The publications listed below form a part of this specification to the extent referenced. The publications are referred to in the text by basic designation only.

For the purposes of this specification, the following definitions apply.

Aggregate base course (ABC) is well graded, durable aggregate uniformly moistened and mechanically stabilized by compaction.

Graded-crushed aggregate (GCA) base course is well graded, crushed, durable aggregate uniformly moistened and mechanically stabilized by compaction. GCA is similar to ABC, but it has more stringent requirements and it produces a base course with higher strength and stability.

Degree of compaction required, except as noted in the second sentence, is expressed as a percentage of the maximum laboratory dry density obtained by the test procedure presented in ASTM D 1557 abbreviated as a percent of laboratory maximum dry density. Since ASTM D 1557 applies only to soils that have 30 percent or less by weight of their particles retained on the 9.0 mm 3/4 inch sieve, the degree of compaction for material having more than 30 percent by weight of their particles retained on the 9.0 mm 3/4 inch sieve shall be expressed as a percentage of the laboratory maximum dry density in accordance with AASHTO T 180 Method D and corrected with AASHTO T 224.

The quantity of [ABC] [and] [GCA] completed and accepted, as determined by the Contracting Officer, shall be measured in square meters yards.

The quantity of [ABC] [and] [GCA] completed and accepted, as determined by the Contracting Officer, shall be measured in cubic meters yards. The volume of material in-place and accepted shall be determined by the average job thickness obtained in accordance with paragraph THICKNESS CONTROL and the dimensions shown.

The tonnage of [ABC] [and] [GCA] material shall be the number of metric tons tons of aggregate, [placed and accepted in the completed course] [plus the amount] [placed in authorized stockpiles], as determined by the Contracting Officer. Deductions shall be made for any material wasted, unused, rejected, or used for convenience of the Contractor, and for water exceeding specified amount at time of weighing.

Quantities of [ABC] [and] [GCA], determined as specified above, shall be paid for at the respective contract unit prices, which shall constitute full compensation for the construction and completion of the [ABC] [and] [GCA].

Stabilization of cohesionless subgrade or subbase courses, as specified in paragraph PREPARATION OF UNDERLYING COURSE, shall be paid for as a special item on a tonnage basis. This tonnage price shall include the price of extra manipulation as required.

Government approval is required for submittals with a "G" designation; submittals not having a "G" designation are for [Contractor Quality Control approval.] [information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government.] The following shall be submitted in accordance with Section 01330 01330 01330 SUBMITTAL PROCEDURES:

Sampling and testing shall be the responsibility of the Contractor. Sampling and testing shall be performed by a testing laboratory approved in accordance with Section 01451A 01451A 01451A ContractorR QUALITY CONTROL. Work requiring testing will not be permitted until the testing laboratory has been inspected and approved. The materials shall be tested to establish compliance with the specified requirements; testing shall be performed at the specified frequency. The Contracting Officer may specify the time and location of the tests. Copies of test results shall be furnished to the Contracting Officer within 24 hours of completion of the tests.

Samples for laboratory testing shall be taken in conformance with ASTM D 75. When deemed necessary, the sampling will be observed by the Contracting Officer.

The following tests shall be performed in conformance with the applicable standards listed.

Sieve analysis shall be made in conformance with ASTM C 117 and ASTM C 136. Sieves shall conform to ASTM E 11 . [Particle-size analysis of the soils shall also be completed in conformance with ASTM D 422].

Liquid limit and plasticity index shall be determined in accordance with ASTM D 4318.

The laboratory maximum dry density and optimum moisture content shall be determined in accordance with [ASTM D 1557 ] [AASHTO T 180, Method D and corrected with AASHTO T 224].

Density shall be field measured in accordance with ASTM D 1556, ASTM D 2167 or ASTM D 2922. [For the method presented in ASTM D 1556 the base plate as shown in the drawing shall be used.] [For the method presented in ASTM D 2922 the calibration curves shall be checked and adjusted if necessary using only the sand cone method as described in paragraph Calibration, of the ASTM publication. Tests performed in accordance with ASTM D 2922 result in a wet unit weight of soil and when using this method, ASTM D 3017 shall be used to determine the moisture content of the soil. The calibration curves furnished with the moisture gauges shall also be checked along with density calibration checks as described in ASTM D 3017. The calibration checks of both the density and moisture gauges shall be made by the prepared containers of material method, as described in paragraph Calibration of ASTM D 2922, on each different type of material being tested at the beginning of a job and at intervals as directed.]

Wear tests shall be made on [ABC] [and] [GCA] course material in conformance with ASTM C 131.

Soundness tests shall be made on GCA in accordance with ASTM C 88.

Weight per cubic meter foot of slag shall be determined in accordance with ASTM C 29/C 29M on the [ABC] [and] [GCA] course material.

One of each of the following tests shall be performed on the proposed material prior to commencing construction to demonstrate that the proposed material meets all specified requirements when furnished. If materials from more than one source are going to be utilized, this testing shall be completed for each source.

Each of the following tests shall be performed on samples taken from the placed and compacted [ABC] [and] [GCA]. Samples shall be taken and tested at the rates indicated. [Sampling and testing of recycled concrete aggregate shall be performed at twice the specified frequency until the material uniformity is established.]

The source of the material shall be selected [30] [_____] days prior to the time the material will be required in the work. Tentative approval of material will be based on initial test results. Final approval of the materials will be based on sieve analysis, liquid limit, and plasticity index tests performed on samples taken from the completed and fully compacted course(s).

Construction shall be done when the atmospheric temperature is above 2 degrees C 35 degrees F. When the temperature falls below 2 degrees C 35 degrees F, the Contractor shall protect all completed areas by approved methods against detrimental effects of freezing. Completed areas damaged by freezing, rainfall, or other weather conditions shall be corrected to meet specified requirements.

All plant, equipment, and tools used in the performance of the work shall be subject to approval before the work is started and shall be maintained in satisfactory working condition at all times. The equipment shall be adequate and shall have the capability of producing the required compaction, meeting grade controls, thickness control, and smoothness requirements as set forth herein.

Before the final statement is allowed, the Contractor shall file certified waybills and certified delivery tickets for all aggregates actually used, as specified in the Submittals paragraph.

The [ABC] [and] [GCA] shall consist of clean, sound, durable particles of crushed stone, crushed slag, crushed gravel, [crushed recycled concrete,] angular sand, or other approved material. [ABC shall be free of lumps of clay, organic matter, and other objectionable materials or coatings.] [GCA shall be free of silt and clay as defined by ASTM D 2487, organic matter, and other objectionable materials or coatings.] The portion retained on the 4.75 mm No. 4 sieve shall be known as coarse aggregate; that portion passing the 4.75 mm No. 4 sieve shall be known as fine aggregate.

Coarse aggregates shall be angular particles of uniform density. When the coarse aggregate is supplied from more than one source, aggregate from each source shall meet the specified requirements and shall be stockpiled separately.

ABC coarse aggregate shall not show more than 50 percent loss when subjected to the Los Angeles abrasion test in accordance with ASTM C 131. The amount of flat and elongated particles shall not exceed 30 percent. A flat particle is one having a ratio of width to thickness greater than 3; an elongated particle is one having a ratio of length to width greater than 3. In the portion retained on each sieve specified, the crushed aggregates shall contain at least 50 percent by weight of crushed pieces having two or more freshly fractured faces with the area of each face being at least equal to 75 percent of the smallest midsectional area of the piece. When two fractures are contiguous, the angle between planes of the fractures must be at least 30 degrees in order to count as two fractured faces. Crushed gravel shall be manufactured from gravel particles 50 percent of which, by weight, are retained on the maximum size sieve listed in TABLE 1.

GCA coarse aggregate shall not show more than [40] [50] percent loss when subjected to the Los Angeles abrasion test in accordance with ASTM C 131. GCA coarse aggregate shall not exhibit a loss greater than 18 percent weighted average, at five cycles, when tested for soundness in magnesium sulfate, or 12 percent weighted average, at five cycles, when tested in sodium sulfate in accordance with ASTM C 88. The amount of flat and elongated particles shall not exceed 20 percent for the fraction retained on the 12.5 mm 1/2 inch sieve nor 20 percent for the fraction passing the 12.5 mm 1/2 inch sieve. A flat particle is one having a ratio of width to thickness greater than 3; an elongated particle is one having a ratio of length to width greater than 3. In the portion retained on each sieve specified, the crushed aggregate shall contain at least 90 percent by weight of crushed pieces having two or more freshly fractured faces with the area of each face being at least equal to 75 percent of the smallest midsectional area of the piece. When two fractures are contiguous, the angle between planes of the fractures must be at least 30 degrees in order to count as two fractured faces. Crushed gravel shall be manufactured from gravel particles 90 percent of which by weight are retained on the maximum size sieve listed in TABLE 1.

Fine aggregates shall be angular particles of uniform density. When the fine aggregate is supplied from more than one source, aggregate from each source shall meet the specified requirements.

ABC fine aggregate shall consist of screenings, angular sand, crushed recycled concrete fines, or other finely divided mineral matter processed or naturally combined with the coarse aggregate.

GCA fine aggregate shall consist of angular particles produced by crushing stone, slag, [recycled concrete,] or gravel that meets the requirements for wear and soundness specified for GCA coarse aggregate. [Fine aggregate shall be produced by crushing only particles larger than 4.75 mm No. 4 sieve in size. The fine aggregate shall contain at least 90 percent by weight of particles having two or more freshly fractured faces in the portion passing the 4.75 mm No. 4 sieve and retained on the 2 mm No. 10 sieve, and in the portion passing the 2 mm No. 10 sieve and retained on the 0.425 mm No. 40 sieve.] [Fine aggregate shall be manufactured from gravel particles 95 percent of which by weight are retained on the 12.5 mm 1/2 inch sieve.]

The specified gradation requirements shall apply to the completed base course. The aggregates shall be continuously well graded within the limits specified in TABLE 1. Sieves shall conform to ASTM E 11.

TABLE 1.  GRADATION OF AGGREGATESPercentage by Weight Passing Square-Mesh Sieve
        Sieve
        Designation         No. 1          No. 2           No. 3
        --------------------------------------------------------
        50.0 mm               100           ----            ----
        37.5 mm            70-100            100            ----
        25.0 mm             45-80         60-100             100
        12.5 mm             30-60          30-65           40-70
        4.75 mm             20-50          20-50           20-50
        2.00 mm             15-40          15-40           15-40
        0.425 mm             5-25           5-25            5-25
        0.075 mm              0-8            0-8             0-8

TABLE I.  GRADATION OF AGGREGATESPercentage by Weight Passing Square-Mesh Sieve
         Sieve
         Designation        No. 1          No. 2           No. 3
         -------------------------------------------------------
        2 inch                100           ----            ----
        1-1/2 inch         70-100            100            ----
        1 inch              45-80         60-100             100
        1/2 inch            30-60          30-65           40-70
        No. 4               20-50          20-50           20-50
        No. 10              15-40          15-40           15-40
        No. 40               5-25           5-25            5-25
        No. 200               0-8            0-8             0-8

NOTE 1: Particles having diameters less than 0.02 mm shall not be in excess of 3 percent by weight of the total sample tested.

NOTE 2: The values are based on aggregates of uniform specific gravity. If materials from different sources are used for the coarse and fine aggregates, they shall be tested in accordance with ASTM C 127 and ASTM C 128 to determine their specific gravities. If the specific gravities vary by more than 10 percent, the percentages passing the various sieves shall be corrected as directed by the Contracting Officer.

Liquid limit and plasticity index requirements shall apply to the completed course and shall also apply to any component that is blended to meet the required gradation. The portion of any component or of the completed course passing the 0.425 mm No. 40 sieve shall be either nonplastic or have a liquid limit not greater than 25 and a plasticity index not greater than 5.

When the [ABC] [or] [GCA] is constructed in more than one layer, the previously constructed layer shall be cleaned of loose and foreign matter by sweeping with power sweepers or power brooms, except that hand brooms may be used in areas where power cleaning is not practicable. Adequate drainage shall be provided during the entire period of construction to prevent water from collecting or standing on the working area. Line and grade stakes shall be provided as necessary for control. Grade stakes shall be in lines parallel to the centerline of the area under construction and suitably spaced for string lining.

Clearing, stripping, and excavating shall be the responsibility of the Contractor. The aggregate sources shall be operated to produce the quantity and quality of materials meeting these specifications requirements in the specified time limit. [Upon completion of the work, the aggregate sources on Government property shall be conditioned to drain readily and shall be left in a satisfactory condition.] Aggregate sources on private lands shall be conditioned in agreement with local laws or authorities.

Prior to stockpiling of material, storage sites shall be cleared and leveled by the Contractor. All materials, including approved material available from excavation and grading, shall be stockpiled in the manner and at the locations designated. Aggregates shall be stockpiled on the cleared and leveled areas designated by the Contracting Officer to prevent segregation. Materials obtained from different sources shall be stockpiled separately.

Prior to constructing the base course(s), the underlying course or subgrade shall be cleaned of all foreign substances. At the time of construction of the base course(s), the underlying course shall contain no frozen material. The surface of the underlying course or subgrade shall meet specified compaction and surface tolerances. The underlying course shall conform to [Section 02300 02300 02300 EARTHWORK] [Section 02705 02705 02705 SUBBASE COURSES]. Ruts or soft yielding spots in the underlying courses, areas having inadequate compaction, and deviations of the surface from the requirements set forth herein shall be corrected by loosening and removing soft or unsatisfactory material and by adding approved material, reshaping to line and grade, and recompacting to specified density requirements. For cohesionless underlying courses containing sands or gravels, as defined in ASTM D 2487, the surface shall be stabilized prior to placement of the base course(s). Stabilization shall be accomplished by mixing [ABC] [or] [GCA] into the underlying course and compacting by approved methods. The stabilized material shall be considered as part of the underlying course and shall meet all requirements of the underlying course. The finished underlying course shall not be disturbed by traffic or other operations and shall be maintained by the Contractor in a satisfactory condition until the base course is placed.

The coarse and fine aggregates shall be mixed in a stationary plant, or in a traveling plant or bucket loader on an approved paved working area. The Contractor shall make adjustments in mixing procedures or in equipment as directed to obtain true grades, to minimize segregation or degradation, to obtain the required water content, and to insure a satisfactory base course meeting all requirements of this specification. Adjustments to the JMF shall be limited to plus or minus 5 percent on the 37 mm 1-1/2 inch and coarser sieves; plus or minus 8 percent on the 25 mm 1 inch to 4.75 mm No. 4 sieves; plus or minus 5 percent on the 0.60 mm No. 30 sieve, and plus or minus 3 percent on the 0.075 mm No. 200 sieve. Tolerances given above may permit the aggregate grading to be outside the limits shown in Table 2; this is acceptable.

The mixed material shall be placed on the prepared subgrade or subbase in layers of uniform thickness with an approved spreader. When a compacted layer 150 mm 6 inches or less in thickness is required, the material shall be placed in a single layer. When a compacted layer in excess of 150 mm 6 inches is required, the material shall be placed in layers of equal thickness. No layer shall be thicker than 150 mm 6 inches or thinner than 75mm 3 inches when compacted. The layers shall be so placed that when compacted they will be true to the grades or levels required with the least possible surface disturbance. Where the base course is placed in more than one layer, the previously constructed layers shall be cleaned of loose and foreign matter by sweeping with power sweepers, power brooms, or hand brooms, as directed. Such adjustments in placing procedures or equipment shall be made as may be directed to obtain true grades, to minimize segregation and degradation, to adjust the water content, and to insure an acceptable base course.

The finished and completed base course shall conform to the lines, grades, and cross sections shown. Underlying material(s) shall be excavated and prepared at sufficient depth for the required base course thickness so that the finished base course and the subsequent surface course will meet the designated grades.

The base course(s) shall be placed so that the completed section will be a minimum of [600] [_____] mm [2] [_____] feet wider, on all sides, than the next layer that will be placed above it. Additionally, approved fill material shall be placed along the outer edges of the base course in sufficient quantities to compact to the thickness of the course being constructed, or to the thickness of each layer in a multiple layer course, allowing in each operation at least a 600 mm 2 foot width of this material to be rolled and compacted simultaneously with rolling and compacting of each layer of base course. If this base course material is to be placed adjacent to another pavement section, then the layers for both of these sections shall be placed and compacted along this edge at the same time.

Each layer of the base course shall be compacted as specified with approved compaction equipment. Water content shall be maintained during the compaction procedure to within plus or minus [2] [_____] percent of the optimum water content determined from laboratory tests as specified in paragraph SAMPLING AND TESTING. Rolling shall begin at the outside edge of the surface and proceed to the center, overlapping on successive trips at least one-half the width of the roller. Alternate trips of the roller shall be slightly different lengths. Speed of the roller shall be such that displacement of the aggregate does not occur. In all places not accessible to the rollers, the mixture shall be compacted with hand-operated power tampers. Compaction shall continue until each layer has a degree of compaction that is at least [100] [_____] percent of laboratory maximum density through the full depth of the layer. The Contractor shall make such adjustments in compacting or finishing procedures as may be directed to obtain true grades, to minimize segregation and degradation, to reduce or increase water content, and to ensure a satisfactory base course. Any materials that are found to be unsatisfactory shall be removed and replaced with satisfactory material or reworked, as directed, to meet the requirements of this specification.

Compacted thickness of the base course shall be as indicated. No individual layer shall be thicker than 150 mm 6 inches nor be thinner than 75 mm 3 inches in compacted thickness. The total compacted thickness of the base course(s) shall be within 13 mm 1/2 inch of the thickness indicated. Where the measured thickness is more than 13 mm 1/2 inch deficient, such areas shall be corrected by scarifying, adding new material of proper gradation, reblading, and recompacting as directed. Where the measured thickness is more than 13 mm 1/2 inch thicker than indicated, the course shall be considered as conforming to the specified thickness requirements. Average job thickness shall be the average of all thickness measurements taken for the job, but shall be within 6 mm 1/4 inch of the thickness indicated. The total thickness of the base course shall be measured at intervals in such a manner as to ensure one measurement for each [500] [_____] square meters yards of base course. Measurements shall be made in 75 mm 3 inch diameter test holes penetrating the base course.

Proof rolling of the areas indicated shall be in addition to the compaction specified and shall consist of the application of [_____] coverages with a heavy pneumatic-tired roller having four or more tires, each loaded to a minimum of 13,600 kg 30,000 pounds and inflated to a minimum of 1034 kPa 125 psi. In areas designated, proof rolling shall be applied to the top of the underlying material on which the base course is laid and to each layer of base course [top of the completed [ABC] [GCA] course]. Water content of the underlying material shall be maintained at optimum or at the percentage directed from start of compaction to completion of proof rolling of that layer. Water content of each layer of the base course shall be maintained at the optimum percentage directed from start of compaction to completion of proof rolling. Any base course materials or any underlying materials that produce unsatisfactory results by proof rolling shall be removed and replaced with satisfactory materials, recompacted and proof rolled to meet these specifications.

The surface of the top layer of base course shall be finished after [final compaction] [and] [proof rolling] by cutting any overbuild to grade and rolling with a steel-wheeled roller. Thin layers of material shall not be added to the top layer of base course to meet grade. If the elevation of the top layer of base course is 13 mm 1/2 inch or more below grade, then the top layer should be scarified to a depth of at least 75 mm 3 inches and new material shall be blended in [and compacted] [, compacted and proof rolled] to bring to grade. Adjustments to rolling and finishing procedures shall be made as directed to minimize segregation and degradation, obtain grades, maintain moisture content, and insure an acceptable base course. Should the surface become rough, corrugated, uneven in texture, or traffic marked prior to completion, the unsatisfactory portion shall be scarified, reworked and recompacted or it shall be replaced as directed.

The surface of the top layer shall show no deviations in excess of 10 mm 3/8 inch when tested with a 3.66 meter 12 foot straightedge. Measurements shall be taken in successive positions parallel to the centerline of the area to be paved. Measurements shall also be taken perpendicular to the centerline at [15] [_____] meter [50] [_____] foot intervals. Deviations exceeding this amount shall be corrected by removing material and replacing with new material, or by reworking existing material and compacting it to meet these specifications.

[Traffic shall not be allowed on the completed base course]. [Completed portions of the base course may be opened to limited traffic, provided there is no marring or distorting of the surface by the traffic. Heavy equipment shall not be permitted except when necessary to construction, and then the area shall be protected against marring or damage to the completed work.]

The base course shall be maintained in a satisfactory condition until the full pavement section is completed and accepted. Maintenance shall include immediate repairs to any defects and shall be repeated as often as necessary to keep the area intact. Any base course that is not paved over prior to the onset of winter, shall be retested to verify that it still complies with the requirements of this specification. Any area of base course that is damaged shall be reworked or replaced as necessary to comply with this specification.

Any unsuitable materials that must be removed shall be disposed of [outside the limits of Government-controlled land] [as directed] [in waste disposal areas indicated]. No additional payments will be made for materials that must be replaced.