Methodology of Applying Heavy Weight Deflectometer for Calculation of Runway Pavement Classification Number

The International Civil Aviation Organization requires every airport that serves commercial airline operations to publish its pavement classification number (PCN) in its own aeronautical information publication. This number is defined as a number expressing the bearing strength of a pavement for unrestricted operations. Likewise, each airline must provide the aircraft classification number (ACN) that corresponds to each type of aircraft it operates. Only when the aircraft's ACN is less than the airport's PCN is the aircraft allowed to land with its maximum landing weight. Otherwise, the aircraft is restricted to a certain weight limit. There are two ways to determine the PCN: the using aircraft method and the technical method. Many airports chose to determine the PCN by the using aircraft method because of its simplicity. However, the technical method, which can specify the pavement structural bearing capacity more accurately, can give a more precise PCN than the using aircraft method. An in-depth description of the establishment of a technical methodology for determining PCNs by applying the heavy weight deflectometer field data is presented. A practical case study of a runway with two kinds of slab thickness mixed with two types of subgrade strengths is introduced for calculating the PCN through the established methodology.