Overpass

A connecting ramp is the road that enables the transition from one to another highway at higher free transport hubs such as highway intersections, highway triangles or highway bifurcations.

Depending on the design and purpose of the node different variants of connecting ramps are used, which are crucial for the description of the construction of a motorway junction or triangle. In addition to the volume of traffic and the cost of safety is also an issue for the selection. For example, tight curves can be avoided without the transport is previously hampered by an exit. Therefore, the indirect connection ramp is rarely used in highway triangles.

Ramp groups

When viewed from two different ramp ramps compound groups can be distinguished.

• Ramp Group 1 - connection between highways ( free plan - Plan Free)
• Ramp Group 2 - Connection between the following streets ( free plan - Plan DC )

Direct connection ramp

A direct link is given when no other road needs to be crossed over or. Direct connection ramps, also called Tangentialrampe or Tangentialfahrbahn, only when turning right (for left-hand traffic only when turning left ) are possible and are available for all common types of nodes. Since no bridges have to be built and a drive-through at high speed is possible, there is the right turn no sensible alternative.

In unadjusted tangents the ramp runs at a steady 90 ° arc, while custom design the course of another ramp is followed. The adapted form is space-saving, but forced to decrease speed. Therefore, this variant is selected only if the space do not allow a non-conformist ramp function.

Semi- Direct connection ramp

A connection ramp to turn left (used in the right) as a semi- direct, which crosses under both highways on or off. If both highways cross, called the building also flyer ( Overfly ). As with the direct connection ramp high speeds are possible, but a complex or two less complex bridge structures depending on the leadership needed. This form requires a lot of space, provided that the traffic flow will be slowed down as little as possible, as large curve radii are needed. Through the bridges it is also costly.

It usually is only used when the associated highways have high traffic density. In highway triangles it is more common than at highway intersections to slow the main traffic flow as little as possible. The course of a semi-direct connection ramp depends largely on the type of the node.

Indirect connection ramp

In the indirect connection that is used to turn left, in contrast to the semi-direct variant no additional bridge structure is required. It runs mostly within a direct or semi-direct connection ramp, whereby the space requirement is very low. However, the traffic flow is strongly decelerated by the tight turning radius.

This form, which is also referred to as a " loop " or "ear" ( hence the name loop ramp) is to be found mainly at highway cruising in leaf clover shape or highway triangles in trumpet shape. It is the most common design for left turns at intersections in Germany. In high-frequency connections it is increasingly being replaced by a semi-direct connection ramp.