DELIVERABLE 2.8 - urban track

Figure 3.8
Bezogene Krümmung
8
6
4
2
0
-2
-4
-6
-8
D0208_STIB_M24.doc
TIP5-CT-2006-031312 Page 32 of 44
URBAN TRACK Issued: August 13, 2008
Quality checked and approved by project co-ordinator André Van Leuven
Alle Überhöhungsrampen - Krümmungen
0 0,2 0,4 0,6 0,8 1
All cant gradients - curvatures
Be zoge ne r W e g
Linear ramp
Bloss ram p
COS (Japanese) ram p
Helm ert (S chramm ) ramp
W atorek ram p
SIN ram p
Herbert's HT ram p
Viennese type HHM P7
© H asslin ger
The position of the ramp is directly built with the basic function. The first derivative is proportional to
the rail inclination angle and the angular velocity about roll axis, the second derivative is proportional to
the angular acceleration about roll axis and the bending moment about transverse axis in the rail, the
third derivative is proportional to the angular jerk about roll axis and the shear force in upright direction.
The smooth junction with the constant functions at each side can be proven.
To prove the superiority of this advanced curve design an ideal reproduction of conventional curves
(clothoid) with straight cant gradients was built and negotiated with a track recording train during
nightly downtimes. The track recording train conducted acceleration measurements in a series of
measuring runs. Then the curves were retamped to introduce the new alignment geometry (Viennese
Transition Curve and cant gradients) and the measuring runs repeated with the track recording train.
The following comprehensive deterministic and statistic evaluation clearly shows that vehicle movement
was improved by the new alignment geometry (see Illustration).