4.2.2.2.10 Viennese Bend Transition Segment
The Viennese Bend (R) transition segment is a kinematic high performance transition. The horizontal curvature is assembled by the baseformula and a term depending on the height of the gravity center line relative to the track plane and by the applied cant values at the start and the end of the segment.
The x/y coordinates can be calculated using a 7th order polynominal spiral.
The following diagram shows the generic classes and relationships used when applying this concept.
G
IfcCurveSegment
IfcCurveSegment
LayerAssignment
[0:1]
StyledByItem
[0:1]
1. Transition
[1:1]
UsingCurves
[1:?]
2. Placement
[1:1]
3. SegmentStart
[1:1]
4. SegmentLength
[1:1]
5. ParentCurve
[1:1]
IfcSeventhOrderPolynomialSpiral
IfcSeventhOrderPolynomialSpiral
LayerAssignment
[0:1]
StyledByItem
[0:1]
1. Position
[1:1]
2. SepticTerm
[1:1]
3. SexticTerm
[0:1]
4. QuinticTerm
[0:1]
5. QuarticTerm
[0:1]
6. CubicTerm
[0:1]
7. QuadraticTerm
[0:1]
8. LinearTerm
[0:1]
9. ConstantTerm
[0:1]
IfcCurveSegment :ParentCurve1->IfcSeventhOrderPolynomialSpiral :IfcSeventhOrderPolynomialSpiral0
IfcLengthMeasure_0
IfcLengthMeasure
IfcCurveSegment :SegmentStart1->IfcLengthMeasure_0:IfcLengthMeasure0
IfcLengthMeasure_1
IfcLengthMeasure
IfcCurveSegment :SegmentLength1->IfcLengthMeasure_1:IfcLengthMeasure0
IfcSeventhOrderPolynomialSpiral :QuadraticTerm1->IfcLengthMeasure_0:IfcLengthMeasure0
IfcSeventhOrderPolynomialSpiral :CubicTerm1->IfcLengthMeasure_1:IfcLengthMeasure0
IfcReal
IfcReal
IfcSeventhOrderPolynomialSpiral :ConstantTerm1->IfcReal :IfcReal0
IfcLengthMeasure_2
IfcLengthMeasure
IfcSeventhOrderPolynomialSpiral :QuarticTerm1->IfcLengthMeasure_2:IfcLengthMeasure0
IfcLengthMeasure_3
IfcLengthMeasure
IfcSeventhOrderPolynomialSpiral :QuinticTerm1->IfcLengthMeasure_3:IfcLengthMeasure0
IfcLengthMeasure_4
IfcLengthMeasure
IfcSeventhOrderPolynomialSpiral :SexticTerm1->IfcLengthMeasure_4:IfcLengthMeasure0
IfcLengthMeasure_5
IfcLengthMeasure
IfcSeventhOrderPolynomialSpiral :SepticTerm1->IfcLengthMeasure_5:IfcLengthMeasure0
Figure 4.2.2.2.10.A