- 353 - SECTION 512 -- BITUMINOUS SURFACE COURSE
512.01 Description
1.This work will consist of cons tructing a surface course composed of milled or pulverized bituminous material obtained from sources shown in the contract. The bituminous material shall be distributed and spread as shown in the contract.
512.02 Material Requirements
1.The bituminous material shall be pulverized until all of the material will pass a 2 inch (50 mm) sieve.
512.03 Construction Methods
1.The Contractor shall obtain and place the bituminous materials as shown in the contract.
2.Before placing the material, the area on which this material is to be placed shall be smoothed and any vegetat ion removed by the Contractor.
3.The surface shall be adjusted to accommodate the thickness of the bituminous surface course.
4.The Contractor shall compact the bituminous material with three complete coverages of a roller or other approved compaction equipment.
512.04 Method of Measurement
1.The bituminous surface course will be measured for payment by the square yard (square meter).
512.05 Basis of Payment
1.P a y I t e m P a y U n i t Bituminous Surface Course Square Yard (SY) [Square Meter (m 2)]
2.Payment is full compensation for all work described in this Section. - 354 - SECTION 513 -- FOG SEAL
513.01 Description
1.The fog seal shall be a light applic ation to an existing surface of an emulsified asphalt diluted with water. The emulsified asphalt shall be similar to a tack coat, and applied at the required application rate. The application locations will be as shown in the contract.
513.02 Material Requirements
1.The fog seal shall be of the ty pe and grade shown in the contract, and the emulsified asphalt shall confo rm to the requirements of Sections 1031 or 1032. Fast-Set type emulsified asphalt shall meet the requirements of Section 504, Table 504.01.
2.The Contractor shall dilute the emulsified asphalt at a rate of maximum one part water to one part emulsified asphalt. The percent residue by distillation of the diluted emulsifi ed asphalt shall be no less than 28.5%.
a.If the dilution is performed in the field, and the rate can be verified, a sample for verification of proper dilution is not required. A sample of the undiluted material may be requested by the Department.
b.If the dilution is performed in the field, and the rate cannot be verified, a sample for verification of proper dilution of each truckload is required.
c.If the emulsified asphalt was diluted at the supplier terminal, the Department Laboratory may request a sample for proper dilution verification. The bill of lading or deliver y ticket shall state the dilution rate.
513.03 Construction Methods
1.Before the application of the f og seal, the Contractor shall clean the surfaces as described in Section 501.
2.a. The application of asphaltic materials shall be allowed only when:
1.The ambient air temperature is above 60°F (16 C).
2.The surface is dry. The Engineer may allow the application of emulsified asphalt to a damp surface if all standing water has been removed from the surface and no fu rther precipitation is expected.
b.The Contractor shall demons trate the ability to distribute a uniform coat of asphaltic material bef ore beginning work. A coat of the specified emulsified asphalt shall be ap plied to a test strip of tar paper or other suitable material. The strip sha ll be 10 feet (3 m) long and as wide as the spray bar. If the Engineer determines the application to be unsatisfactory, the Contract or shall adjust the equipment and repeat the test procedure until satisfactory results are obtained. The Contractor shall properly dispose of the test strip after use.
c.The emulsified asphalt shall be diluted in the distributor or transport with potable water as shown in the contract. The rate of application shall be 0.12 Gal/SY. The di stributor shall be shut off before the tank is entirely empty.
d.Hand sprayers shall be used in applying asphaltic materials to small or irregular sections.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 387–387 of 1,048.