Patent GB-191513753-A (GB)
Title: Paving Composition and Method of Producing the same.
Inventor: STABER ERNEST HENRY
IPC: E01C7/18
Filed: 1915-09-27
Abstract: 13,753. Staber, E. H. Sept. 27. Compositions containing bituminous and siliceous and like materials.-A composition for paving consists of bituminous matter, a mineral aggregate of different sizes to give a maximum density as shown by Fig. I., and impalpable powder in accordance with Fig. II. to comply with any given temperature conditions as to softening point. Fig. I shows seven maxi. mum density curves for mineral aggregates. Curve A; for example, gives the grading required to 'produce a mixture of maximum density, that is one in which the voids are reduced to a minimum when the largest piece of mineral aggregate is of such a size that it will just pass through a 3 in. sieve. The ordinates represent the sizes of the sieves, and the abscissµ the percentages passing through the sieves, the numbers at the top of the Figure giving the percentages retained on the sieves. Thus, curve A shows that 100 per cent passes the 3 in. sieve, 12À2 per cent is retained on the 2¢ in. sieve, 12À2 on the 2 in., 11À6 on the 1¢ in., and so on. Fig. 11. shows the effect of various percentages of 200-mesh powder (impalpable powder) upon the softening-point of asphalt. The following particular compositions are claimed: (1) a composition of 6 in. or more in thickness containing 79 per cent of mineral aggregate passing a 3 in. sieve but retained on successive sieves down to a # in. sieve, 18 per cent of mineral aggregate passing a # in. sieve but retained on successive sieves down to a 200-mesh sieve, 3 per cent or less of impalpable powder passing a 200-mesh sieve, and an additional 4 per cent or more of bitumen; (2) a composition of from 2-6 ins. thick containing 59 per cent of mineral aggregate passing a 1 in. sieve but retained on successive sieves down to a # in. sieve, 31 per cent of mineral aggregate passing a # in. sieve Lut retained on successive sieves down to a 200-mesh sieve, 10 per cent or less of impalpable powder passing a 200-mesh sieve, and an.additional 4 per rent or more of bitumen; (3) a composition of 1-2 ins. thick containing 40 per cent of mineral aggregate passing a ¢ in. sieve but retained on successive sieves down to a # in. sieve, 42 per cent of mineral aggregate passing a # in. sieve but retained on successive sieves down to a 200-mesh sieve, 18 per cent or less of impalpable powder passing a 200-mesh sieve, and an additional 4 per cent or more of bitumen; and (4) a composition of “-1 in. thick containing 74 per cent of mineral aggregate passing a # in. sieve but retained on successive sieves down to a 200-mesh sieve, 26 per cent or less of impalpable powder, and an additional 4 per cent or more of bitumen. The bitumen and impalpable powder are to a certain extent interchangeable, and the powder may be increased above the proportions given. The phrase "retained on successive sieves" indicates that, in the proportions given, all the sieves of any series must be used, and the proportions of the material retained by each sieve are in accordance with those shown on the curves given in Fig. I.