Definitions

Table 1 below contains definitions of abbreviations and acronyms used in this IDEA tool. Table 2 contains definitions of the four subgrade strength categories used in the PCN results presented for selected airports.

Table 1. Summary of acronyms and definitions.
Acronym	Definition
AAC	Asphalt over Asphalt Concrete
AC	Asphalt Concrete
ACN	Aircraft Classification Number
AGG	Aggregate
APC	Asphalt over Portland Cement Concrete
APMS	Airport Pavement Management System
APTech	Applied Pavement Technology, Inc.
ASR	Alkali-Silica Reactvity
ASTM	American Society for Testing and Materials
BIT	Bituminous
CL	Class
CTB	Cement Treated Base
CTS	Cold Tar Seal
EST	Estimate
FAA	Federal Aviation Administration
FOD	Foreign Object Debris
ft, FT	Linear Foot
HBP	Hot Bituminous Paving
HMA	Hot-Mix Asphalt
HMBP	Hot Mix Bituminous Pavement
ICAO	International Civil Aviation Organization
IDEA	Interactive Data Exchange Application
in, IN	Inches
L&T Cracking	Longitudinal and Transverse Cracking
lbs, LBS	Pounds
LTB	Lime Treated Base
LTD	Longitudinal, Transverse, and Diagonal
M&R	Maintenance and Rehabilitation
MTOW	Maximum Takeoff Weight
NPIAS	National Plan of Integrated Airport Systems
PCC	Portland Cement Concrete
PCI	Pavement Condition Index
PCN	Pavement Classification Number
PDC	Pavement Dressing Conditioner
PFC	Porous Friction Course
PMBP	Plant-Mix Bituminous Pavement
psi, PSI	Pounds per Square Inch
RCF	Repairing Crack Fill
RCS	Rubberized Crack Seal
sf, SF, SqFt	Square Foot
STAB/STB	Stabilized
STD	Standard
yrs, YRS	Years

Table 2. Definitions of PCN subgrade strength categories.
Subgrade Strength Category	Definition
A	High (k-value >= 442 psi/in OR CBR >= 13)
B	Medium (221 psi/in < k-value <= 442 psi/in OR 8 < CBR <= 13)
C	Low (92 psi/in < k-value <= 221 psi/in OR 4 < CBR <= 8)
D	Ultra Low (k-value <= 92 psi/in OR CBR <= 4)