Pg 82 - Laserfiche WebLink

Home Browse Search

.an. and, the Tan. curve. ingent: gent. xternal : �rnal. I.: Tan. trve will S.,3 CURVE TABLES 2.4" Sdi &B, CO, /fo` Published by KEUFFEL & ESSER CO. HOW TO USE CURVE TABLES I` y �I Table I. contains Tangents and Externals to a 1° curve. i Ext. to any other radius maybe found nearly enough, by dividing or Ext. opposite the given Central Angle by the given degree o; To find Deg. of Curve, having the Central Angle and T, Divide Tan. opposite the given Central Angle by the given Tan To find Deg. of Curve, having the Central Angle and E Divide Ext.opposite the given Central Angle by the given Ext To find Nat. Tan. and Nat. Ex. Sec. for any angle by Table or Ext. of twice the given angle divided by the radius of a 1° ct be the Nat. Tan. or Nat. Ex. Sec. EXAMPLE tt Wanted a Curve with an Ext. of about. 12 ft. Angle of Intersection or I. P. =230 20' to the R. at Station 542+72. Ext. in Tab. I opposite 23° 20' =120.87 1.20.87+12=10.07. Say a 10° Curve. Tan. in Tab. I opp. 23° 20'= 1183.1 E, ft ;, I 1183.1=10=118.31. Correction for A. 23° 20' for a 10° Cur. =0.16 118.31 +0.16 = 118.47 = corrected Tangent. (If corrected Ext. is required find in same way) Ang.23°20'=23.33°=10=2.3333=L. C. l r' t� ' 2° M,'= def. for sta. 542 I. P. = sta. 542-72 o ,i_ u a ° 4 492"= +50 Tan. = 1 .18.41 G a k o '=543 j 9° 49}'= ° ° ° +50 B. C.=sta. 541+53.5:: 110 40' _ a a ,543+ L. C. = 2 .33.31 86.86 E. C.=Sta. 543+86.86 100-53.53=46.47X3'(def. for 1 ft. of 10° Cur.)=139.41'= 2° 19"=def. for sta. 542. Def. for 50 ft. =2° 30' for a 10° Curve. Def. for 36.86 ft. =1° 501' for a 10° Curve. . Pia x) _ d I.P.An9.23.201 7 B i 10• Gurve t y 0X4 , \\V / i .an. and, the Tan. curve. ingent: gent. xternal : �rnal. I.: Tan. trve will