. A manual of the principles and practice of road-making: comprising the location, consruction, and improvement of roads (common, macadam, paved, plank, etc.) and rail-roads . station 5, 820 + 65 = 885 feet. Adopting these new distances, and changing the cuttings andfillings in accordance with the elevations of grade obtained bythe proportions on the preceding page, they will stand thus : Station. Distance. Elevationof grade. New Cut. New Fill. 1 0 2 561 3 858 4 760 0 0 5 885 6 825 7 330 The calculations being repeated with these data, it wil
. A manual of the principles and practice of road-making: comprising the location, consruction, and improvement of roads (common, macadam, paved, plank, etc.) and rail-roads . station 5, 820 + 65 = 885 feet. Adopting these new distances, and changing the cuttings andfillings in accordance with the elevations of grade obtained bythe proportions on the preceding page, they will stand thus : Station. Distance. Elevationof grade. New Cut. New Fill. 1 0 2 561 3 858 4 760 0 0 5 885 6 825 7 330 The calculations being repeated with these data, it will befound that the excavation will amount to 2,048,000 cubic feet, 122 THE LOCATION OF ROADS. and the embankment to 1,980,000 ; an apparent surplus of68,000 cubic feet; but since, in order to allow for the shrink-age, there should be an excess of 205,000, it appears that thereis really a Wantage, and that the grade has been raised toomuch ; so that an elevation of only 2|- feet at B would probablyproduce the desired balance. TRANSVERSE BALANCING. When the road lies along the side of a slope, so that itis partly in excavation and partly in embankment, it is xie Fig. 58. cessary so to place its centre line, that these two parts ofits cross-section may balance. When the ground has auniform slope, the desired end would be obtained (if theside slopes were the same for excavation and embank-ment, and if no shrinkage existed) by locating the cen-tre line of the road on the surface of the ground. In othercases, as when the side of the excavation slopes 1 to 1,and that of the embankment 2 to 1, a formula to determinethe position of the centre Hne of the road may be readilyestablished. If earlh be wanted for a neighboring embankment, theamount of excavation may be easily increased by movingthe road farther into the hill, with the additional advantageof lessening its liability to slip. The line may be thus TRANSVERSE BALANCING. 123 changed on the map, according to the notes of cross-secti
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectrailroa, bookyear1853
