Wind Load Considerations for Existing Petrochemical Structures: Fid-Bau Portal

Wind Load Considerations for Existing Petrochemical Structures

Gilbert, Richard T. / Bailey, James R. / Rennalls, Norman / Young, Gregory B.

Engineers working in the petrochemical industry are commonly required to deal with changes and modifications to an existing facility. These changes and modifications must be recognized and evaluated for their impact on the existing equipment support structures and foundations. The updated ASCE report "Wind Loads on Petrochemical and Other Industrial Structures" provides references and suggested guidelines that should help the practicing engineer who is involved in an engineering evaluation of an existing structure or equipment foundation subject to extreme winds. The evaluation of existing structures for extreme wind loading should be approached differently than when designing new facilities. Conservative design loads and a conservative application of the design loads are common practices in the design of new petrochemical facilities, and this conservatism usually has minimal impact on the installed cost of the facility. But, this same conservatism in the evaluation of an existing structure or foundation could result in unnecessary upgrades and increased costs for the owner. The following sections provide guidelines, references and special considerations that should be used when evaluating wind loads on existing petrochemical structures and foundations, and the focus is on eliminating the conservatism associated with the design of new structures. The topics to be covered include the wind exposure category, the wind load combinations, special considerations for hurricane prone regions, and other considerations and that are unique to an evaluation of an existing structure, such as the potential for past modifications or deterioration of the structure. Finally, some references to model building codes that address modifications or additions to existing buildings or structures are provided.