. American engineer and railroad journal . hand is different from one for the left hand. While the problems connected with three-rail turnoutsare quite simple, and readily calculated by the use of planetrigonometry, they are commonly confusing from the largenumber of cases that present themselves. It is the purpose in this paper to discuss the manner ofthe ready solution of such problems as are likely to bepresented to the engineer. To this end formulas for suchcases are deduced, and, to further simplify the matter,numerous numerical examples are given. From the formu-las and numerical example
. American engineer and railroad journal . hand is different from one for the left hand. While the problems connected with three-rail turnoutsare quite simple, and readily calculated by the use of planetrigonometry, they are commonly confusing from the largenumber of cases that present themselves. It is the purpose in this paper to discuss the manner ofthe ready solution of such problems as are likely to bepresented to the engineer. To this end formulas for suchcases are deduced, and, to further simplify the matter,numerous numerical examples are given. From the formu-las and numerical examples thus given, it is believed thatthe engineer may, without difficulty, find just what he may Letting Z) equal the chord deflection, or twice the throw,C, the length of chord required, and R, the radius, Henck (Prob. l8j shows that d = —, whence we have ; Example : Let the throw be 5 in. and the radius chord length of the throw rail. Twice the throw = 10 in. = o 833 ft. i: = Extracting sq. rootC = 25 ft. 2i in. = want, and readily apply the proper formulas to any particu-lar case. It may be noted that while the formulas are primarilyprepared for the solution of three-rail turnouts, many ofthem are equally applicable to all the cases that arelikely to occur for ordinary turnouts, not only from tan-gents but from curves as well. In the following discussion the turn-out curve will be regarded as a cir-cular curve, that representing the outerrail H B, hg. i. being tangent to theline FH nnd F B. these tangents be-ing of equal length where H repre-sents the heel of the switch and B thepoint of the frog. This method of regarding the turn-outs will be found to agree as closelywith actual practice as other methodsin vogue, and, besides, has the meritof simplicity. In this connection, it may be re-marked, that for ordinary , in his Turnouts, regardsthe turnout curve as circular. In the case of three-rail turnouts,we commonly have the gauges, thea
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroadengineering
