About the author  ⁄ Aaron Gordon, P.E

Aaron Gordon is a Structural Engineer at Kimley-Horn in Dallas, TX, with a focus on public infrastructure projects. (aaron.gordon@kimley-horn.com)

Pedestrian and multi-use trail bridges have become more popular as public and private entities invest in alternative modes of transportation, human-scale design, and user safety. The design of these structures is typically adapted from vehicular bridge design methodology. While the scale of pedestrian bridges simplifies portions of the analysis, such as considering multiple lanes and certain load combinations, it adds several wrinkles, including vibration and increased attention to lateral loads. The American Association of State Highway and Transportation Officials (AASHTO) LRFD Guide Specifications for the Design of Pedestrian Bridges (AASHTO Pedestrian Bridge Guide) addresses these design aspects unique to pedestrian structures. Its use is strongly recommended by AASHTO’s Load and Resistance Factor Bridge Design Specifications (AASHTO LRFD) when designing pedestrian bridges and other structures not carrying full highway loading. In fact, a recent survey of state bridge offices found that over 90% of states explicitly require the use of the AASHTO Pedestrian Bridge Guide when designing such facilities in their jurisdiction. Despite a guide specification dedicated to pedestrian bridges, evaluating wind load on these structures involves consulting and cross-referencing various specifications based on different analysis methods. The indirect approach to wind loading makes it difficult for engineers to ensure appropriate design procedures are followed and fails to provide consistent reliability across the industry. This article reviews the evolution of wind load criteria, examines current wind load criteria for pedestrian bridges, and provides a path towards establishing a consistent design methodology for wind loading on pedestrian bridges.

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