Performance-based design of steel towers subject to wind action

• Published in: Engineering structures Vol. 143; pp. 549 - 557
• Main Authors: Tessari, Rodolfo K., Kroetz, Henrique M., Beck, André T.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.07.2017; Elsevier BV
• Subjects: Design; Design engineering; Latticed telecommunication tower; Mathematical models; Minimum cost; Performance-based Engineering; Performance-based Wind Engineering; Philosophy; Probabilistic analysis; Probabilistic methods; Reliability analysis; Steel; Structural design; Structural engineering; Structural reliability; Studies; Telecommunications towers; Towers; Uncertainty; Wind effects; Wind engineering; Wind fields; Wind power; Brazil; Latticed telecommunication tower; Structural reliability; Performance-based Engineering; Probabilistic analysis; Performance-based Wind Engineering
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2017.03.053

•PBWE methodology applied to design of telecommunications steel tower.•Equivalent static and discrete dynamic wind load models lead to similar reliability.•Most unfavorable wind direction shown to be quite conservative.•Uneven recurrence intervals for distinct performance levels can guide optimum design.•Wind speed is the most relevant random variable. Performance-based Wind Engineering (PBWE) is a novel design philosophy that aims to identify and quantify the uncertainties involved in structural design, in order to ensure predictable performance levels to engineering structures. Due to the recent proposal of the methodology and formulation complexity, there are few studies related to PBWE, each presenting different limitations. This paper proposes an application of the Performance-based Wind Engineering methodology to the probabilistic analysis of steel towers, evaluating different calculation models for the estimation of wind forces on this type of structure. Uncertainties involved in the characterization of the wind field and the structural strength were investigated, and two procedures of the Brazilian winds standard NBR6123:88 for the estimation of wind forces on steel towers were analyzed. A case study concerning the reliability estimation of a telecommunication tower was also conducted. It was found that both studied calculation models lead to similar safety levels, and that the design of towers considering that wind always blows from the worst direction is too conservative. It is also shown that, in PBWE, minimum cost design can be guided by assigning same target reliability, but different mean recurrence intervals for different performance levels.