Pavimentos

Airfield uses of asphalt

1. Introduction
Most of the world's paved roads are surfaced with asphalt, which gives good performance and durability under the most heavily trafficked conditions. Asphalt mixes are also widely used in the construction of hard standing and parking areas for both light and heavy vehicles. They are therefore eminently suitable for use inthe construction andsurfacing of access roads, perimeter roads and vehicle parking areas on airfields.

Asphalts give good performance and durability under the wide range of climatic and traffic conditions. More and more often asphalts are used for industrial areas or for specific applications, such as base courses for railway tracks. Asphalt is also widely used in airport construction, although this usage is notalways recognised. A recent survey resulted in the following data on its usage on airfields:

Table 1

This shows that a majority of airports are in fact constructed with asphalt pavement. This document gives information and examples about the type of asphalt used. In airports, there are different areas such as runways, taxiways, aprons and parking areas. For each, the requiredspecifications could be different particularly for surface courses. For parking and aprons, good resistance is needed to puncturing, to fuel and to chemical agents. For other surfaces, a good skid resistance is necessary. Asphalt mixes provide the answerto these various requirements.

In addition to these uses, asphalt mixes are widely employed in the surfacing of runways and aircraft handlingareas on a wide range of airfields, from international airports regularly used by the heaviest airliners, through military airfields carrying high performance jet aircraft and the smaller domestic airfields regularly used by light or medium-sized aircraft to the smallest private airfield used by light single or twinseat aircraft.

In Europe, the construction and surfacing of military airfields isthe responsibility of the each nation’s Defence Ministry, whilst responsibility for the civil airports usually rests with the civil or municipal aviation authorities. These organisations often have their own standard specifications for this type of work.

2. General considerations

Without hard paving, access may be difficult to the airfield, flying may be restricted in inclement weatheror the facilities may not come up to the minimum standards required by the regulatory authorities for passenger carrying. The following areas on a typical airfield are likely to require hard paving:

* runways
* taxi-ways providing access to runways
* aircraft parking, re-fuelling or servicing aprons hanger floors
* car, bus or commercial vehicle parking areas
* access roads.Airfield uses of asphalt

In each of these areas different considerations apply. For example, runways require good skid-resistance and surface water drainage for good braking while avoiding aquaplaning, an even surface regularity to ensure passenger comfort and minimum risk of damage to delicate electronic components and adequate strength to support the high wheel-loadings ofmodern aircraft. Where jet-engined aircraft operate, freedom from looseparticles on the surfacing is an additional, essential requirement to avoid the expensive damage that can be caused to jet engines from ingestion of foreign objects (known as Foreign Object Damage or FOD).
For aircraft parking areas the main requirement is adequate stability under high wheel-loadings; for paved areas whereaircraft will undergo re-fuelling and servicing, the principal considerations are adequate stability under wheel-loads and heavy point loads from maintenance machinery as well as good resistance to oil and fuel spillage.

Asphalt mixes can be very suitable for some of these applications but less suitable for others. Proprietary surfacings have been developed for situations where traditional...