NA-1. FLUXED BERMUDEZ ASPHALT FOR CONSTRUCTION. 



The fluxed native asphalt shall be homogenous, free from water, General, 

 and shall not foam when heated to 175° O. (347° F.). 

 It shall meet the following requirements: Physical and 



1. Specific gravity 25V25° C. (77V77° F.) 1.025 to 1.050 ^^t^/^,*."^^ »'""■ 



2. Flash point not less than 175° C. (347° F.) 



3. Melting point 35° C. (95° F.) to 45° C. (113° F.) 



4. Penetration at 25° C. (77° F.) 100 g., 5 sec 120 to 150 



5. Loss at 163° C. (325° F.), 5 hours not more than 3.0% 



a. Penetration of residue at 25° C. (77° F.), 100 g., 5 sec. 



not less than 60 



6. Total bitumen (soluble in carbon disulphide), 



not less than 95.0% 



&. Inorganic matter insoluble 1.5% to 2.5% 



Tests of the physical and chemical properties of the fluxed Methods of test- 

 native asphalt shall be made in accordance with the following *°8" 

 methods : 



1. Specific gravity, U. S. Department of Agriculture Bulletin 



314, p. 5. 



2. Flash point (open cup), IT. S. Department of Agriculture 



Bulletin 314, p. 17. 



3. Melting point, A. S. T. M. Tentative Standard D 36-16 T. 



Proc. A. S. T. M. 1916, p. 549. 



4. Penetration. A. S. T. M. Standard Test D .5-16. 



5. Volatilization test, U. S. Department of Agriculture Bulle- 



tin 314, p. 19, using 50-gram sample. 



6. Total bitumen, U. S. Department of Agriculture Bulletin 



314, p. 25. 



This specification provides for a material to be used in the 

 construction of bituminous macadam in the northern United 

 States. It is intended to cover satisfactory grades of products 

 prepared by fluxing Bermudez asphalt. 



It should be applied at a temperature of from 275° F., to 350° 

 F., to the upper or wearing course of compacted broken stone 

 at the rate of from li to If gallons per square yard. The ap- 

 plication may be made by ,means of pouring pots or by a pressure 

 distributor so designed that it will not produce ruts during 

 application. The above quantities are based on a wearing course 

 3 inches in thickness before rolling, composed of a product which 

 will at least pass a 3-inch laboratory screen and be retained on a 

 1-inch laboratory screen. The exact range in size should be 

 governed by the kind and quality of rock used. The application 

 should be followed by a sufficient amount of clean small sized 



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