricity, the outlet circumferential position, the aspect ratio of the silo and hopper, and different stored materials. The results show that the circumferential location and eccentricity of the outlet are the main factors affecting the pressures on oblique hoppers. A semi-empirical equation is proposed to estimate the expected pressures on oblique hoppers which is designed to match with the maximum normal pressure obtained from the simulation, and to provide a good representation for the circumferential distribution of normal pressures. The results of this research may be of interest with regard to the upcoming revised version of the European standard EN 1991-4.
FUNDING
This work was supported by the Spanish Agencia Estatal de Investigación via the research project “Study of the structural behaviour of corrugated wall silos using Discrete Element Models (SILODEM)” [grant number PID2019-107051GB-I00/AEI/10.13039/501100011033], (2020-2023).
CONFLICT OF INTEREST
All authors declare no conflict of interest.

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