Failures of Steel Silos for Grain Storage - Fortuity or Underestimated Risk

Abstract

<p>The paper describes and investigates several cases of failures of silos made from corrugated thin steel sheets which were delivered and assembled in Bulgaria by foreign companies</p><p>Two main patterns of failures which occurred in different times of the year and at different locations in Bulgaria have been analyzed. The first failure pattern is related to collapses of conical roofs made from profiled trapezoidal steel sheetings while the second pattern involves fracture of cylindrical corrugated silo walls. On-site visual investigation of the failed silos and numerical analyses simulating the loading and stress state at the pre-failure situations have been performed.</p><p>Based on the lessons drawn from the investigated silo failures recommendations for improved structural design of the corrugated steel silos are proposed with the aim to avoid similar failure situations in the future.</p>