Page 296 - Planning and Design of Airports

CHAPTER 7

Structural Design of

Airport Pavements

Introduction
This chapter briefly describes various methods for designing airfield
pavements. The term structural design of airport pavements as used in
this text refers to the determination of the thickness of the compo-
nents that make up an airfield pavement structure, rather than the
design of pavement materials itself.
Airfield pavement is intended to provide a smooth and safe all-
weather riding surface that can support the weights of such heavy
objects as aircraft on top of the natural ground base. Airfield pave-
ments are typically designed in layers, with each layer designed to a
sufficient thickness to be adequate to ensure that the applied loads
will not lead to distress or failure to support its imposed loads. The
Federal Aviation Administration provides guidance on the design
of airfield pavements within its Advisory Circular AC 150/5320-6E,
Airfield Pavement Design and Evaluation. Originally published in 1975,
this advisory circular was completely revised in 2008 to consider new
design methods that are based on recently developed computer soft-
ware models and appropriate for the heaviest of commercial air car-
rier aircraft. This chapter provides both an account of the historical
pavement design and evaluation methods and details the current
method of pavement design and evaluation. As with any element of
airport planning and design, appropriate Advisory Circulars and
software user guides should be studied and referenced prior to perform-
ing any airport pavement analysis. These resources may be down-
loaded from the FAA at http://www.faa.gov.
Pavement or pavement structure is a structure consisting of one or
more layers of processed materials. A pavement consisting of a
mixture of bituminous material and aggregate placed on high-
quality granular materials is referred to as flexible pavement. When
the pavement consists of a slab of portland cement concrete (PCC),
it is referred to as rigid pavement. Both structures of pavement are

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