01515130

Component

The Aircraft Classification Number/Pavement Classification Number (ACN/PCN) method has been adopted as the standard method for reporting airfield pavement bearing strength since 1980's. Recently, the Federal Aviation Administration (FAA) developed an advisory circular to provide specific guidance on PCN determination. Even though the new airport pavement design approach using the FAARFIELD design software have been approved, "the pavement thickness requirements associated with the ACN-PCN procedures are based upon historical procedures identified in previous versions of AC 150/5320-6". The thickness mode for rigid pavements in the latest COMFAA 3.0 program still uses the FAA Westergaard method. The primary objectives of this study are to investigate its fundamental principles, the reasoning of the new revisions, and the effects on PCN determination. The original development of ACN/PCN methodology was first reviewed. The newly revised approach using cumulative damage factors for computing PCN based on equivalent traffic was also discussed. A Visual Basic Application (VBA) module was added to the conventional design spreadsheet (R805FAA) by executing the COMFAA 2.0 program iteratively to automatically determine the PCN value. The existing TKUAPAV program was recoded into an Excel spreadsheet with additional VBA modules to facilitate automatic PCN calculations using both R805FAA's bilinear fatigue relationship and PCA's fatigue equation. Revisions to the existing ACN/PCN calculation procedure have been made and implemented in the above spreadsheet based on four different failure models and two different critical stress models (edge or interior). A standard aircraft with a dual wheel main gear load of 90,000 lbs was introduced in this study to expedite critical aircraft conversions for PCN calculations. The potential problems of the existing procedures and the benefits of the proposed revisions are compared and illustrated through different case studies. Attempts to simplify ACN/PCN definitions are proposed and discussed.

This paper was sponsored by TRB committee AFD10 Pavement Management Systems. Alternate title: Development of Simplified Pavement Classification Number Approach for Reporting Rigid Airfield Pavement Bearing Strength.

01503729

14-2551

English

13p

2014

Transportation Research Board 93rd Annual Meeting

Digital/other

References; Tables

Airport runways; Bearing capacity; Case studies; Pavement design; Rigid pavements; Thickness

Excel (computer program); Visual Basic

Pavement classification number

Aviation; Pavements; I22: Design of Pavements, Railways and Guideways

Transportation Research Board Annual Meeting 2014 Paper #14-2551

TRIS, TRB, ATRI

Jan 27 2014 2:53PM