Field-book for railroad engineers. Containing formulas for laying out curves, determining frog angles, levelling, calculating earth-work, etc., etc., together with tables of radii, ordinates deflections, long chords, magnetic variation, logarithms, logarithmic and natural sines, tangents, etc., etc (1877)
Henck, John Benjamin, 1816-1903 · New York : D. Appleton · leaf 66
the curve, and draw the radii A 0and C 0 and the line CD parallel to A B. Then in the right triangleCOD we have 0 C^ = CD + OD^ But 0 C = R, CD = a, andOD = AO — AD = R — b. Therefore, R = a-{- {R — 6)» =a^ + R^ — 2 Rb -\- b\ or 2 Rb = a^ -{- b^; 2 b Example. Given a = 204 and b = 24, to find R.… … most start to pass through a given point, we have (§65) 2Rb =fl«-f i^ora = 2Rb — b^; ..a = ^b {2R — b). Example. Given 6 = 24 and 72 = 879, to find a. Here o =-/94 (1758 — 24) = ^ 41616 = 204. 67. Corollary 2. If R and a are given, and b is required, wehave (§65) 2 Rb = a^ + 6^ or 6« — 2Rb = —a}.…
Railroad engineering · Ferrovias
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
