The Aesthetic Design of Pedestrian Bridges: An Engineer's Perspective

Abstract

The process of designing a pedestrian bridge starts by identifying project objectives that have to be met within the project constraints. Project objectives are translated into functional, structural and aesthetic requirements. Functional requirements include bridge width, plan alignment, vertical profile, drainage system, railing dimensions and lighting. Structural requirements include providing sufficient strength and durability, complying with deflection criteria, and preventing excessive vibrations. The aesthetic goals are more difficult to quantify, however, as they are frequently stated in terms of satisfying the desires of the local community or creating a landmark structure of symbolic character. There are a wide variety of possible project specific constraints. General constraints include construction budget and schedule, environmental issues, geotechnical and hydraulic considerations, availability of materials, local construction practice and experience. Many of the objectives and constraints affecting pedestrian bridge projects are also common to roadway or railroad bridge projects. However, the fact that pedestrian bridges need to be built to fit the human scale and are often located in an urban environment makes aesthetic considerations much more relevant. Bridge designers, like design professionals in other fields, are confronted with the challenge of incorporating aesthetic goals into a complex set of functional requirements, structural considerations, and project constraints while keeping costs within budget.