The scope of work is the study and design of refinery infrastructures for country of Middle East. Specifically, the project is about steel structures (pipe racks) which support pipelines & cable trays at multiple levels, various equipment (like air-coolers etc) as well as staircases & platforms, which serve the accessibility from the personnel for operation and maintenance purposes. In detail, the height of the pipe racks varies from ~12m to ~20m, their width from 3m to ~8m (with one or two bays), their span from ~3.5m to ~17m and their total length ~24m έως ~600m (with expansion joints ~30m for thermal expansions). Pipe racks are made by steel profiles as per AISC and their foundations consist of single footings or footings with two pedestals from reinforced concrete as per ACI. The load evaluation, the dimensioning and check verification of all structures have been made according to the provisions of the American Code ASCE 10. The design of the steel structures was implemented at STAAD Pro software of Bentley company, whereas the base plates were designed at IDEA StatiCA.