Vereinfachte Methoden zur Berechnung der dynamischen Antwort von Eisenbahnbrücken bei Zugüberfahrt

Simplified methods to calculate the dynamic response of railway‐bridges under crossing trains. In this paper, two different methods to calculate the dynamic response of single‐span bridges under moving forces are presented. The work is focused on beam bridges with constant cross‐section in underdamped condition. In the first method, referred to as “Impulse‐method”, the effective impulse resulting from the load is approximated by simple analytical functions. The bridge is modelled as a single degree of freedom system by means of modal analysis. For this simplified system describing bridge and load, closed analytical formulae to calculate the dynamic response can be set up. The “Impulse‐method” is exemplified by the HSLM‐A1 load train given in Eurocode 1 (EC1). In the second method the response spectrum analysis widely used in earthquake engineering is adopted for the present problem. The calculation of response spectra for beam bridges under the HSLM‐A load models is demonstrated. An example shows how this method is deployed.     

Neue Verbund‐Schrägseilbrücken (BW 29 und 4) im Zuge der BAB 30 – Nordumgehung Bad Oeynhausen

Zur Zeit befindet sich der Lückenschluss der BAB 30 als sogenannte Nordumgehung Bad Oeynhausen im Bau. In diesem Rahmen werden am östlichen und westlichen Ende der Nordumgehung die Bauwerke 29 und 4 erstellt. Hierbei handelt es sich um Schrägseilbrücken in Verbaundbauweise, welche architektonische Landmarken an den Enden der Nordumgehung Bad Oeynhausen setzen. Beide Bauwerke überführen die BAB 30 über den Fluss Werre. Die Stromöffnungen betragen ca. 68 m bzw. ca. 83 m und sind damit für Schrägseilbrücken vergleichsweise gering. Aufgrund der Lage im Krümmungsbereich, der örtlichen Randbedingungen (u. a. große Schiefe wegen des Kreuzungswinkels) sowie des FFH‐Status der Werre ergab sich im Rahmen der Entwurfsplanung eine anspruchsvolle Aufgabenstellung. Trotz eines ähnlichen Erscheinungsbildes unterscheiden sich beide Bauwerke jedoch maßgeblich in ihrer Konstruktion durch die Anzahl der Seilebenen und die Ausbildung der Seilquerträger. Der Aufsatz beschreibt die wesentlichen statisch‐konstruktiven Besonderheiten der Bauwerke aus Sicht der Entwurfsverfasser. New cable‐stayed bridges (Structure 29 and 4) in the course of the Autobahn A 30 – Northern bypass at Bad Oeynhausen. Closing a gap in the course of the Autobahn A 30, the Northern bypass at Bad Oeynhausen is currently under construction. Within this project two cable‐stayed bridges, Structure 29 and 4, are being constructed at the Western and Eastern ends of the bypass. The bridges are of composite construction and they have been architecturally designed to form landmarks at the respective ends of the Bad Oeynhausen bypass. Both structures carry the Autobahn A 30 across the river Werre. The main spans measure 68 m and 83 m respectively and are thus fairly short for cable‐stayed bridges. Due to the location in curved sections of the Autobahn, local constraints (such as a large skew because of the crossing angle) and the Werre being a nature reserve with FFH status, the structural design has been a demanding task. In spite of having a similar appearance both structures differ significantly in number of cable planes and the construction of the transversal girder for cable anchorages. This article describes the distinctive features of both bridges from a static and structural point‐of‐view.     

Der Stabbogen bei stählernen Straßenbrücken – Entwicklungstendenzen der letzten 50 Jahre – Teil I

The strut arch in using of steel road bridges mainly in Germany – trends of developments into the last 50 years. By the presentation is given a survey about the development of the designing the arch construction for steel road bridges inclusive the constructive details. In the detail are considerd the suspensions with their connections, the cross‐sections of the arch, springing arch, arch model and the roadway‐constructions into different phases. At last of the investigation are presented some typical erection‐examples.     

Der Stabbogen bei stählernen Straßenbrücken – Entwicklungstendenzen der letzten 50 Jahre – Teil II – Fortsetzung aus Heft 2/2005 und Schluß

The strut arch in using of steel road bridges mainly in Germany – trends of developments into the last 50 years. By the presentation is given a survey about the development of the designing the arch construction for steel road bridges inclusive the constructive details. In the detail are considerd the suspensions with their connections, the cross sections of the arch, springing arch, arch model and the roadway‐constructions into different phases. At last of the investigation are presented some typical erection‐examples.