Production, aspects in construction practice and concrete technology

Dürnbach bridge pilot project – Germany’s first precast railway bridge made of UHPC, part 2

Conception and design of the railway bridge (Tegernsee-Bahn) in Dürnbach were reported in part 1 of the paper. Part 2 provides additional information on the production of the bridge at the precast plant and on the parameters in terms of concrete technology of the UHPC used.

The structural design of the prestressed and steel-fiber reinforced (2.5 Vol.-% of steel fibers, l/d = 12.7 mm/0.175 mm) precast concrete bridge resulted in a required strength class of C150/155 as well as an E modulus of approx. 48,000 /mm². The demanding requirements on the fresh concrete properties resulted from previous experiences gained by the manufacturer of precast elements, Max Bögl, with ultra-high performance concrete. According to that, the mixing time of the UHPC should be possibly below 5 min in the usual twin-shaft compulsory mixer of the precast plant. Self-compacting properties with a slump flow of at least 700 mm and a processing time of at least 90 min should be ensured. The coarse-grained UHPC (maximum grain size 8 mm, 10 Vol.-% of basalt) of the EFFIX PLUS compound of HeidelbergCement AG was used as mortar matrix in order to save silo capacities. This allowed achieving maximum mixing times of 120 sec. The concrete characteristics of the steel-fiber reinforced UHPC are shown in the table. The modular prestressing bed existing at Max Bögl was used for the production of the bridge slab of the pilot bridge, that is prestressed in longitudinal and transverse directions.

The driving route for the heavy goods and special transport for carrying the bridge slab dimensioning l x B = 6.50 m x 4.57 m to the installation site, using the fleet of Max Bögl, was agreed with the locally responsible site manager.

Related articles:

Issue 2019-02 Backgrounds and scientific support

Dürnbach bridge pilot project – Germany’s first precast railway bridge made of UHPC, part 1

Ultra-high performance fiber-reinforced concrete (UHPFRC) is characterized by an extremely dense structure and thus very high strengths as well as excellent durability properties. This enables slender...

Issue 2017-02 Precast elements in bridge construction

New developments and international examples

A large number of new bridges need to be built in conjunction with maintaining and expanding the transport infrastructure in Germany. Precast construction can make a major contribution to achieving...

Issue 2018-02 Modern concretes for precast bridges

State of the art in Germany and internationally

Generally speaking, the use of precast elements in bridge construction is a tried-and-tested method, which, in Germany, is usually restricted to combining structural precast elements with cast-in-situ...

Issue 2010-07 Powered by Eirich

Taxiway bridge for Fraport expansion

During the night of May 8th - 9th, the first bridge girders were installed for the link that will connect the existing airport facility with the new northwest runway. The precast elements are...


PCI announces 2016 PCI Journal Awards

The Precast/Prestressed Concrete Institute’s (PCI’s) Journal Awards Committee has named the winners of the 2016 PCI Journal awards. This year’s Martin P. Korn Award goes to Jay Holombo, Rick...