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. 
The refined tar shall be homogeneous and free from water. General. 
It shall meet the following requirements: Physical and 
„ / „ n , „ chemical proper- 
1. Specific gravity 25°/25° C. (77°/77° F.), to ties. 
2. Float test at ° C* ( ° 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° C. (518° F.), not more than 
To 300° C. (572° F.), not more than 
(a) Melting point of residue ° C. ( ° F.), to 
° C. ( ° F.). 
4. Total bitumen (soluble in carbon disulphide), to 
per cent. 
Tests of the physical and chemical properties of the refined t csS eth0d8 * f 
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 : ( & ) 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 specific 
viscosity of the material at the temperature applied. In such 
cases insert as follows: Specific viscosity, ° C. ( ° F.), 
to 
SPECIFICATION FOR REFINED TAR FOR USE AS POURED JOINT FILLER. 
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. 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. 
General. 
Physical and 
chemical proper- 
ties. 
Methods of 
testing. 
SPECIFICATION FOR PORTLAND CEMENT.f 
(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. 
Definition. 
* It is recommended that the float test be 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 1913 Standards of the American 
Society for Testing Materials, p. 429, etc., Serial Designation C9-17. 
88979 s — 17— Bull. 555 4 
