Influence of Moisture Content on Some Mechanical Properties of Wheat

The loads generated inside agricultural silos under static and dynamic conditions depend on the mechanical properties of the materials stored inside them. Silo calculation methodologies are based on these mechanical properties. Although it is known that moisture content greatly influences the values reached by these mechanical properties, only a few studies have been conducted to determine them. The present work determines the angle of internal friction, the apparent cohesion, the dilatancy angle and the apparent specific weight of wheat when subjected to different moisture contents. Direct shear and oedometer assay devices were used. In addition, a climatic chamber was used to moisten the wheat samples used in this work. From the different assays conducted, it could be observed that the values of the angle of internal friction, the apparent cohesion and the apparent specific weight were like those found in the literature. However, no values of the dilatancy angle of wheat as influenced by moisture content were previously reported. The values obtained here for this parameter are within the range of those specified for dry wheat samples. Finally, higher apparent specific weight values were observed as moisture content increased up to 13.4%, then decreasing at a moisture content of 15.5%. This was not expected according to the results stated by some authors, although others reported a similar tendency. The values here provided can be used in silo load calculations involving numerical methods for modeling technological processes.