Leica FlexLine plus - Page 105

FlexLine plus, Programs
105
Horizontal and
vertical geometry
elements combined

Start and end chainage and tangent points can be different for the horizontal and
vertical alignments.
Quadratic
parabola
A quadratic parabola has the advantage that the rate of change of grade
is constant, resulting in a "smoother" curve. A quadratic parabola has to
be defined by:
• Start chainage and start height of P1.
• End chainage and end height of P2.
• Parameter, or Length (L), grade of entry straight (Grade In) and grade
of exit straight (Grade Out).
P1 Start point
P2 End point
LLength
%Slope
Element Description
TSOX_114
P1
+%
-%
P2
L
TSOX_115
+%
-%
P1
P2
L
a = Horizontal alignment (top view)
R1 Radius 1
R2 Radius 2
a1 Straight
a2 Curve with R1
a3 Partial spiral with R1 and R2
a4 Curve with R2
a5 Spiral out with R2 and R=
a6 Straight
b = Vertical alignment (front view)
b1 Straight
b2 Curve
b3 Straight
b4 Parabola
b5 Straight
•Tangent point
TSOX_116
R
R1
R2
-%
+%
-%
b1
b2
b3
ab
b4
b5
a2
a3
a4 a5
a6
a1
∞