Steel Silo Failures Due to Design Errors

Steel silos are very common structures used to store granular bulk solids in various industries worldwide. These special non-building structures are subjected to unconventional loading conditions and may lead to failure if not designed properly. Sometimes, failure only involves distortion or deformation of silo components. In other cases, failure of a silo can be a disastrous structural collapse resulting in material loss and contamination, possible damage to the environment, and in extreme cases loss of life. In many cases, insurance claims and lawsuits follow, exacerbating the burden already carried by all the parties involved in the failure. Failures in steel silos often occur due to the following reasons: design errors, construction errors, improper usage, and/or lack of maintenance. In this paper, we will discuss steel silo failures due to design errors. Silo design requires specialized traits, which includes knowledge of stored material behavior and loads exerted on the silo walls. How these loads interact with the entire structural system is normally not well understood at the design stage. At the same time, there is not enough guidance available in the adopted building codes and standards for the design of steel silos, which often leads to inadequate designs. Engineers in charge of the design and construction of silos will benefit from this paper through a better understanding of the structural implications of silo design as well as the loads imposed by the stored material. Forensic engineers will be able to identify areas of distress in steel silos caused by different loading scenarios commonly observed in silo structures. This will help them to provide a more comprehensive evaluation while investigating the structural damage and/or failures in steel silo structures.