Section 2121. Granular Shoulders.

2121.01 DESCRIPTION.
This work shall consist of preparing a shoulder area and furnishing and placing granular material on the prepared area as shown in the contract documents for Type A Granular Shoulders or Type B Granular Shoulders as specified. This section may also apply to construction of paved shoulder fillets.

2121.02 MATERIALS.
Shoulder material for Type A and Type B shoulders shall meet the following:

1. Crushed stone - Meeting the requirements of Article 4120.02.

2. Gravel/Limestone1 - Meeting the requirements of Article 4120.02.

3. Crushed Portland cement concrete2,3 - Meeting gradation 11 of Section 4109.

4. Crushed composite HMA and PCC2,3 - Meeting gradation 11 of Section 4109.

Note 1 - When the option is allowed in the contract documents.

Note 2 - Either salvaged or unclassified sources of material may be allowed.

Note 3 - Other quality requirements of Section 4120 will not apply.

The Engineer may disallow short sections of material substitutions and may restrict the substitution to both sides of the pavement.

Aggregate for paved shoulder fillets shall meet requirements of Article 4120.07.

RAP inspected in accordance with Article 2303.02, C, may be used for Type A and B Granular Shoulders. When this material is used for granular shoulders, it shall be processed so that 100% of the material passes the 1-1/2 inch (37.5 mm) sieve. When so processed, other gradation and quality requirements of Section 4120 will not apply.

Recycled crushed PCC, RAP, or crushed composite HMA and PCC may be uniformly blended with crushed stone. Recycled materials shall not total more than 30% of the shoulder aggregate for new construction and not more than 50% of the total for existing granular shoulders.

2121.03 EQUIPMENT.
The equipment shall meet requirements of Section 2001 and the following:

A. Trench Machine.
Excavation necessary to prepare the subgrade shall be a motor grader or other approved machinery.

B. Proportioning and Mixing Equipment.

1. Type A Granular Shoulders.
Proportioning equipment shall accurately proportion each material. For mixing and prewetting more than one aggregate, Article 2001.08, B, shall apply. For prewetting one aggregate or one premixed aggregate only, Article 2001.08, A, shall apply. A traveling mixer may be used where a road is closed to through traffic if it proportions water to a single or premixed aggregate and mixes the material in a single pass operation and achieves mixing equivalent to that required from a stationary mixer. Prewetting will not be required when the quantity of Type A granular shoulders designated for the contract is less than 2000 tons (2000 Mg).

Any mixing plant shall include a means of calibrating and adjusting the proportioning equipment, and provisions shall be made for a periodic check calibration.

2. Type B Granular Shoulders.
For Type B granular shoulders, proportioning, mixing, and prewetting equipment are not specified.

C. Equipment for Applying Water.
Article 2001.09 shall apply.

D. Compaction Equipment.
Article 2001.05, B and C, shall apply for compaction of granular shoulder material. Article 2001.05, D, shall also apply when the road or adjacent lane is closed to public traffic. Vibratory rollers, described in Article 2001.05, F, may be substituted for compaction, provided equivalent compaction is obtained and demonstrated to the Engineer. This equipment may also be used for compaction of earth fill.

When the thickness of a Type B shoulder is 3 inches (80 mm) or less and the width is not more than 3 feet (1 m), the coverages may be with loaded truck tires having a weight (mass) not less than 200 pounds per inch (3.5 kg/mm) of tire width. The surface of both types shall be finish rolled with one complete coverage by a steel tired roller.

E. Weighing Equipment.
Article 2001.07 shall apply.

2121.04 PROPORTIONING AND MIXING.
For Type A granular shoulders, when more than one aggregate is to be combined, they shall be mixed before delivery to the road. Except as permitted in Article 2121.03, B, the aggregate shall be premixed with sufficient water, acceptable to the Engineer, so the mixture will readily compact. Water shall be uniformly distributed throughout the material so that all particles are uniformly wetted.

For Type B granular shoulders, the aggregate shall be in a moist condition so that it will readily compact. Article 2001.08 shall not apply.

2121.05 SURFACE PREPARATION.
For Type A granular shoulders, the surface shall be prepared by one of the following methods:

A. Earth Shoulder Fill.
This work involves construction of a shoulder fill to such elevation below that of the pavement edge as to allow for placement of granular shoulders as shown in the contract documents. Material shall be select treatment materials of Article 2102.06, A, 1, if available and coordinated with the Engineer, or suitable soils of Article 2102.06, A, 2. Material shall not be unsuitable soils of Article 2102.06, A, 3, or topsoil. It shall be spread and compacted in accordance with Articles 2107.04 and 2107.05 and shaped, smoothed, and finished. Deviations in elevation of the shoulder fill exceeding 0.05 foot (15 mm) shall be corrected. When unpaved side roads, drives, or entrances extend through the shoulder area, the side roads, drives, and entrances shall be excavated or filled with earth as necessary to provide a suitable approach and as directed by the Engineer.

Equivalent compaction with equipment specified in Article 2121.03, D will be acceptable.

B. Trenching and Reshaping.
The earth of the existing shoulder shall be removed to the width and depth shown in the contract documents. Existing vegetation shall be removed and deposited on the foreslope. Unless otherwise specified in the contract documents, excess excavated material shall be removed from the project. At driveways and intersecting roads which have fillets or pavement of a higher type, the shoulder shall not be excavated for placement of shoulders. Deviations in the elevation of the subgrade exceeding 0.05 foot (15 mm) shall be corrected. If necessary to backfill earth in preparing the subgrade, the backfill earth shall be thoroughly compacted by tamping or rolling in layers not exceeding 3 inches (80 mm) in depth.

For reshaping earth shoulders to the specified cross section adjacent to the granular shoulder, earth fill need not be rolled except for 1 foot (0.3 m) adjacent to the granular shoulder.

For Type B granular shoulders, minimum surface preparation work is anticipated. Existing shoulders damaged by the Contractor's operations shall be restored. Existing vegetation shall be removed and deposited on the foreslope. Bituminous edge rut material and existing aggregate shall be salvaged from the fillet area and deposited on the outer shoulder area. The work should assure a nearly vertical pavement edge.

If earth fill is anticipated, it will be designated in the contract documents, along with provisions for payment.

2121.06 CONSTRUCTION.
The aggregate shall be placed to width, thickness, and slope shown in the contract documents.

A. Type A Granular Shoulders.
Granular shoulder material shall be placed on the subgrade in such manner that no material is deposited on the adjacent pavement surface. If inadvertently spilled on the adjacent pavement, it shall be removed by shovels and brooms immediately.

The material shall be spread and compacted in such a manner that the finished elevation and width conform to the specified cross section.

Compaction shall be accomplished by six complete coverages with a pneumatic tired roller or a steel vibratory roller, followed by at least one complete finish coverage with a steel tired roller. The Engineer may reduce the rolling when unstable subgrade is encountered and may require additional finish rolling, if needed to ensure a satisfactory surface finish. Shaping shall be done concurrently with compaction. The tolerance for width of the completed shoulder shall be ± 0.2 foot (60 mm).

The required moisture content shall be maintained in the granular shoulder material until it has been satisfactorily spread, compacted, and finished to the required dimensions.

The Engineer will check the shoulder cross slope with a template furnished and used by the Contractor. The tolerance for shoulder cross slope shall not be less than or more than 1 percent greater than the slope specified.

B. Type B Granular Shoulders.
Granular shoulder material shall be deposited directly on the shoulder for the width designated and without being dumped on the pavement.

The moist aggregate shall be thoroughly compacted by a minimum of four complete coverages of the entire exposed surface with the pneumatic tired roller or a steel vibratory roller, followed by at least one complete finish coverage with a steel tired roller. Should the aggregate be so dry that, in the opinion of the Engineer, it will not readily compact, moistening will be required.

The aggregate shall be shaped to produce a smooth surface, flush with the pavement edge and tapered to meet the shoulders at the width shown in the contract documents.

C. Paved Shoulder Fillet.
The aggregate for a granular fillet at the edge of a paved shoulder shall be placed and compacted as provided in Article 1107.08.

2121.07 LIMITATIONS.
The following limitations apply:

A. Type A Granular Shoulders.
When traffic is to be maintained on adjacent pavement, the work of constructing granular shoulders shall be performed on only one side of the pavement at a time. All operations shall be conducted to result in a minimum of inconvenience to traffic. The portion of the shoulder excavated shall be filled with granular material and compacted prior to opening to traffic. The Engineer may modify this requirement for unusual and justifiable conditions. When the construction of the pavement is staged, construction of the granular shoulder shall also be staged, according to Article 2121.07, B. Granular shoulder material for temporary fillets shall be placed, moistened if necessary, and compacted according to Article 2121.06, B.

B. Type B Granular Shoulders.
When a drop-off is caused by the Contractor's operations and is adjacent to a lane open to public traffic, placement of granular shoulders shall be coordinated so that they are brought up to the pavement operation before the adjacent lane is opened to traffic. A fillet of granular material shall be used to temporarily correct a drop-off created by the resurfacing. If a fillet is placed, the minimum width of the fillet shall be 6 times the thickness of HMA resurfacing completed. This material shall be bladed across the shoulder prior to placement of the final layer of granular surfacing. The Engineer may modify this requirement for narrow shoulders and other justifiable conditions.

C. Winter Shutdown
Granular shoulder material shall be brought up to the pavement edge for the full width of the shoulder, at the design cross slope, prior to winter shutdown.

2121.08 METHOD OF MEASUREMENT.
The quantity of aggregate satisfactorily placed in granular shoulders of either type will be computed from the weights (mass) of individual truck loads, including moisture in the aggregate at time of delivery. Moisture added after delivery will not be measured for payment.

The quantity of Trenching and Reshaping, in stations (meters), will be the quantity shown on the contract documents. The quantity of Trenching and Reshaping will be determined for each side of the pavement or base.

2121.09 BASIS OF PAYMENT.

A. Type A Granular Shoulders.

1. Type A Granular Shoulders.
For the number of tons (megagrams) of Type A Granular Shoulder Material placed on the shoulder, the Contractor will be paid the contract unit price per ton (megagrams). This payment shall be full compensation for furnishing all materials, including aggregate and water, and for furnishing all equipment, tools and labor necessary to place the material in accordance with the contract documents.

The earth shoulder fill required in the shoulder area under the granular shoulder will be paid for separately.

When general traffic has not been routed through the work during paving or base construction but all or a portion of the work must be done under general traffic as provided in Article 2121.07, A, no payment will be made for additional flagging, barricading, decreased production or other items directly related to this traffic.

2. Trenching and Reshaping.
The Contractor will be paid the contract unit price for Trenching and Reshaping per station (meter). This payment shall be full compensation for trenching, reshaping, and removing excess excavated material from the project.

B. Type B Granular Shoulders.
For the number of tons (megagrams) of Type B Granular Shoulder Material placed on the shoulders, the Contractor will be paid the contract unit price per ton (megagram). This payment shall be full compensation for furnishing all materials, including aggregate and water, and for furnishing all equipment, tools, and labor to place the material in accordance with the contract documents. It is also full compensation for the minimum surface preparation work described in Article 2121.05.

The earth shoulder fill required in the shoulder area under the granular shoulder will be paid for separately.

Furnishing and placing the paved shoulder fillet adjacent to paved shoulders shall be considered incidental and will not be paid for separately.

The contract will have a separate item for Granular Shoulders, Place Only, of the type specified in tons (Mg), when the Contracting Authority is providing the material or if the material is available from mandatory crushing on the contract. The cost of crushing should be included in the Contractor's price for granular shoulders if recycling is not required but the Contractor chooses to crush the pavement removal for granular shoulder material.