Book excerpt: The 69th volume of the journal includes articles dedicated to the latest research results in properties and processing technologies of structural materials such as steel, polymers, and composites, analysis and design of sliding mode controllers and automation of centrifugal pumps, designing of geothermal heat exchangers, investigation of seismic behaviour of soil-based structure and analysis mechanics of river's sediments transfer in conditions of Wadi Skhirate, Morocco. The issue will be useful to specialists in mechanical engineering and construction.