SECTION 02231

AGGREGATE BASE COURSE

PART 1 GENERAL

SECTION INCLUDES

Aggregate base course.

Aggregate [roads] [, walks] [, driveways] [and] [parking areas].

RELATED SECTIONS

Section 02211 - Rough Grading: Preparation of site for base course.

Section 02223 - Backfilling:	Compacted fill under base course.

Section 02225 - Trenching: Compacted fill under base course.

Section [______-____________]:	Subbase.

Section [______-____________]:	[Timber] [Concrete] curbs.

Section 02513 - Asphaltic Concrete Paving: Finish asphalt surface course.

Section 02514 - Portland Cement Concrete Paving:	Finish concrete surface course.

Section [02516 - Asphaltic Block Pavers] [02517 - Stone Pavers] [02518 - Interlocking Concrete Pavers] [02520 -Brick Pavers]: Finish pavers.

Section [______-____________]: [Drains] [manholes] [and] [________] including frames.

Section 02921 - Landscape Grading: Soil fill at areas adjacent to base course.

REFERENCES

AASHTO Ml47-65 - Materials for Aggregate and Soil-Aggregate.

ASTM C136 - Sieve Analysis of Fine and Coarse Aggregates.

ANSI/ASTM D698 - Test Methods for Moisture-Density Relations of Soils and Soil-Aggregate Mixtures, Using 5.5 lb (2.49 Kg) Rammer and 12 inch (304.8 mm) Drop.

ANSI/ASTM D1557 - Test Methods for Moisture-Density Relations of Soils and Soil-Aggregate Mixtures Using 10 lb (4.54 Kg) Rammer and 18 inch (457 mm) Drop.

ASTM D4318 - Test Method for Liquid Limit, Plastic Limit, and Plasticity Index of Soils.

SUBMITTALS

Submit under provisions of Section [01300] [________].

Samples:	Submit [10] [____] lb. ([4.5 [____] kg) sample of [each type of] aggregate to testing laboratory.

PART 2 PRODUCTS

MATERIALS

Coarse Aggregate: Type [A] [____] specified in Section [________].

****** [OR] ******

Coarse Aggregate: AASHTO Ml47, Grade [A] [B] [C] [D] [E]; passing the No. 40 sieve with a liquid limit of not more than [25] [____]; a plasticity index of not more than [5] [____] in accordance with ASTM D 4318.

****** [OR] ******

Coarse Aggregate: [Angular, crushed] [Natural] [, washed] stone; free of shale, clay, friable materials and debris; graded [in accordance with ASTM C136] within the following limits:

Sieve Size	Percent Passing

2 inches (50 mm)	[100] [____]

1 inch (25 mm)	[95] [____]

3/4 inch (19 mm)	[95] [____] to [100] [____]

5/8 inch (16 mm)	[75] [____] to [100] [____]

3/8 inch (9 mm)	[55] [____] to [85] [____]

No. [4] [____]

([4.75] [____] mm)	[35] [____] to [60] [____]

No. [16] [____]

([1.18] [____] mm)	[15] [____] to [35] [____]

No. [40] [____]

([450] [____] micro m) [10] [____] to [25] [____]

No. [200] [____]

([75] [____] micro m)	[5] [____] to [10] [____]

Fine Aggregate: Type [C] [____] specified in Section [________].

****** [OR] ******

Fine Aggregate: Natural river or bank sand; [washed] free of silt, clay, loam, friable or soluble materials; and maximum of [____] percent organic matter.

Herbicide:	[________________].

PART 3 EXECUTION

EXAMINATION

Verify [subbase] [subgrade] has been inspected, gradients and elevations are correct, and are dry.

AGGREGATE PLACEMENT

Spread course aggregate over prepared base to a total compacted thickness of [____] inches ([____] mm).

Place course aggregate in [3] [____] inch ([75] [____] mm) layers and [roller] [________] compact.

Level and contour surfaces to elevations and gradients indicated.

Add small quantities of fine aggregate to coarse aggregate

as appropriate to assist compaction.

Compact placed aggregate materials to achieve [[____] lb/cu ft ([____] kg/cu m) dry density] [compaction to [95] [____] percent of its maximum dry density in accordance with [ANSI/ASTM D698] [ANSI/ASTM D1557].

[Add water to assist compaction.] If excess water is apparent, remove aggregate and aerate to reduce moisture content.

Use mechanical vibrating tamping in areas inaccessible to compaction equipment.

TOLERANCES

Flatness: Maximum variation of [1/4] [____] inch ([6] [____] mm) measured with 10 foot (3 m) straight edge.

Scheduled Compacted Thickness: Within [1/4] [____] inch ([6] [____] mm).

Variation from True Elevation: Within [1/2] [____] inch ([12] [____] mm).

FIELD QUALITY CONTROL

Field [inspection and] testing will be performed under provisions of Section [01400] [________].

Gradation of Aggregate: In accordance with ASTM C136.

Compaction testing will be performed in accordance with [ANSI/ASTM D698] [ANSI/ASTM D1557] and with Section [01400] [01410] [________].

If tests indicate Work does not meet specified requirements, remove Work, replace and retest at no cost to Owner.

Frequency of Tests: [________________].

END OF SECTION