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Compaction shall be in accordance with the requirements of subsection 203.10.

The Engineer will make measurements of test holes at random during progress of the work to determine the depth of uncompacted layers required to produce the designated nominal depth of base after compacting to the specified density.

Cutting of the test holes and refilling with materials properly compacted shall be done by the Contractor under the supervision of the Engineer.

Method of Measurement 304.07 The quantity to be paid for will be the number of cubic yards measured in the vehicles, or tons of material, including all filler, placed, compacted, and accepted in the completed course or placed in authorized stockpiles.

Scale weights of base course material may be adjusted for daily average moisture contents, in accordance with subsection 109.01.

The measurement of base quantities will not include any chemical additives paid for as a separate pay item.

When slag and stone (or gravel) are designated as alternative materials for pay items in the bid schedule and payment is by weight, the estimated quantities will be based on assumed average bulk specific gravities of available alternative materials. No adjustment in contract unit price will be made for variation in quantity due to differences in the specific gravity of the material actually used.

Water added to the materials will be measured by the M G. (1,000 gallons), by means of calibrated tanks or distributors or by means of accurate water meters furnished by the Contractor, if a bid item therefor is included in the bid schedule.

Chemical additives will be measured by the ton. If sacked additives are used, the net weight as packed by the manufacturer will be used for measurement.

Basis of Payment 304.08. The quantities, determined as provided above, will be paid for at the contract price per unit of measurement for each pay item listed below that is shown in the bid schedule, which price and payment will be full compensation for the work of this section with the following exceptions:

(a) Aggregate base course material, ordered by the Engineer, placed and left in stockpiles for future use will be paid for under section 413.

(b) Clearing and grubbing pits and quarries will be paid for in accordance with section 201.

(c) Roadbed preparation will be included under the work of section 207. Payment will be made under: Pay item

Pay unit 304(1) Gravel base, grading

Cubic yard. 304 (2) Gravel base, grading

Ton.
304(3) Crushed aggregate base,
grading

Cubic yard.
304(4) Crushed aggregate base,
grading

Ton.
304(5) Furnishing and applying calcium
chloride, type

Ton.
304(6) Furnishing and apply hydrated
lime

Ton.
304(7) Furnishing and applying sodium
chloride

Ton.

Ton. 304(8) Water for aggregate base course M G. Letter suffixes will be added to the item numbers for crushed aggregate base to designate alternative types of materials to be bid on by weight.

Section 305.-SUBGRADE MODIFICATION

Description

305.01 This work shall consist of scarifying the roadbed and the incorporation of aggregate and additives if required, into the scarified roadbed, or the addition and mixing of aggregate with materials obtained from the ditches and shoulder slopes, and the compaction of the mixture in reasonably close conformity to the nominal depth shown on the plans; also the realigning of the shoulders and the cleaning and reshaping of the ditches if called for on the plans.

Materials

305.02 Aggregate. Aggregate for subgrade modification shall conform to subsection 703.18 for the grading shown in the bid schedule.

Aggregate may be accepted at the point of production based on periodic production samples, subject to the provisions of clause 10 of the General Provisions.

305.03 Chemical Additives. Chemical additives shall meet the requirements of the following subsections: Calcium Chloride

712.02 Sodium Chloride

712.02 Hydrated Lime

712.03

Construction Requirements

305.04 Processing. If required by the plans, the shoulder slopes and ditches shall be bladed sufficiently to form a shoulder and ditch line in reasonably close conformity to the cross section shown on the plans. The material so obtained and the surfacing material existing on the road surface shall be spread uniformly over the roadbed. All weeds, sod, grass, roots, or other objectionable material obtained from the shoulder slopes and ditches shall be removed from the surface. If necessary to provide the required depth of subgrade modification, the roadbed shall be scarified to the necessary depth or additional material hauled in from designated locations. All material shall be thoroughly mixed and pulverized until not more than 5 percent of the material, exclusive of gravel or stone, is retained on a 2-inch sieve. The material so mixed shall be placed in a uniform windrow.

The quantity of aggregate for subgrade modification, as designated on the plans, shall be placed, windrowed, and brought to a uniform section. The windrowed materials shall be blended together until all materials are uniformly distributed throughout the combined windrow.

If required, chemical additives shall be uniformly distributed and thoroughly mixed with the windrow.

Sufficient water shall be added during the mixing operation to provide the moisture necessary for compaction.

The material shall then be spread uniformly to the required cross section and compacted to a density not less than 95 per cent of the maximum density determined in accordance with AASHO T 180, Method D. Field density tests will be made as provided in subsection 203.10. Rolling shall be accompanied by sufficient blading to assure a smooth surface.

305.05 Finishing and Curing. If a base or surface course is included in the contract, the surface of the completed subgrade shall be satisfactorily maintained until the base or surface course has been placed. If required, additional water shall be applied to prevent checking or raveling.

Method of Measurement

305.06 Aggregate for subgrade modification will be measured by the cubic yard or ton in accordance with Section 109—Measurement and Payment. Moisture in the aggregate will be deducted in accordance with subsection 109.01, if provided in the special provisions. When slag and stone (or gravel) are designated as alternative materials for pay items in the bid schedule and payment is by weight, the estimated quantities will be based on assumed average bulk specific gravities of available alternative materials. No adjustment in contract unit price will be made for variation in quantity due to differences in the specific gravity of the material actually used.

Water will be measured by the M G. (1,000 gallons) by means of calibrated tanks or distributors or by means of accurate water meters furnished by the Contractor. Only that water which is used in mixing materials or applied as ordered by the Engineer to keep the surface moist will be measured for payment.

Chemical additives will be measured by the ton. If sacked chemical additives are used, the net weight as packed by the manufacturer will be used for measurement.

Processing for subgrade modification will be measured by the station or by the mile as indicated on the plans and shall include all blading of ditches and shoulders, if called for on the plans; the scarifying and pulverizing of the existing surface; all placing and mixing of materials on the road; the compacting of the materials; the finishing of the surface; and the maintenance of the completed surface if applicable.

Basis of Payment

305.07 The accepted quantities of Subgrade Modification determined as provided above will be paid for at the contract unit price bid per ton or cubic yard for aggregate for subgrade modification, per MG. (1,000 gallons) for water, per station or mile for processing, and per ton for chemical additives, which price and payment will be full compensation for the work of this section. Payment will be made under: Pay item

Pay unit 305(1) Aggregate for subgrade modification, grading

Cubic yard. 305(2) Aggregate for subgrade modification, grading

Ton. 305(3) Water for subgrade modification M G.

Pay item

Pay unit
305(4) Processing for subgrade modifica-
tion

Station.
305(5) Processing for subgrade modifica-
tion

Mile.
305(6) Calcium chloride, type

Ton. 305(7) Sodium chloride

Ton. 305(8) Hydrated lime

Ton. Letter suffixes will be added to the item numbers for aggregate to designate alternative types of materials to be bid on by weight.

Section 306.—RECONDITIONING ROADBED

Description

306.01 This work shall consist of reconditioning the surface of an existing road, cleaning and reconditioning the ditches, including culvert inlets and outlets, and shaping the shoulders, all in reasonably close conformity with the plans and these specifications, immediately prior to the application of a prime coat or to the placing of a base or surface course.

Construction Requirements

306.02 The road, including the shoulders, shall be scarified to the depth and width required, except as provided below. The scarified material shall be pulverized so that not more than 5 per cent of this material, exclusive of gravel or stone, will be retained on a 2-inch sieve. The pulverized material shall be moistened and compacted to the density as specified in subsection 305.04. Blading and watering of the surface, if ordered, shall be continued during the rolling operations.

Existing bituminous surface shall be scarified and pulverized until all lumps are reduced to a size not greater than 142 times that of the maximum size aggregate in the existing bituminous surface. The bituminous aggregate shall then be windrowed or otherwise conserved for further use in the work, if not incorporated and compacted in the roadbed.

The surface shall be satisfactorily maintained until the base or surface course has been placed. If required, additional water shall be applied to prevent checking or raveling.

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