Fly-over

from Wikipedia, the free encyclopedia

As Flyover or Flyover (sometimes Overfly ) are generally structures of road transport referred to other roads "skim" (Engl. To fly over ) or bridge. In the simplest case, it is a connection ramp that guides the main flow of traffic over an intersection without a plan ; However, there are also complex multi-storey structures (e.g. in motorway junctions ). The goal is a better flow of traffic and increased safety. More specifically, a fly-over is a temporary structure that bridges a length of road section in need of repair while the actual traffic route underneath is being repaired.

Mobile steel construction in Austria

Bridging expansion joint construction sites on motorway bridges
Renewal of a road expansion joint under flyover

Fly Over in Austria refers to a 106 m long, transportable steel structure made of individual elements for the dome-like bridging of short construction sites on motorway bridges. It was developed in Austria for the purpose of renewing the more than 40 “roadway expansion joint constructions” for the most heavily used motorway section of the A23 (180,000 vehicles / day) to eliminate traffic blackouts in Vienna during the construction period.

development

Renewing a roadway expansion joint normally takes a few weeks. With this approach, the severest impairment of the efficiency of the A23 through lane closures with high economic damage due to loss of time, delays in deadlines, increased fuel consumption, environmental and local burdens and much more of more than 14 million euros for each of the 40 construction sites due to traffic jams would have been expected.

In order to eliminate this scenario, a completely new technical solution was developed with the idea of ​​Walter Hufnagel, then head of the bridge construction department of the City of Vienna, with the steel construction company Waagner Biro , the engineering office A. Pauser and AXIS engineering services and called "Fly Over".

The idea was to bridge every expansion joint construction site over the entire width of the bridge with three lanes and the following basic functions, which were used as a basis for further planning:

  • offer sufficient working space and a working height of predominantly 1.90 m
  • The lowest possible dead weight to avoid damage to the bridges
  • Construction within one night and dismantling within one night
  • During installation, one of three lanes must always be available for traffic
  • Safe to drive on up to a speed of 80 km / h
  • common bridge security standard
  • Possibility of mounting in curves, knolls and on the slopes of the A23 without compromising safety

In order for these basic functions to be fulfilled, an approx. 106 m long, approx. 2 m high dome-like spanning three lanes of 69 individual elements with the following features was developed in a planning period of almost two years:

  • Bridge device in a modular system with quick connections for quick assembly and dismantling in modular design for universal use for three lanes.
  • Sophisticated logistics system for delivery and removal as well as assembly, dismantling and assembly in one night
  • Assembly in lanes with partial maintenance of traffic
  • The load-bearing core of the auxiliary bridge are trestles or “truss tables” that carry 23 decks of the same size per lane, connect and stabilize the system and give it the dome-like shape. They are stable and do not have to be screwed onto the roadway. They distribute the loads evenly in the roadway and bridge through footplates.
  • Lightweight construction in special steels

In order to ensure that this 106 m long bridging device also works, the test set-up of a lane was commissioned before its first use in the spring of 1999. Finally, all those involved, stakeholders and media representatives were invited to a test drive with a heavy truck and extensive information about the fly-over and the construction processes on the south-east tangent. Since this was a technical novelty for a highly sensitive traffic system, it was particularly important to provide proof of performance before the first commissioning in order to ensure sustainable acceptance. With acquisition costs of approx. 150,000 € for planning and production, the fly over is a comparatively cheap measure with great effect and high value. The Fly Over offers safe and noise-reduced working conditions for the work underneath, the renewal of the roadway expansion joints on the bridges. For the work itself, this created optimal conditions for the highest quality of execution - a complete expansion joint construction can thus be renewed in peace and concentration within a few weeks without any traffic disruption. This extraordinary idea was nominated for the Austrian State Prize for Consulting in 2000.

Fly-over use

The fly-over is used by the ASFINAG -autobahngesellschaft. This construction was first used in 1999 on the Austrian motorway Südosttangente Wien (A23). The fly-over was later expanded by one lane to four. The result is around 106 meters long and 13.4 meters wide. If the fly-over is set up for four lanes, 16 articulated vehicles are required to transport the individual parts, which weigh around 300 tons. Two cranes with a lifting capacity of 50 tons and around 250 lifting operations are necessary for erection and dismantling in one night. The motorway remains passable in one lane.

A23 in Vienna

  • 1999 The fly-over was first used in 1999 on the A23 in the Sankt Marx area . It was set up there on the night of July 10th to 11th. The construction work to replace the expansion joint in need of renovation lasted four weeks. The fly-over was dismantled on the night of August 6th and 7th and rebuilt on the opposite lane the following night. The renovation work was completed on September 3, 1999.
  • 2000 The fly-over was set up on the night of July 7th to 8th, 2000 on the northbound lane. The last dismantling of the auxiliary bridge for the 2000 season took place between September 1 and 2, 2000. In total, the fly-over was erected and dismantled three times during this period.
  • 2001 In the summer of 2001, the fly-over was used at the closed Simmering exit . It was then used on Hochstraße Sankt Marx until the end of October 2001.
  • 2002 Between mid-June 2002 and mid-October 2002 the fly-over was again in action between Simmering and Sankt Marx for about ten weeks.
  • 2004 In 2004, work was carried out between the beginning of April and the end of September 2004 at three points at the Landstrasse junction on both lanes .
  • 2005 In 2005 the fly-over was set up for the first time this year on the night of June 11th to 12th at the Kaisermühlen node . After three changes, it was dismantled on the night of September 28th to 29th, 2005.
  • 2009 In August 2009 the fly-over was set up at the Kaisermühlen junction on the connecting ramp from the A22 to the Prater Bridge .
  • 2010 The fly-over was in use between the Kaisermühlen node and the Stadlau tunnel in the north direction. It was then set up in the direction of travel south.
  • 2012 After a two-year break, the fly-over was set up on the southeast bypass at the Prater junction to swap the expansion joints to the north. In the summer of the following year, it will then be used in the opposite direction.
  • 2014 This time the fly-over was used twice. Both times in the direction of travel south between the Landstrasse junction and the closed Simmering exit, the work takes 5 weeks each.
  • 2015 In the summer months, the fly-over was set up in two places. At the closed Simmering exit in the north and on the four lanes of the motorway in front of the exit.

Austria

Between March and April 2006 the fly-over was in use in Styria on the A9 ( Pyhrn Autobahn , Sankt Stephan valley crossing in the Gratkorn area in the direction of Graz ).

Netherlands

During the years in which the fly-over was in use in Vienna, there were always inquiries from abroad, but so far hardly any orders. Between May and September 2005 z. B. On the Dutch A12 motorway near Amsterdam, nine expansion joints were completely renovated with the help of a flyover.

literature

  • Gerald Luza, Walter Hufnagel, Hermann Reiter: The FLY Over-Rampe - dilation exchange while maintaining traffic . In: Bauingenieur 76, 2001, pp. 537-542 ( digitized [PDF; 544 kB]).

Individual evidence

  1. ↑ Fly-over in Duden online.
  2. ↑ "KURIER" VIENNA; August 14, 2000, page 10
  3. ↑ "WIEN AKTUELL", 19th year, No. 12, from July 22, 1999
  4. ↑ Fly-over structure: delays on Tangente , ORF of July 18, 2015

Web links

Commons : Fly-over  - collection of images, videos and audio files