TM 5-623
APPENDIX C
DEDUCT VALUE CURVES-ASPHALT SURFACED JOINTED CONCRETE PAVEMENT
Using figure C-1, find .64 on the distress density line.
C-1. Introduction
Proceed vertically to the M (Medium Severity) curve, then
In this appendix is furnished the deduct value curves
horizontally to the left to read a deduct value of 17.
essential for computing the PCI of a pavement sample
unit as used in the manual PAVER system (figs C-1
(3) For 50 square feet of distress type 15 (Rutting) Low
through C-40).
Severity, the density equals
C-2. Type of pavements
50 x 100 = 2.0.
The curves are provided in alphabetical order according
2500
to distress types, covering first asphalt surfaced
pavement, then concrete pavements.
Using figure C-15, find 2.0 on the distress density line.
Proceed vertically to the L (Low Severity) curve, then to
C-3. User instructions
the left to read a deduct value of 13.
As explained in chapter 3, the following five steps are
involved in calculating the PCI for a sample unit::
c. Step 3. A total deduct value is computed by
a. Step 1. Each sample unit is inspected and
summing all individual deduct values in the sample unit.
distress data recorded on DA Form 5145-R for concrete
or DA Form 5146-R for bituminous pavements.
d. Step 4. The corrected deduct value (CDV) is
b. Step 2. The deduct values are determined from
computed. In the example given in figure 3-3, the total
the deduct value curves in this appendix. The following
deduct value (the sum of all deduct values) was found to
examples are given for a sample unit 25 feet by 100 feet
be 45. The value of q (the number of individual deducts
(2500 square feet):
whose value is greater than 5) was found to be 2. Using
(1) For 6 square feet of distress type 1
figure C-20 find 45 on the TDV line. Proceed vertically to
(alligator cracking) low severity, the density equals
the line q equals 2, then to the left to read a CDV of 33.
6 x 100 =.24.
e. Step 5. The PCI is computed using the relation
2500
PCI = 100CDV. In the example, PCI= 100-33 = 67; the
rating is good.
Using figure C-1, find .24 on the distress density line.
Proceed vertically to the L (Low Severity) curve, then
C-4. Deduct value curves
horizontally to the left to read a deduct value of 4.
The deduct value curves and the corrected deduct value
curves provided in this appendix are needed to solve
(2) For 16 square feet of distress type 1
steps 2 and 4 above.
(Alligator Cracking) Medium Severity the density equals
16 x
100 = .64.
2500
C-1
Previous Page
