2213.01 DESCRIPTION.
This work consists of excavating the shoulder material, removing existing curb, removing existing flumes, and construction of the widened portions of base prior to placement of a surface course, seal coat, or another base course as a part of the contract in accordance with the contract documents:

2213.02 MATERIALS.
Materials used in construction of base widening shall meet the following requirements:

A. Base Material.

1. HMA Base Widening.
The mixture used for widening shall be specified on the contract documents and meeting requirements of Section 2203, as specified.

2. PCC Base Widening.
Article 2201.02 shall apply.

B. Primer or Tack Coat Bitumen.
Article 2303.02, E, shall apply to tack coat bitumen used for base widening.

2213.03 EQUIPMENT GENERAL.
Equipment shall meet requirements of Sections 2001, 2301, 2302, and 2303.

2213.04 WIDENING EQUIPMENT.
Widening equipment shall comply with Section 2001 and the following:

A. Trench Machine.
The excavation shall be made with a machine which can be operated in a manner so that the depth and width can be accurately controlled.

B. Compaction Equipment.
Article 2001.05, E, shall apply, except that other types of equipment may be used when it has been demonstrated that required compaction will be secured. The finish roller on the subgrade and on the final layer of widening shall be a self propelled, smooth, steel tired roller.

C. Field Laboratories.
Section 2520 shall apply.

2213.05 REMOVAL OF CURB.
When specified in the contract documents or directed by the Engineer, the Contractor shall remove all integral curb by methods which will not damage the concrete that is to remain.

The curb shall be removed by grinding, or other method approved by the Engineer to provide substantially complete removal of curb that extends above the pavement surface and a reasonably safe and smooth surface to accommodate traffic. These may include sawing and breaking, chipping, or use of detonating cord explosive. When removal is by sawing and breaking, the work shall be done as shown in the contract documents and as follows:

A vertical saw cut shall be made along the edge of the curb nearest the center line of pavement. At the end of the curb section, the saw cut shall be extended to the extreme end of the curb, and at this point a saw cut shall be made at right angles and extended to the pavement edge. Where flumes occur in curb sections, the saw cut shall be extended across the throat of the flume. On resurfaced pavement, the saw cut shall be located 7 1/2 inches (190 mm) from the pavement edge, and it shall be to a depth of 3 inches (75 mm) below the surface of the resurfacing.

Immediately before breaking the curb, the sawed groove shall be cleaned and made free of dirt, stones, or any foreign matter to a depth at least 1 inch (25 mm) below the pavement surface.

Concrete, including resurfacing concrete and concrete across the throats of flumes, shall be removed to substantial compliance with the dimensions shown. All reinforcement exposed and loosened shall be cut off.

The Contractor shall clean up broken concrete in accordance with Article 1104.08. This broken concrete shall become the property of the Contractor.

2213.06 REMOVAL OF FLUMES.
When removal of flumes is required, removal shall be in accordance with Section 2514.

2213.07 PREPARATION OF SUBGRADE.
The subgrade for base widening shall be in accordance with Article 2302.07 with the following exceptions:

The width of trench cut for the widening shall be equal to the width of the widening shown in the contract documents. If the existing pavement is HMA, the edge of old asphalt, if any, shall be sawed or trimmed to a reasonably vertical line flush with the edge of the old concrete, or at the Contractor's option, this trim line may be made at any uniform distance in from the edge of the old concrete, not to exceed 3 inches (75 mm).

For HMA base widening, the edge of the old pavement shall be tack coated at a rate of 0.10 to 0.15 gallon per square yard (0.4 to 0.7 L/m²) in accordance with Article 2303.03, B, 2, and a waiting period will not be required before placing the widening.

2213.08 CONSTRUCTION.
The contract documents will show the total thickness of base widening to be placed.

A. HMA Base Widening.
The mixture shall be spread in the number of layers required to produce the required thickness. The compacted thickness of the top layer shall not exceed 2 inches (50 mm). The maximum compacted thickness of lower layers may exceed 3 inches (80 mm) if demonstrated that the thicker layers have satisfactory compaction and riding characteristics within reasonably close conformance to that expected from a layer 3 inches (80 mm) in thickness. Base material shall not be dumped on the surface of the old pavement, and any base material that is spilled thereon shall be removed immediately by brooming.

The width of spread shall be such that, after compaction, the constructed width conforms to the designed dimension.

Each layer shall be promptly and thoroughly compacted. Compaction shall be to the density specified in Article 2303.03, E, for Class IC compaction.

The percent of compaction will be based on the density obtained in the laboratory for that day's mixture.

Succeeding layers of base material may be placed as soon as the previous layer has been compacted. Density samples shall be taken from the compacted material and tested in accordance with Article 2303.04.

When the contract for base widening does not include resurfacing, the final surface of widening shall be flush with, or not more than 1/8 inch (3 mm) below, the surface of the old pavement.

The widening shall not be opened to traffic until it has cooled sufficiently to provide stability.

B. PCC Base Widening.
PCC base widening shall be in accordance with Article 2302.08 and the following exceptions:

1. Concrete Filler.
All depressed areas from which curb has been removed shall be cleaned and filled with PCC of the same composition as the concrete used for widening. Cleaning shall be by a stream of water or air under sufficient pressure to remove all loose and foreign material from the groove. Immediately before concrete is placed, the old concrete surface shall be sprinkled with water and covered with a thin layer of dry Portland cement which shall be broomed thoroughly into the surface. The filler shall be placed at the same time the adjacent widening is placed. Concrete for the filler shall be thoroughly tamped into place.

The filler shall be finished and cured as provided for the widening.

2. Curing.
If asphalt surface is a part of the contract, a dark colored curing compound may be used.

3. Joint.
Joints need not be sealed for PCC base widening.

2213.09 LIMITATION OF OPERATIONS.
When full depth repair patches are part of the contract, this work shall be done before the base widening is placed.

Unless the road is closed, the work of constructing base widening shall be performed on only one side of the pavement at a time. Widening on one side shall be open to traffic before curb on the opposite side is removed.

Traffic shall be permitted to use the pavement during construction operations, and all operations shall be conducted to provide a minimum of inconvenience to traffic.

Articles 1107.08, 1107.09, and 2303.03, D, shall also apply.

2213.10 MAINTENANCE OF BASE.
The Contractor shall be responsible for maintenance of the completed base widening prior to and during subsequent construction activities.

2213.11 WINTER SEAL.
All HMA base which is not covered with upper base or surface in the same construction season in which it is built shall be primed, as specified, and in addition, the Engineer may require an application of a winter seal. The winter seal shall consist of the bituminous material used as the primer or tack coat applied at 0.12 gallon per square yard (0.5 L/m²) and a sand cover applied at 10 to 15 pounds per square yard (5 kg/m² to 8 kg/m²), in accordance with Section 2307.

Winter seal required by the Engineer will be paid for as provided in Article 1109.03, B.

Except where road closure is provided in the contract documents, traffic will be allowed to use the road from the time construction is stopped until work is resumed the following season. Any repairs to the base required when construction is resumed shall be made by the Contractor at no additional cost.

2213.12 REBUILDING SHOULDERS.
Article 2302.09 shall apply.

2213.13 SAMPLES.
Articles 2303.04, D, 2, and 2301.34 shall apply.

2213.14 METHOD OF MEASUREMENT.

A. Removal of Curb.
The quantity of curb removed, in stations (meters), to the nearest foot (meter), will be the quantity shown in the contract documents.

B. Removal of Flumes.
The quantity of flumes removed will be the quantity shown in the contract documents.

C. Excavation, Class 13, for Widening.
The quantity of trench excavation for Base Widening will be the quantity shown in the contract documents as Class 13 excavation.

D. Base Widening.

1. Hot Mix Asphalt Base Widening.

a. Measurement by Weight (Mass).
The quantity of Hot Mix Asphalt Mixture for Base Widening will be determined in accordance with Article 2303.05, A, 1.

b. Measurement by Area.
The quantity of Hot Mix Asphalt Mixture for Base Widening, of the depth specified, will be determined in accordance with Article 2303.05, A, 2.

2. Portland Cement Concrete Base Widening.
The quantity of Portland Cement Concrete for Base Widening, of the depth specified, will be the quantity shown in the contract documents.

E. Asphalt Binder.
Article 2303.05, B, shall apply.

F. Primer or Tack Coat Bitumen.
Article 2303.05, E, shall apply.

G. Samples.
Article 2303.05, H, shall apply for HMA base widening. Article 2301.34, I, shall apply for PCC base widening.

2213.15 BASIS OF PAYMENT.

A. Removal of Curb.
The Contractor will be paid the contract unit price for Removal of Curb per station (meter).

B. Removal of Flumes.
The Contractor will be paid the contract unit price for Removal of Flumes per each unit.

C. Excavation, Class 13, for Widening.
For the number of cubic yards (cubic meters) of Class 13 excavation for trench excavation stated in the contract, the Contractor will be paid the contract unit price per cubic yard (cubic meter). This payment shall include removal of bituminous fragments, boulders, and broken concrete in accordance with Article 1104.08.

D. Base Widening.

1. Hot Mix Asphalt Base Widening.

a. Measurement by Weight (Mass).
The Contractor will be paid the contract unit price for Hot Mix Asphalt Mixture for Base Widening in accordance with Article 2303.06.

b. Measurement by Area.
The Contractor will be paid the contract unit price for Hot Mix Asphalt Mixture for Base Widening, of the depth specified, in accordance with Article 2303.06.

2. Portland Cement Concrete Base Widening.
The Contractor will be paid the contract unit price for Portland Cement Concrete for Base Widening, of the depth specified, per square yard (square meter).

E. Asphalt Binder.
Article 2303.06, B, shall apply.

F. Intentionally left blank.

G. Samples.
HMA base widening samples will be paid for in accordance with Article 2303.06, F. PCC base widening samples will be paid for in accordance with Article 2301.35, I.