Jvgdata transition curve

In normal head tracks, transition curves shall always be arranged to provide a smoother transition between straight track and circular curve or between two circular curves with different radius. Transition curves shall be carried out with linear change of curvature (clotoid). Transition curves shall be arranged on the line and on the normal main track within an operational location, but it is also recommended to be organised in: deviating main tracks where possible. The curves start and end in tangent points marked with cant signs on the inside of the foot of the outer rail with a maximum longitudinal deviation of 0.5 m. Transition curve is included as a track element in the description of track geometry and is part of the plane geometry, which also includes straight lines and circular curves. The track geometry represents the projected geometry and refers to the track center. The data product contains the radius of the transition curve in the tangent points, the type of geometric function, the length and the method used for the data capture. Type of geometry = R indicates that the transition curve has linear curvature change (clotoid) which is the most common type and the only one used in the construction of new tracks. Type of geometry = S indicates that the transition curve has curved the course of curvature (fourth degree parable). This type of transition curve is relatively rare and is not used in new construction. When the geometry has the Origin = G (measured geodetic) attribute, data is coordinated and comes from the GAD system or is transferred from the GEOSECMA system. The data product then has a high quality and can be used for all types of applications. At Origin = P (Pile Height Measured — Not Geodetically Measured), data is interpreted from machine measurement and only suitable for applications where low quality can be accepted. The data product has stretch distribution and connects to the network with reference to the nearest previous node and nearest previous kilometre board with distance in meters to both the start and end positions of the transition curve (=key points) in the direction of the track link. The object types Circular curve, transition curve, straight line and rail elevation together form the plane geometry and shall create an aggregate geometry description for all track links in the Swedish railway network. For the three object types Circular, Transitional and Straight Line, there is the Object’s total length (m) attribute which contains the length used to generate the lengths of track links and which forms the basis of the linear reference system for rail — the link length and track length apply.