Symbols

Symbols and their meaning for railway construction

Symbol	Meaning of the symbol	Unit
a	Vertex distance with vertical curve	m
AA	Start of vertical curve
AE	End of vertical curve	m/s²
ar	Radial acceleration	m/s²
ap	Transverse acceleration
BA	Start of curve
BE	End of curve
BM	Centre of curve
BW	Change of radius
e	Distance between centres of lines	m
f	Displacement of the track curve compared with the tangent with a transition curve	mm
hf	Versine	mm
Δ h	Height difference	m
l	Longitudinal gradient	‰
k	Curvature of the track curve
l a	Length of the connecting curve with peaks and troughs	m
l b	Length of the circular curve (length of curve)	m
l g	Length of an intermediate piece of track	m
l n	Usable track length (also known as the UL)	m
l R	Length of the superelevation ramp	m
I RB	Length of the superelevation ramp according to Bloss	m
l RS	Length of the S-shaped superelevation ramp	m
l t	Tangent length	m
l ta	Tangent length of the vertical curve	m
l U	Length of transition curve, straight curvature line	m
l UB	Length of transition curve according to Bloss	m
l US	Length of transition curve, S shaped curve	m
l w	Length of turnout	m
ldSch	Last long sleeper	m
max	Attachment for highest value
min	Attachment for lowest value
1 : m	Inclination of the superelevation ramp
1 : n	Inclination of the turnout tangent
N	Inclination	m
HüNN	Height above normal zero
NW	Change in gradient	m
oA	Without details of the vertical gradient radius
r	Curve radius	m
r o	Radius of the branch-track of the turnout shape	m
r a	Vertical gradient radius of the change in gradient	m
r s	Radius of the main line of a curved turnout	m
r z	Radius of the branch-track of a curved turnout	m
reg	Attachment for basic value
RA	Start of ramp
reg	End of ramp
RM	Centre of ramp
s	Distance of the centres of the rail heads or line	mm; m
S	Line gradient as specified by DIN	‰
TS	Tangent intersection point
u	Superelevation of the outer rail	mm
u o	Equalising superelevation	mm
u f	Cant deficiency	mm
u u	Superelevation excess	mm
UA	Start of transition curve
UE	End of transition curve
UM	Centre of transition curve
v e	Design speed	km/h
WA	Start of turnout
WE	End of turnout
WTS	Point of intersection of the turnout tangents
zul	Attachment for permissible value