ABSTRACT

Silo collapses have been reported around the world. Most of the collapses are due to a lack of continuous monitoring and inspections. Following years of deterioration, Silos become fragile structures, as a result, they become susceptible to imminent collapses. South Africa is no exception to this and recently a Silo collapse has been recorded. This paper proposes an extensive investigative approach to the structural assessment of Silos. The paper outlines a detailed methodology on a Silo investigation and the equipment used to collect the data. The first step involved capturing scientific data on-site, this included detailed visual inspection on the inside and outside of the Silo to determine crack patterns and other defects, this was achieved using high definition cameras, also a 3D scanner was used to establish the structure geometry. This was used to define the size of the Silo along with abnormalities such as deflected shape and buckling. A GPR was used to determine the rebar arrangement, cover thickness and Silo wall thickness. Concrete cores were collected for strength tests and carbonation. A corrosimeter was also used to determine the level of reinforcement corrosion. Finally, the data collected was input into a finite element analysis program. The Silo was analyzed for the current deteriorated state for applicable loading conditions using the Eurocode.