Curve & Setting Out Of Circular Curve
Curve, Horizontal curves are generally of three types, Simple Circular Curve, Compound Curve, Reverse Curve, Broken-back Curve, Basic Definitions- Back tangent, Forward tangent, Vertex or point of intersection, Deflection angle, Point of Curvature (P.C.), Point of tangency(P.T.), Tangent distance (T), External distance (E), Long chord (L), Mid ordinate (M), Length of curve (l), Elements of Circular Curve- Length of Tangent (T), Length of Curve (l), Mid Ordinate (M), Length of Chord (L), External Distance (E) Apex Distance, Chainage of Tangent points, Intermediate Chord Length- For 1st chord, For 2nd to (n-1) chord, For Last chord, No of Intermediate Chord
Topics
In traverse survey, latitude and departure, checks in a closed traverse, closing error, relative precision, bowditch’s rule, transit rule are details discuss.
In setting out of circular curve we details discuss offsets from long chord, offset from tangent, offset from chord produced in linear method & tape & theodolite/rankine method / tangential / deflection angles, two theodolite method, tachometer method in angular method.