DESCRIPTION

This Special Provision modifies the surface tolerance requirements and the pay adjustment factors specified in section 550.04 P. of the North Dakota Department of Transportation 1997 Standard Specifications for Road and Bridge Construction.

GENERAL

The pavement smoothness will be determined using a Cox CS8200 computerized profilograph, with a data filter setting of 2.0. The profile of the finished surfaces of the mainline pavement will be measured with the profilograph, using a 0.00 inch blanking band.

Each days paving will be tested the following day. The Engineer and Contractor will use the results of the testing to evaluate the paving methods and equipment, also to provide the smoothest possible pavement.

Excluded from profilograph testing are:
· Bridge Decks.
· Shoulders.

· Ramps.

· Tapered sections.
· Individual sections of pavement less than 50 feet in length.

· The first (or last) 15 feet of a pavement section where the Contractor is not responsible for the adjoining surface.

On surfaces excluded from profilograph testing, the Engineer will determine the pavement smoothness using a 10 foot straightedge. The Engineer will select the locations to be tested. Variations in the surface that exceed 1/8", longitudinal or transverse, shall be ground with diamond grinding equipment as specified in Section 550. After the Contractor has corrected an irregularity, the Engineer will retest the area to verify compliance with the specified tolerance.

SURFACE TOLERANCES AND TESTING

The Contractor shall produce pavement with a profile index of 3.00 inches or less per 0.1 mile section. Pavement with initial profiles that exceed 3.00 inches per 0.1 mile section may be accepted after corrective measures by the Contractor have been completed.

The NDDOT will determine the pavement profiles for each lane according to the procedures for one lane, as specified in Section 550.04 P of the NDDOT Standard Specifications. Additional profiles may be taken to define the limits of an out-of-tolerance surface variation. The Contractor shall repair or replace any curing membrane or protective cover that is damaged or removed during the testing.

PAVEMENT SMOOTHNESS EVALUATION

The NDDOT will determine a profile index (inches / 0.1 mile) for each section of finished pavement surface. A pavement section is defined as a continuous area of finished pavement 0.1 miles in length and one lane (12.0 ft nominal) in width. A partial section resulting from an interruption of the continuous pavement surface (i.e. bridge approaches, the cessation of the daily paving operations, etc.) is subject to the same evaluation as a whole section.

The NDDOT will determine the profile index of the paving operation, grouped in even 0.1 mile sections. When a partial section remains, it will be added to the next days paving operation to maintain even 0.1 mile sections. If the production of the last day of project paving is less than 0.1 mile section, it will be added to the previous 0.1 mile section.

If the day's average profile index exceeds 4.50 inches / 0.1 mile, the paving operation will be suspended until corrective action is taken by the Contractor. When the paving is resumed, the paving operations will be evaluated with the initial testing procedures shown above.

CORRECTIVE ACTIONS

For determining pavement sections where corrective work or pay adjustments will be necessary, the pavement will be evaluated in 0.1 mile sections using the profilograph. Each individual profilograph trace will be evaluated (not the average of multiple traces) to determine the areas where corrective action is needed.

Within each 0.1 mile section, all areas representing high points (bumps) with deviations in excess of 0.3 inch in a length of 25 feet or less shall be corrected by the Contractor regardless of the profile index value.

Any 0.1 mile section, including bumps, having an initial profile index between 3.01 and 3.80 inches / 0.1 mile shall be corrected to reduce the profile index to 3.00 inches / 0.1 mile or less on each trace. Any 0.1 mile section, including bumps, having an initial profile index of 3.81 inches / 0.1 mile or greater shall be corrected to reduce the profile index to 3.00 inches / 0.1 mile or less on each trace, or replaced at the Contractor's option.

On sections where corrections are made, the pavement will be tested to verify that corrections have produced a profile index of 3.00 inches / 0.1 mile or less for each trace.

(3) Corrections shall be made using diamond grinding equipment or by removing and replacing the pavement. Bush hammers or other impact devices will not be permitted. Where surface corrections are made, the Contractor shall establish a uniform texture the full width of the lane, but transverse grooving will not be required. Corrective work shall be at the Contractor's expense and shall be completed prior to determining pavement thickness.

PAY ADJUSTMENT

Unit bid price adjustment will be paid only when both adjacent 12-foot driving lanes meet the indicated surface smoothness. To qualify for bonus payment, each lane must have a measured profile index of less than 3.00 inches per 0.1 mile for five or more consecutive 0.1 mile increments and an average International Roughness Index (IRI) of less than 50.0 inches per mile in the driving lane for five or more consecutive 0.1 mile segments. The IRI will be determined by the average of three passes with NDDOT's Class III Response Type Roughness Measurement System. The IRI will be measured after completion of the concrete paving. A length of 25feet on each side of each transverse construction joint (header) will be exempted from the profile index determined with the profilograph. The bonus payment will apply to the total area of the ½ (0.5) mile or more segment (two lanes, 24feet wide) minus the exempted areas at the headers. No bonus will be paid in any segment if there is any grinding outside of the exempted areas.

If a header exemption area has a deviation in excess of 0.3 inch per 25feet, the Contractor shall remove the high points with a diamond grinding device.

Unit bid price adjustment will apply to the total area of the 0.1 mile segment of pavement, for the lane width represented by the profile (12 feet wide). A paving section less than 0.1 mile shall be added to the subsequent day's paving operation to total 0.1 mile.

SCHEDULE FOR ADJUSTED PAYMENT

Profile Index Contract Price
inches per 0.1 mile Adjustment
(greater than 45 mph) per 0.1 mile
section per lane

1.00 or less +$995.00
1.01 to 1.5 +$745.00
1.51 to 1.80 +$370.00
1.81 to 3.00 $ 0.00
3.01 to 3.80 $ 0.00*
3.81 or more -$625.00*

*Correct to 3.00 inches / 0.1 mile

SP 188(97)

Page of 3

Revised October 25, 1999

SP 188(97)
Page of 3
Revised October 25, 1999