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 levelling, we are details discuss about elevation & altitude, reduced level, mean sea level, bench marks(B.M), horizontal line, vertical line, level line, back sight reading, fore sight reading, intermediate sight reading, method to find reduced level, height of instrument, rise and fall method, inverted staff, correction required in levelling work, distance of visible horizon, reciprocal leveling, collimation error, angular / inclination error, sensitivity of bubble tube, the sensitivity of level tube increases with?.
In fundamentals of surveying (part-2), we details analysis about plan & map, scale, representation of scale- engineer’s scale, representation fraction (rf), graphical scale. Shrinkage factor or shrinkage ratio, error due to shrinkage of map, error due to wrong measuring scale, type of scales- plane scale, diagonal scale, vernier scale (direct vernier, retrograde vernier, extended vernier, double vernier).