Inadequate consideration for maintenance during design was recognized some years ago in the Iowa Highway Maintenance Study (1959--1960, HRB Special Report 65). The problem persists to this day and is a contributing cause of increased maintenance work and inconvenience to highway users.

A process is needed for designers to be systematically aware of the maintenance implications of their designs. Designs must be developed and evaluated, recognizing a number of assumptions affecting maintenance operations and requirements. Knowing the implications of these assumptions will permit the documentation of maintenance needs to ensure that maintenance personnel, equipment, materials, and funds will be available when needed.

Designers must also be aware of design details that create maintenance problems and be willing to incorporate improvements to increase the "maintainability" of highway components. There is a need to specifically identify and communicate maintenance problems that can be addressed through better design. This need is gaining importance because of the greatly increased volume of traffic that makes it difficult to close traffic lanes for routine maintenance work. Although it would be desirable to design highway components (such as pavements, bridges, drainage features, and roadside appurtenances) with zero-maintenance requirements, this is not usually possible; therefore, designs should be developed to ensure maintainability at minimum life-cycle costs.

Accordingly, research was undertaken to address three objectives: (1) determine the current practice of incorporating maintenance concerns in the highway design process and identify successful techniques, weaknesses, and needed improvements; (2) recommend a design process that will achieve explicit recognition of the maintenance implications of designs; and (3) list and describe design details that create maintenance problems and suggest improvements to overcome them. These objectives have been accomplished through a research approach that involved a literature search, a survey of practices, interviews in selected state transportation agencies, and a demonstration.

The research results have been published as NCHRP Report 349, "Maintenance Considerations in Highway Design."