34 



BULLETI]Sr 407, XJ. S. DEPARTMENT OF AGEICULTURE. 



Table 35. — Analysis of bituminous concrete {Topeha specification). 



Per cent. 



Bitumen soluble m CSg 8. 25 



Iilineral aggregate: 



Passing ^-inch screen, retained on J-inch screen 7. 9 



Passing |-incli screen, retained on lO-mesh sieve 17. 2 



Passing lO-mesh sieve, retained on 20-mesh. sieve 17. 3 



Passing 20-mesh sieve, retained on 30-mesli sieve 9. 8 



sLng 30-mesli sieve, retained on 40-mesli sieve 9. 3 



40-mesli sieve, retained on 50-mesh sieve 10. 2 



Passing 50-mesh sieve, retained on 80-mesh sieve 14. 2 



Passing 80-mesh sieve, retained on 100-mesh sieve 2. 7 



Passing 100-mesh sieve, retained on 200-me8h sieve 7. 5 



Passing 200-mesh sieve 3. 9 



Total 100. 



Table 36. — Analysis of bituminous concrete {District of Columbia specification). 



Per cent. 



Bitumen soluble in CSg 7. 2 



Mineral aggregate: 



Passing 1-inch screen, retained on f-inch screen 6. 8 



Passing f-inch screen , retained on J-inch screen 14. 4 



Passing ^-inch screen, retained on J-inch screen 24. 3 



Passing J-inch screen, retained on 10-mesh sieve 14. 



Passing 10-mesh sieve, retained on 20-mesh sieve 7. 5 



Passing 20-mesh sieve, retained on 30-mesh sieve 6. 1 



Passing 30-mesh sieve, retained on 40-mesh sieve 6. 4 



Passing 40-mesh sieve, retained on 50-mesh sieve 6. 2 



Passing 50-mesh sieve, retained on 80-mesh sieve 4. 4 



Passing 80-mesh sieve, retained on 100-mesh sieve 1. 1 



Passing 100-mesh sieve, retained on 200-mesh sieve 4. 4 



Passing 200-mesh sieve 4. 4 



Total 100. 



Table 37. — Analyses of oil asphalts used in experiments at Washington, D. C. 



Use. 



Bituminous 

 concrete 



Seal 

 coat. 



Specific gravity 25°/25° C 



Melting point, " C 



Penetration at 25° C, 100 grams, 5 seconds 



Loss, 5 hours at 163° C, 20 grams, per cent 



Penetration of residue, as above 



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

 Fixed carbon, per cent 



Soluble in CS2 (total bitumen), per cent 



Organic matter insoluble, per cent 



Inorganic matter insoluble, per cent 



Total, per cent 



055 



40 



26.40 



19.32 



98.39 

 .70 

 .91 



1.055 

 58.5 

 47 



.31 

 34 



31.76 

 19.33 



100.00 



