139 SECTION 305 DESCRIPTION
305.01.01 General. This work consists of pulverizing, blending with cement , and compacting an existing
roadway. MATERIALS
305.02.01 General. Material shall conform to the following Sections and Subsections:
Portland Cement ................................ ................................ ................................ ................................ ................................ .... Section 701 Cutback Asphalt ................................ ................................ ................................ ................................ ...................... Subsection 703.03.03 Sand Blotter ................................ ................................ ................................ ................................ ............................ Subsection 705.03.05 Water ................................ ................................ ................................ ................................ ................................ ..................... Section 722 Portland cement may be either Type I, Type IP “blended,” Type II, or Type V. The limitation on the amount of alkali in cements is hereby waived.
305.02.02 Gradation Requirements. Loosen and pulverize the existing roadway to conform to the following
sieve sizes: Sieve Size Percent Passing by Mass 75 mm (3 in.) ................................ ................................ .............. 100 50 mm (2 in.) ................................ ................................ ............ 95-100 CONSTRUCTION
305.03.01 Weather Limitations. Do not process for roadbed modification while the atmospheric temperature is
below 2 °C (35 °F), or when conditions indicate that the temperature will fall below 2 °C (35 °F) for a sustained period of 4 hours within 24 hours after fina l compaction. Do not proceed with the pulverization operation when the temperatures will not permit the processing operation to follow. If atmospheric temperatures fall below 2 °C (35 °F) for a sustained period of 4 hours within 24 hours, the Engineer wi ll determine if the processed material may remain in place. If the material is allowed to remain in place, reprocess with an additional 0.5% cement by mass. Perform such work at no cost to the Department.
305.03.02 Preparation of Roadbed. Pulverize the ex isting roadway to the depth necessary to construct the
roadbed modification as shown on the plans. Roll as directed with pneu matic tired roller and pregrade the pulverized material to within 25 mm (1 in.) of grade. Maintain the pulverized surface in an a cceptable condition, until the processing for roadbed modification begins. Restrict the pulverization operation to half roadway width at a time. Relay the pulverized material by one of the following methods and place public traffic thereon at the end of each working day:
a.Relay and satisfactorily compact the unprocessed pulverized material.
b.Add cement, process, spread, and compact the material, according to the requirements for the finished product. Do not pulverize more than 5 km (3 mi) in advance of the completed roadbed modification process. Distribute only as much Portland cement on the pulverized surface material and base as can be mixed and compacted within the same working day. 305 ROADBED MODIFICATION 140 305.03.03 Proportioning. Add Portland cement to the pulv erized material at the rate of 2% by mass. The calculated maximum density (as determined by Test Method No. Nev. T10 8) of the pulverized material will be used to determine the mass of the material in place. Add the cement in a dry state and take every precaution to prevent blowing. Do not vary the rate of cement spread more than 10% from the designated rate.
305.03.04 Mixin g. Use roadmix machine of a pugmill type, auger type, or cross -shaft type mixer capable of
providing a uniform homogeneous mixture throughout the material to the depth indicated on the plans. Furnish cement in bulk. Distribute cement, by mechanical equipm ent, on the pulverized material in a layer of uniform thickness. Calibrate each load in the spreading equipment so the average rate of spread can be determined. Spread the cement upon the pulverized material at an acceptable distance ahead of the roadmixin g operations. Use a roadmixing machine with provisions for introducing water at the time of mixing, through a metering device or by other approved methods. Apply the water by controls that will supply the correct quantity of water to produce a completed m ixture with uniform moisture content. Leakage of water from equipment will not be permitted. Avoid the addition of any excessive water. The quantity of water added to the mixture will be determined. Do not exceed optimum water content in the complete mixtu re as determined by Test Method No. Nev. T10 8. Mix the components to the depth shown on the plans until a uniform homogeneous mixture is obtained. If equipment is used that requires more than one pass of the mixer, make at least one pass before any water is added to the material.
305.03.05 Compacting and Finishing. After mixing, compact the mixture to no less than 95% relative
maximum density as determined by Test Method No. Nev. T10 8. The in -place density will be determined by Test Methods No. Nev. T102 or T103. Accompany compaction by sufficient blading to shape the surface to the specified longitudinal grade and cross -slope, or as directed. Produce a uniform surface that is free of cracks, ruts, humps, depressions, and loose material. Correct or repair all deficiencies by approved methods. Compact with a two -axle tandem steel roller weighing not less than 9 metric tons (10 tons), or single or dual drum vibratory roller, and pneumatic tired rollers conforming to Subsection 401.03.04. Use roller sequence as directed. Equip motor graders with cross slope and automatic grade controls that are capable of picking up grade from an external sensing wheel.
305.03.06 Surface Tolerances. When a 3.6 m (12 ft) straightedge is laid in any direction, the finished sur face
shall not deviate at any point more than 12 mm (0.04 ft) from the bottom thereof. Correct defective areas by approved methods.
305.03.0 7 Protection and Curing. Keep the surface moist at all times until the curing seal is applied. Use water
equipment of a type which will apply moisture in a fog or mist type application free of pressure at the surface being treated . Apply curing seal to the completed cement treated, pulverized material. Apply the curing seal as soon as possible, but not later than 24 hours after completion of final rolling. Curing seal shall be Cutback Asphalt , Type MC-250 applied at the rate shown on the plans or as directed. At the time of application of the curing seal, the surface shall be tightly knit, free from all loose material and shall contain sufficient moisture to prevent excessive penetration of the asphalt. If necessary, apply water to fill the surface voids immediately before the asphalt is applied. Apply the curing seal according to Section 407. Equipment or traffic ma y be permitted on the cement treated material when approved, after the curing seal has set and sand blotter has been applied as directed. Maintain the cement treated material in an acceptable condition. Remove all loose sand from the cement treated mater ial before any surfacing material is placed thereon. ROADBED MODIFICATION 305 141 METHOD OF MEASUREMENT
305.04.01 Measurement. Pulverizing the existing surface will be measured by the kilometer (mile) along
centerline of the roadbed full width, or by the square meter (square yard). Processing for roadbed modification will be measured by the square meter (square yard) for the mixing of the materials, the compaction of the mixture , and the finishing of the completed base. Portland cement will be measured by the metric ton (ton) as d etermined by the following methods:
a.Certified packaged masses.
b.Certified scale masses.
c.Certified mass certificates indicating the truck and trailer number, tare mass, gross mass, net mass and date. The following requirements shall apply:
1.Loaded transporting vehicles shall be occasionally weighed by project personnel before discharge of any material. The frequency in which the loaded vehicles are weighed will be determined.
2.Every empty transporting vehicle shall be weighed by project p ersonnel before the vehicle leaves the project.
3.The quantity of Portland cement used will be determined, should a discrepancy arise, between project masses of the loaded or unloaded vehicles, or both, and the certified mass certificates. Cutback aspha lt used for curing seal and sand blotter will be measured under Section 407. BASIS OF PAYMENT
305.05.01 Payment. The accepted quantities, measured as provided above, will be paid for at the contract
price per unit of measurement for the pay items listed below that are shown in the proposal. Payment will be full compensation for the work prescribed in this Section. Payment will be made under: Pay Item Pay Unit Portland Cement ................................ ................................ ................................ ................................ ............................. Metric Ton (Ton) Processing for Roadbed Modification ................................ ................................ ................................ ........... Square Meter (Square Yard) Pulverize Existing Surface ................................ ................................ ............................... Kilometer (Mile) or Square Meter (Square Yard) 143 SECTION 307 SHOULDERING MATERIAL DESCRIPTION
307.01.01 General. This work consists of shoulder preparation and placing shouldering material.
MATERIALS
307.02.01 General. Material shall conform to the following Section and Subsection:
Shouldering Material ............................................................................................................................................... Subsection 704.03.09 Water ..................................................................................................................................................................................... Section 722 CONSTRUCTION
307.03.01 Shoulder Preparation. Prior to the placement of shouldering material, clear and grub all shoulders
for a minimum width of 3 m (10 ft) from the edge of pavement, but no more than needed to place and compact the material. Clear and grub to remove all vegetation, organic material, trash, and non-organic material greater in size than the largest allowable gradation specified for the shouldering material, or the largest allowable gradation specified for cold millings when milled material is to be placed. Do not alter or modify existing drainage unless directed. Dispose of the material resulting from the shoulder preparation according to Subsection 107.14, unless otherwise directed.
307.03.02 Placement and Compaction. Initially place the shouldering material by mechanical means.
Windrows exceeding 100 mm (4 in.) in height will not be allowed when the adjacent lane is open to traffic. Place all material within the limits of the prepared shoulder. Do not place material in roadway ditches or on back slopes. Grade the lower edge of the shouldering material flush with the existing slope. Grade and compact shouldering material after paving has been completed. Finish shoulders by grading material according to Subsection 105.03. Achieve final compaction by applying enough water to adequately wet all material and roll with a steel wheeled roller at all locations unless otherwise directed. Place, finish, and compact all shouldering material to the satisfaction of the Engineer. METHOD OF MEASUREMENT
307.04.01 Measurement. Shouldering material will be measured by the metric ton (ton).
The mass of any water added to the shouldering material before weighing will be deducted from the quantity measured for payment. BASIS OF PAYMENT
307.05.01 Payment. The accepted quantities, measured as provided above, will be paid for at the contract unit
price per unit of measurement for the pay item listed below that is shown in the proposal. Payment will be full compensation for the work prescribed in this Section. Payment will be made under: Pay Item Pay Unit Shouldering Material ....................................................................................................................................................... Metric Ton (Ton)
Source: Nevada Standard Specifications for Road and Bridge Construction, 2014 Edition. Pages 145–148 of 610.