DUST PREVENTION AND ROAD PRESERVATION. 



21 



Experiment No. 4. — Residual asphaltic petroleum — Hot application. 



Location: From station 209+00 to station 280+00. 



Length: 7,100 feet. 



Date of application: From October 9 to October 15. 



Temperature of oil: Maximum 210° F., minimum 165° F., average 188° F. 



Table 24. — Analysis of residual asphaltic petroleum l used in experiment No. 4- 



Specific gravity 25 °/25 ° C 1. 002 



Flash point ° C 86 



Burning point ° C 175 



Viscosity, Engler, 100° C. , 50 c. c. specific , 21.0 



Per cent of loss at 163 ° C, 5 hours (20 grams) 9. 23 



Float test of residue (50° C.) (time) 2 2'42" 



Per cent of bitumen insoluble in 86 ° B. naphtha 10. 55 



Per cent of fixed carbon 5. 63 



Per cent soluble in CS 2 (total bitumen) 99. 93 



Per cent of organic matter insoluble 06 



Per cent of inorganic matter insoluble 01 



Total 100. 00 



Details. — From station 241 + 50 to station 251+07 the macadam was 

 first well sprinkled with water and the oil was applied while the road 

 surface was still moist. Owing to the viscosity of the oil and the 

 cool weather, some difficulty was experienced in starting the dis- 

 tributor pump. This resulted in the formation of pools of thick oil 

 at the beginning of each trip before the nozzles worked uniformly 

 enough to have the team start. After a few experiences with this 

 trouble, the distributor nozzles were allowed to discharge into the 

 ditch until a uniform distribution began. 



Experiment No. 5.- — Residual asphaltic petroleum — Hot application. 



Location: From station 280+00 to station 347+75. 



Length: 6,775 feet. 



Date of application: From October 21 to November 21. 



Temperature of oil: Maximum 221° F., minimum 167° F., average 200° F. 



Table 25. — Analysis of residual asphaltic petroleum 1 used in experiment No. 5. 



Car No. 1. 



Car No. 2. 



Specific gravity 25 °/25 ° C 



Viscosity, Engler, 100° O, 50 c. c. specific 



Float test at 50° C. (time) 



Per cent of loss at 163° O, 5 hours (20 grams) 



Float test of residue (50 ° C.) (time) 3 



Per cent of total bitumen insoluble in 86° B. naphtha 

 Per cent of fixed carbon 



Per cent soluble in CS2 (total bitumen) 



Per cent of organic matter insoluble 



Per cent of inorganic matter insoluble 



Total......... 



0.990 

 26.0 

 1'28" 

 3.03 

 2'50" 

 19.29 

 10.47 



99.97 

 .02 

 .01 



100. 00 



0.998 

 37.5 

 1'26" 

 2.63 



2'45" 

 18. 83 

 10.64 



99.90 

 .10 

 .00 



100. 00 



Sticky, viscous fluid. 



2 Sticky, semisolid. 



3 Soft, sticky. 



f. 4 



