FORMS FOR SPECIFICATIONS, ETC., FOR ROAD MATERIALS. 



25 



SPECIFICATION FOR REFINED TARS FOR USE IN BITUMINOUS MACADAM AND 

 BITUMINOUS CONCRETE, OR AS SEAL COAT OR FOR HOT APPLICATION. 



General. 



Physical and 

 chemical proper- 

 ties. 



Methods ef 

 testing. 



The refined tar shall be homogeneous and free from water. 

 It shall meet the following requirements : 



1. Specific gravity 25°/25° C. (77°/77° F.), to 



2. Float test at ° 0.* ( ° F.), to sec. 



3. Total distillate by weight : 



Per cent. 



To 170° C. (338° F.), not more" than 



To 235° C. (455° F.), not more than 



To 270° 0. (518° F.), not more than 



To 300° C. (572° F.), not more than 



(a) Melting point of residue ° O. ( ° F.), to 



° 0. ( ° F.). 



4. Total bitumen (soluble in carbon disulphide), to 



per cent. 



Tests of the physical and chemical properties of the refined 

 tar shall be made in accordance with the methods described, or 

 referred to, on page of these specifications, tests Nos. 



Notes. — (1) In some instances it may be desirable to insert a 

 specific gravity of distillate requirement after the melting point 

 requirement, in which case the wording should be : ( b ) Specific 

 gravity of total distillate, 25°/25° C.) (77°/77° F.), to 



(2) In some instances it may be considered desirable to insert 

 a requirement for solubility in dimethyl sulphate of one or more 

 fractions of the distillate. In such cases insert as follows: Solu- 

 bility in dimethyl sulphate of distillate, from ° C. ( ° 



F.) to ° C. ( ° F.), to per cent. 



(3) In some instances it may be desirable to specify the spec' fie 

 viscosity of the material at the temperature applied. In such 



cases insert as follows: Specific viscosity, c C. ( ° F.), 



to 



SPECIFICATION FOR REFINED TAR FOR USE AS POURED JOINT FILLER. 



The refined tar shall be homogeneous and free from water. General. 



It shall meet the following requirements : 



1. Specific gravity, 25°/25° C. (77°/77° F.), to 



2. Melting point, ° C. ( ° F.) to ° C. ( ° F.). 



3. Total bitumen (soluble in carbon disulphide), to 



per cent. 



Tests of the physical and chemical properties of the refined tar 

 shall be made in accordance with the methods described or re- 

 ferred to on page of these specifications, tests Nos. 



SPECIFICATION FOR PORTLAND CEMENT, t 



(1) Portland cement is the product obtained by finely pulveriz- 

 ing clinker produced by calcining to incipient fusion an intimate 

 and properly proportioned mixture of argillaceous and calcareous 

 materials, with no additions subsequent to calcination except 

 water and calcined or uncalcined gypsum. 



* It is recommended that the float test he made at 32° C. (89.6° F.) 

 or 50° C. (122° F.), according to the nature of the product desired. 



t Conforming with the report of a joint conference representing the 

 United States Government, American Society of Civil Engineers, and the 

 American Society for Testing Materials, published in Bureau of Standards 

 Circular No. 33, 3d edition, and in the 1918 Standards of the American 

 Society for Testing Materials, p. 429, etc., Serial Designation C9-17. 



88979°— 17— Bull. 555 4 



Physical and 

 chemical proper- 

 ties. 



Methods of 

 testing. 



Definition. 



