VIRGINIA
DEPARTMENT OF TRANSPORTATION
SPECIAL
PROVISION FOR
RIDEABILITY
June 24, 1998
Section
315.07(a) Surface Tolerances is replaced by
the following:
(a) Pavement smoothness will be determined
by a profiler on designated lanes having a design speed of 40 miles per hour or
higher as specified herein.
Intersections, urban areas, transition lanes, and pavement within 25
feet of bridge approach slabs will be tested by a straightedge.
For all
designated pavement, the surface course ride quality acceptance shall be based
on the lowest site average International Roughness Index (IRI) produced by a
minimum of two (2) test runs, in accordance with the requirements ASTM E 950
and reported for each lane. The South Dakota
style road profiler will measure International Roughness Index (IRI) of both
wheelpaths with laser height sensing instruments. The Department shall conduct the testing within 14 calendar days
of completion of the final surface course over the designated section(s).
Acceptance
An IRI number
in inches per mile shall be established for each 0.1 mile section and each lane
of the surface course. The last 0.01 mile section before a bridge, the first
0.01 mile section after a bridge, and the beginning and end 0.01 mile sections
of the surface course will not be subject to a pay adjustment
Areas excluded
from testing by the profiler will be tested using a 10 foot straightedge. The variation of the surface from the
testing edge of the straightedge between any two contacts with the surface
shall not be more than 1/4 inch. Humps
and depressions exceeding the specified tolerance shall be subject to
correction as directed by the Engineer, at no additional cost to the
Department.
The following
table provides the acceptance quality rating scale of pavement based on the
final rideability determination. The
pay incentive/disincentive schedule will be applied to the final surface area
of the surface course. The surface
area, in square yards, shall be calculated based on the tested section length
and lane width as shown on the plans.
INTERNATIONAL
ROUGHNESS INDEX
INCENTIVE/DISINCENTIVE
(INCHES PER MILE)
PAY ADJUSTMENT
(DOLLARS
PER SQUARE YARD)
50.0 AND UNDER 0.16
incentive
50.1 - 55.0 0.13
incentive
55.1 - 60.0 0.10
incentive
60.1 - 70.0 0.00
70.1 - 80.0 0.03
disincentive
80.1 - 90.0 0.10
disincentive 90.1 - 100.0 0.17 disincentive
OVER 100.0 SUBJECT TO CORRECTIVE ACTION
In addition,
any 0.01 mile of a 0.1 mile section that has a IRI which exceeds 110 inches per
mile will also be subject to correction as directed by the Engineer regardless
of the IRI average over that 0.1 mile section.
This 0.1 mile section will not receive any incentive payment. The
Engineer has the option of applying up to the minimum percent payment to any
0.1 mile section subject to corrective action or to any 0.1 mile section
containing a 0.01 mile section subject to corrective action.
When
corrections to the pavement surface are required, the Contractor's method of
correction shall be approved by the Engineer.
In order to produce a uniform cross section, the Engineer may require
correction to the adjoining traffic lanes or shoulders. Corrections to the pavement surface and/or
the adjoining traffic lanes and shoulders will be at no cost to the Department.
Where
corrections are made, the pavement will be retested to verify that corrections
have produced the acceptable ride surface.
Pay disincentives or corrections may be required based on the retested
IRI measurements. Retesting of a
corrected pavement surface will be at the Contractor's expense. No incentives will be provided for sections
on which corrective actions have been required.