921CONCRETE MEDIAN PAVING

1099 including furnishing and placing all needed aggregate base, Portland cement concrete, joint filler and curing compound and all incidental excavation except such excavation of roadway material as is to be paid for as part of the construction of the roadway subgrade on which the aggregate base is to be placed. SECTION 921 CONCRETE MEDIAN PAVING: 921- 1 Description: The work under this section shall consist of furnishing aggregate base, joint filler, and Portland cement concr ete, and constructing median paving at the locations and in accordance with the detailed requirements shown on the plans and in the specifications. 921- 2 Materials: 921- 2.01 Portland Cement Concrete: Portland cement concrete shall conform to the requirements of Section 1006 of the specifications for Class B concrete. 921- 2.02 Aggregate Base: Aggregate base shall conform to the requirements of Subsection 303- 2 of the specifications for class 1, 2, or 3 as specified therein. 921- 2.03 Joint Filler: Joint filler shall conform to the requirements of Subsection 1011- 6 of the specifications. 921- 2.04 Curing Compound: Curing shall be accomplished by any of the methods specified in Subsection 1006- 6.01 of the specifications, except that any method that may permanently discolor the concrete shall not be used. 921- 3 Construction Requirements: The surfaces upon which the base material is to be placed shall be fine graded and compacted to a density of not less than 95 percent of the maximum density as determined in accordance with the requirements of the applicable test methods of the ADOT Materials Testing Manual, as directed and approved by the Engineer. TABLE OF CONTENTS INDEX 1100 Aggregate base shall be compacted to a density of not less than 95 percent of the maximum density in accordance with the requirements of the applicable test methods of the ADOT Materials Testing Manual, as directed and approved by the Engineer. The final surface need not be finished with a leveling device. The base and adjacent back of curb shall be watered immediately in advance of placing concrete. Concrete shall be placed and thoroughly consolidated by means of approved mechanical vibrators or by tamping or spading by hand. The fresh concrete shall be struck off so the surface will be at the proper elevation when the concrete is consolidated. Finish on the slab shall be a transverse coarse broom finish. Expansion joints shall be constructed at a maximum of 60 foot intervals. Expansion joints shall be constructed between abutting structures, around poles, posts, boxes, and other fixtures that protrude through the median paving. Expansion joints shall match as nearly as possible the expansion joints in the adjacent pavement or curb. Joint filler shall be placed vertically and extend full depth beginning 3/16 inch below the surface of the concrete being placed. During the placing and tamping of concrete, the filler shall be restrained in its proper position. Contraction joints (weakened- plane joints) shall be constructed at a maximum of 15 foot intervals and shall coincide with contraction joints in adjacent pavement or curb. A contraction joint shall be constructed longitudinally when the width of the concrete exceeds 15 feet. The concrete shall be scored for a depth of 1 inch transversely. Immediately following the required finishing operations, all exposed surfaces shall be cured as specified in 1006- 6. Before acceptance of the work, all median paving shall be cleaned of all discolorations resulting from the contractor 's operations, including, but not limited to, dirt, stains, bitumens, and equipment tire marks. Cleaning may be by abrasive blast methods or by other methods approved by the Engineer. 921- 4 Method of Measurement: Quantities of concrete median paving will be measured by the square yard of concrete placed. 921- 5 Basis of Payment: The accepted quantities of concrete median paving, measured as provided above, will be paid for at the contract unit price per square yard. The price shall include full compen sation for the work complete in place, including furnishing and placing all needed aggregate base, Portland cement concrete, joint filler and curing compound and all incidental excavation. TABLE OF CONTENTS INDEX 1101 SECTION 922 UTILITY CONCRETE FOR MISCELLANEOUS CONSTRUCTION: 922- 1 Description: The work under this section shall consist of furnishing all materials, mixing and placing Portland cement concrete for post foundations and anchors for barrier fences, line fences, chain link fences and miscellaneous signs; concrete foundations for depth gauges at fords; concrete for right -of-way markers and survey monuments; concrete rings at ground surface for irrigation valves and gates; concrete fill at the base of electrical pull boxes; and for similar uses as specified on the project plans or in the Special Provisions. 922- 2 Materials: Portland cement, water, admixture, fine aggregate and coarse aggregate shall conform to the requirements of Section 1006 of the specifications. The coarse aggregate size designation shall be chosen by the contractor and be approved by the Engineer and shall conform to the size designation and gradation requirements of AASHTO M 43. 922- 3 Construction Requirements: The Engineer will inspect and approve the facilities, materials, and methods for producing the concrete to insure that concrete of the quality suitable for use in the work will be obtained. Mixing and placing of the concrete shall conform to the requirements of recognized practice. Concrete may be mixed in mobile mixers upon approval of the Engineer. Mixing and placing concrete in cold weather shall conform to the requirements of Subsection 1006- 5.03 of the specifications. There is no maximum temperature limitation for the concrete mixture immediately prior to placement. The minimum cement content per cubic yard of concrete shall be 470 pounds. If approved by the Engineer, the contractor may substitute commercially available sacks of redi -mix concrete, suitable for the intended purpose. Should such substitution be approved, the cement content specified herein and the requirements of Subsection 922- 2 of the specifications shall not apply. All exposed concrete shall be finished to a smooth surface. 922- 4 Method of Measurement: No measurement will be made of the concrete used. TABLE OF CONTENTS INDEX