2.6 — Strength of pavements Besluit toezicht luchtvaart BES
Strength of pavements
2.6.1 The bearing strength of a pavement shall be determined.
2.6.2 The bearing strength of a pavement intended for aircraft of apron (ramp) mass greater than 5700 kg shall be made available using the aircraft classification number – pavement classification number (ACN-PCN) method by reporting all of the following information:
a) the pavement classification number (PCN);
b) pavement type for ACN-PCN determination;
c) subgrade strength category;
d) maximum allowable tire pressure category or maximum allowable tire pressure value; and
e) evaluation method.
Note – If necessary, PCNs may be published to an accuracy of one-tenth of a whole number.
2.6.3 The pavement classification number (PCN) reported shall indicate that an aircraft with an aircraft classification number (ACN) equal to or less than the reported PCN can operate on the pavement subject to any limitation on the tire pressure, or aircraft all-up mass for specified aircraft type(s).
2.6.4 The ACN of an aircraft shall be determined in accordance with the standard procedures associated with the ACN-PCN method as indicated in the Aerodrome Design Manual Part 3.
Note – The standard procedures for determining the ACN of an aircraft are given in the Aerodrome Design Manual, Part 3. For convenience several aircraft types currently in use have been evaluated on rigid and flexible pavements founded on the four subgrade categories in 2.6.6 b) below and the results tabulated in that manual.
2.6.5 For the purposes of determining the ACN, the behavior of a pavement shall be classified as equivalent to a rigid or flexible construction.
2.6.6 Information on pavement type for ACN-PCN determination, subgrade strength category, maximum allowable tire pressure category and evaluation method shall be reported using the following codes:
a) Pavement type for ACN-PCN determination: | | Code
Rigid pavement | R
Flexible pavement | F
Note – If the actual construction is composite or non-standard, include a note to that effect (see example 2 below).
b) Subgrade strength category: | Code
High strength: characterized by K = 150 MN/m3 and representing all K values above 120 MN/m3 for rigid pavements, and by CBR = 15 and representing all CBR values above 13 for flexible pavements. | A
Medium strength: characterized by K = 80 MN/m3 and representing a range in K of 60 to 120 MN/m3 for rigid pavements, and by CBR = 10 and representing a range in CBR of 8 to 13 for flexible pavements. | B
Low strength: characterized by K = 40 MN/m3 and representing a range in K of 25 to 60 MN/m3 for rigid pavements, and by CBR = 6 and representing a range in CBR of 4 to 8 for flexible pavements. | C
Ultra low strength: characterized by K = 20 MN/m3 and representing all K values below 25 MN/m3 for rigid pavements, and by CBR = 3 and representing all CBR values below 4 for flexible pavements. | D
c) Maximum allowable tire pressure category: | Code
High: no pressure limit | W
Medium: pressure limited to 1.50 MPa | X
Low : pressure limited to 1.00 MPa | Y
Very low: pressure limited to 0.50 MPa | Z
d) Evaluation method: | Code
Technical evaluation: representing a specific study of the pavement characteristics and application of pavement behavior technology. | T
Using aircraft experience: representing a knowledge of the specific type and mass of aircraft satisfactorily being supported under regular use. | U
Note – The following examples illustrate how pavement strength data are reported under the ACN-PCN method.
Example 1 – If the bearing strength of a rigid pavement, resting on a medium strength subgrade, has been assessed by technical evaluation to be PCN 80 and there is no tire pressure limitation, then the reported information would be: PCN 80 / R / B / W / T
Example 2 – If the bearing strength of a composite pavement, behaving like a flexible pavement and resting on a high strength subgrade, has been assessed by using aircraft experience to be PCN 50 and the maximum tire pressure allowable is 1.00 MPa, then the reported information would be: PCN 50 / F / A / Y / U
Note – Composite construction.
Example 3 – If the bearing strength of a flexible pavement,resting on a medium strength subgrade, has been assessed by technical evaluation to be PCN 40 and the maximum allowable tire pressure is 0.80 MPa, then the reported information would be: PCN 40 / F / B / 0.80 MPa /T
Example 4 – If a pavement is subject to a B747-400 all-up mass limitation of 390 000 kg, then the reported information would include the following Note
Note – The reported PCN is subject to a B747-400 all-up mass limitation of 390 000 kg.
2.6.7 Aerodrome operators shall establish criteria to regulate the use of a pavement by an aircraft with an ACN higher than the PCN reported for that pavement in accordance with 2.6.2 and 2.6.3.
Note – Attachment A, Section 19 details a simple method for regulating overload operations while the Aerodrome Design Manual, Part 3 includes the descriptions of more detailed procedures for evaluation of pavements and their suitability for restricted overload operations.
2.6.8 The bearing strength of a pavement intended for aircraft of apron (ramp) mass equal to or less than 5700 kg shall be made available by reporting the following information:
a) maximum allowable aircraft mass; and
b) maximum allowable tire pressure.
Example: 4000 kg/0.50 MPa.
- Regeling
- Besluit toezicht luchtvaart BES
- Soort
- AMvB-BES
- Geldend vanaf
- 01-01-2021
- BWB-id
- BWBR0028721
- Versie
- 2021-01-01_0