76 DEPARTMENT BULLETIN 1216, U. S. DEPT. OF AGRICULTURE 
residues, which shall be mixed and poured at a temperature of 100° to 125° C. 
It shall be stirred thoroughly until it is homogeneous and free from air bubbles. 
The sample shall then be poured into the collar in any convenient manner until 
slightly more than level with the top. 
Asphalt and asphalt products. — Asphalt and asphalt products shall be cooled 
to room temperature, placed in water maintained at 5° C. for five minutes, 
after which the surplus material shall be removed by means of a spatula, or 
steel knife, which has been slightly heated. The collar and plate shall then 
be placed in a tin cup containing ice water maintained at 5° C, ± 1° C, and 
left in this bath for at least 15 minutes. 
Tar products. — Tar products shall be immediatey immersed in ice water 
maintained at 5° C. for five minutes, after which the surplus material shall be 
removed by means of a spatula or steel knife, which has been slightly heated. 
The collar and plate shall then be placed in a tin cup containing ice water 
maintained at 5° C, ± 1° C, and left in this bath for at least 15 minutes. 
PROCEDURE 
7. (a) The bath shall be filled with water and the water heated to the tem- 
perature at which the test is to be made. This temperature shall be accurately 
maintained and shall at no time throughout the test be allowed to vary more 
than 0.5° C. from the temperature specified. 
(b) After the material to be tested has been kept in the ice water for not 
less than 15 minutes nor more than 30 minutes, the collar with its contents 
shall be removed from the plate and screwed into the aluminum float and 
immersed in water at 5° C. for one minute. Any water shall then be removed 
from the inside of the float and the latter immediately floated in the warm 
bath. As the plug of material becomes warm and fluid, it is forced upward 
and out of the collar until the water gains entrance into the saucer and causes 
it to sink. 
(c) The time in seconds between placing the apparatus on the water and 
when the water breaks through the material shall be determined by means of 
a stop watch, and shall be taken as a measure of the consistency of the material 
under examination. 
Note. — Special precaution should be taken to insure the collar fitting tightly into the 
float and to see that there is no seepage of water between the collar and float during 
the test. 
51. METHOD OF TEST FOR DUCTILITY OF BITUMINOUS 
MATERIALS 
(A. S. T. M. tentative standard method (5), serial designation D 113-26 T) 
1. The ductility of an asphalt cement or semisolid bitumen is measured by 
the distance to which it will elongate before breaking when two ends of a 
briquet of the material are pulled apart at a specified rate of speed and at a 
specified temperature, which for a normal test shall be 5 centimeters per minute 
at 25° C. (77° F.). 
APPARATUS 
2. The mold shall be as shown in Figure 29. It shall be made of brass, 
the ends, b and b', being known as clips, and the parts, a and or', as sides of 
the mold. The dimensions of the mold shall be as follows : 
Centimeters 
Total length (internal) 7.45 to 7.55 
Distance between clips 2. 97 to 3. 06 
Width of clips at mouth 1.98 to 2.02 
Width of briquet at minimum cross section (halfway between 
clips) 1 0.99 to 1.01 
Thickness of briquet throughout 0.99 to 1.01 
3. The water bath shall be maintained at a temperature not varying more 
than 0.1° C. from 25° C. (77° F.). The volume of water shall be not less than 
10 liters and the sample shall be immersed to a depth of not less than 10 centi- 
meters and shall be supported on a perforated shelf not less than 5 centimeters 
from the bottom of the bath. 
4. Any apparatus may be used for pulling the briquet of bitumen apart that 
is so constructed that the briquet will be continuously immersed in water and 
