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2303.1 REVISIONS, AMENDMENTS, AND CLARIFICATIONS

Revisions, amendments, and clarifications to ODOT Standard Specifications shall be included in the Special Conditions of the Contract. The ODOT section shall be referenced by number and description, followed by the required information.

2304 SPECIAL CITY REQUIREMENTS

2304.1 TESTING REQUIREMENTS

A. Materials Testing: Materials testing shall be as specified in the ODOT Standard Specifications.

B. Construction Testing: Testing of completed construction shall be as specified in the ODOT

Standard Specifications and Section 1006 of these specifications.

C. Tolerances: Tolerances shall be according to ODOT Standard Specifications except as modified herein.

1. Pavement Surface Thickness: Average test thickness shall not be less than the plan thickness, and no individual test thickness shall be deficient by more than 6.25 mm (1/4"). Maximum thickness to be averaged shall be no more than 12.5 mm (1/2”) greater than the design thickness. The asphalt pavement core thickness shall be measured according to ASTM D-3549-93a.

2. Concrete Compressive Strength: No individual test cylinder for 28 day compressive strength shall be less than the specified strength.

2304.2 SUBGRADE

A. Preparation:

1. When preparing the subgrade, all roots and plant material shall be removed and the excavation refilled with suitable backfill.

2. When working the subgrade all soft, yielding, or other unsuitable materials, shall either be removed and replaced, or stabilized in place.

3. The subgrade shall be constructed to grade by use of "blue tops". "Blue tops" shall be placed every 50 ft. at both the center line and at the back of curb and gutter. If lime, fly ash, cement etc. is added to the subgrade, the subgrade shall be "blue topped" before and after placement of the added material.

4. Dowels are required at all longitudinal and transverse contraction joints in concrete pavement which is 200 mm (8") thick or greater. Dowel size shall be reviewed and accepted by the City Engineer.

5. The entire subgrade shall be constructed to the required grade, density tests taken and reviewed, and proof rolling completed and reviewed, before construction of the curb and gutter or any other paving.

6. Subgrade shall be compacted to 95% standard proctor density at ± 2% of optimum moisture.

B. Stability Testing:

1. When preparing subgrades the subgrade will be checked for stability, even though it may meet the compaction requirements.

2. The check for stability shall be proof rolling with a large roller or loaded scraper and visual observation to insure that there is no pumping of the subgrade.

C. Correction of Unstable Subgrade:

1. A pumping subgrade shall be treated or replaced until it is stable.

2. Subgrade drainage shall be considered when a subgrade pumping problem is encountered.

When subgrade drainage is not installed, the engineer shall inform the City Engineer, in writing, of the reasons for not installing subgrade drainage.

3. Fly Ash: When used for subgrade stabilization, fly ash shall conform to ODOT 702.01, (ASTM C618) Class C.

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4. When Subgrade modification is required, such a lime, kiln dust , or fly ash, it shall be mixed and Processed According to the appropriate section of the latest edition of the Oklahoma Standard Specifications for Highway Construction as published by the Oklahoma Department of Transportation (ODOT). When lime is used, 5% will be the minimum percentage provided.

2304.3 BASE

A. Base Drainage: Where groundwater or surface water ponding present a threat to base stability a drainage system as shown in Standard Drawing ST 22 is recommended.

2304.4 CONCRETE PAVING

A. Concrete Street General:

1. Curb and gutter may be placed separate of the pavement.

2. Concrete shall be cured with white curing compound.

3. Joint layouts shall be reviewed by the City Engineer prior to placement of paving. If possible, longitudinal contraction and construction joints shall present logical traffic lanes to the driver.

4. Dowels are required at all longitudinal and transverse contraction joints in concrete pavement which is 200 mm (8") thick or greater. Dowels shall be 1¼” in diameter, 450mm (18") long spaced at 300mm (12") center to center.

B. Longitudinal Joints:

1. Longitudinal cracking joints shall be placed at intervals equaling two (2) times the pavement thickness in inches converted to feet (i.e. 2 X 6" = 12" which converts to a 12 foot spacing of longitudinal cracking joints) but, not to exceed every 15 feet.

2. Longitudinal construction joints on residential and residential collector streets may, at the option of the design engineer, be butt type joints with a tiebar or keyway type without a tiebar.

3. Longitudinal construction joints on all other streets shall be keyway type with a tiebar.

4. Longitudinal contraction joints shall be made to a minimum depth of one fourth (1/4) the thickness of the pavement.

C. Transverse Joints:

1. Transverse contraction joints shall be placed at intervals equaling two (2) times the pavement thickness in inches converted to feet (i.e. 2 X 6" = 12" which converts to a 12 foot spacing of transverse contraction joints) but, not to exceed every 15 feet.

2. Transverse construction joints on residential collector streets may, at the option of the design engineer, be butt type joints with a tiebar or keyway type without a tiebar.

3. Transverse construction joints on arterial streets shall be keyway type with a tiebar.

4. Transverse contraction joints shall be made to a minimum depth of one fourth (1/4) the thickness of the pavement.

D. Expansion Joints:

1. Expansion joints shall be placed at all street intersection radius and at the last joint before a cul-de-sac.

2. Expansion joints shall have a tiebar when the street being constructed requires a tiebar or

keyway for a construction joint.

2304.5 JOINT SEALING