Ultra-High-Performance Concrete (UHPC) is characterized by outstanding compressive strength, durability, and formability, making it ideal for the strengthening and rehabilitation of bridges. UHPC components - such as hybrid anchor plates, truss elements (e.g., CoBeam), bridge bearings, and custom-fabricated anchorage or deviation blocks - can replace conventional steel or reinforced concrete parts. Advantages include compact design, reduced weight, enhanced durability, and significant CO2 savings. UHPC allows for precise adaptation to complex geometries and is economically viable even in small quantities. A key factor in its practical use is product approval: in 2025, the first general technical approval (abZ) for UHPC components in prestressing systems was granted in Germany. This marks a milestone toward broader market adoption. The presented applications demonstrate UHPC's potential as an innovative and sustainable alternative to traditional construction materials. Future developments are expected to focus on standardization, which will facilitate quicker and more widespread implementation in bridge construction.

Durch die Osterweiterung der Europäischen Union wird zusätzlich zum Transitverkehr der Zielund Quellverkehr zwischen dem zentral gelegenen Deutschland und den osteuropäischen Nachbarn stark zunehmen. Nach [1] ist mit einem überproportionalen Anwachsen des grenzüberschreitenden Personenund Güterverkehrs von und nach Osteuropa um 40 % (Pkw) bzw. 250 % (Lkw) von 1997 bis 2015 zu rechnen. Aus diesem Grund und aufgrund erwarteter Rückstauungen der LkWs wurde bei der grenznah zu Tschechien gelegenen Spannbetonbrücke über das Röslautal bei Schirnding im Zuge der Bundesstraße 303 die Anordnung eines zusätzlichen Fahrstreifens geplant und schließlich in 2003 umgesetzt [2]. Abbildung 1 zeigt den Querschnitt des 1995 fertig gestellten vierfeldrigen Bauwerks mit alter und neuer Nutzung. Die rot markierten Bereiche zeigen die erforderlichen Änderungen. Aufgrund der reduzierten Kappenbreite mussten Querneigung und Entwässerung angepasst werden. Die Stahlleitplanken wurden durch Betonwände ersetzt.

The paper presents experiences with damages that occurred when using external tendons. Reason for these damages could be both technical deficiencies of a tendon system (system = components, design, corrosion protection, installation, stressing etc.) or simply human mistakes. Damages often could occur at deviators and anchorages, since forces are transferred to the structure there and the tendon is loaded in transverse direction. Damages will be presented, explained (why it is a damage), which measure had been taken and of course also advice for the future (lessons learned). The damages occurred on site or during testing of external tendon systems. Hence, the paper shall help the reader/attendant to understand sensitivity of external tendons. Furthermore, to these damages experiences with replacement (mainly cutting of the old tendon) of external tendons with flexible filler mass are shared. "Experience" focusses mainly on the de-installation, re-installation, grouting and stressing process. Topics that will be covered are: Improper design and/or installation of deviators and subsequent damages to the tendon sheath Torsional strand failure due to improper deviation at stressing anchor Limitations of the tendon path Deficient encapsulation of the prestressing steel Tendon force measurement options

Die Illerbrucke Egelsee ist Teil der A7 und wurde 1969-1970 als semi-integrales, stark schiefwinkliges Spannbetonbauwerk uber zwei Felder mit einzelligem Kastenquerschnitt erstellt. Das Bauwerk wurde fur das Verkehrslastmodell LM1 nachgerechnet; hierbei ergaben sich umfangreiche Defizite. Aufgrund des geplanten 6-spurigen Ausbaus der A7 wurde zur Minimierung der baulichen Ertuchtigungsmasnahmen das Ziellastniveau auf die BK60/30 und die Nutzungsdauer auf 30 Jahre (Nachweisklasse C) reduziert. Zur Sicherstellung der Tragfahigkeit des Bauwerks bis zum Ersatzneubaus konnte so der Verstarkungsumfang auf eine Ertuchtigung der Gurtanschlussbewehrung der Bodenplatte an die Stege mit Querspanngliedern sowie der Querkrafttragfahigkeit des Pfeilerfundamentes beschrankt werden. Herausforderung bei der Planung und Umsetzung der Masnahme war die starke Schwiefwinkligkeit des Bauwerks, die sehr enge und komplexe Geometrie der Bestandsspannglieder der Stege und – damit verbunden – die erforderliche hohe Genauigkeit beim Herstellen der geneigten Kernbohrungen, um nicht nur eine Schadigung der Bestandsspannglieder, sondern auch der Bugelbewehrung auszuschliesen. Die Querspannglieder wurden z.T. im nachtraglichen Verbund innerhalb der Bodenplatte sowie als externe Spannglieder bodenplattennah durch die Stege bzw. unterhalb des Bauwerks gefuhrt, wobei die Verankerung im letztgenannten Fall uber eine Stahlkonstruktion an der Ausenseite der Stege erfolgte. Die Ertuchtigung des Pfeilerfundamentes ist mithilfe von Verbundankerschrauben als nachtragliche Schubbewehrung geplant. Die Ertuchtigung des Uberbaus wurde im Jahr 2019 und 2020 ausgefuhrt; die Verstarkung des Pfeilerfundamentes ist fur 2021 vorgesehen.

Kuhbrücke/Hildesheim is an unreinforced concrete arch bridge built in 1910. The bridge has been strengthened in 2016 to upgrade the capacity carrying vehicles with maximum weight from 3 ton to 40 ton. The historic arch and the foundations are further used. New webs had been added by horizontal prestressing to the arch. A bar post-tensioning system (50 mm) has been used with innovative and very durable Ultra High Performance Concrete (UHPC) anchor plates (Hybridanker). Finally a reinforced concrete deck slab has been added to create a kind of box section. To reduce thermal stresses in the integral bridge a bridge deck cooling systems has been installed. To verify the efficiency of the cooling many temperature sensors had been placed. The measure has been finished in June 2016 and bridge can be used now by 40 ton trucks. The article presents the strengthening concept, the construction and finally the innovative aspects (UHPC anchor plates, bridge deck cooling).

Sprayed concrete (or ‘shotcrete’) is often used as a lining for tunnels, particularly where the low mobilisation cost and flexibility of geometry make segmental tunnel linings uncompetitive. The early strength gain of the shotcrete is a crucial aspect to ensure there is effective ground support and to ensure the safety of operatives. Currently, strength monitoring is achieved by needle penetrometer and stud-driving tests according to EN 14488-2 (2006). These tests are very local and hence may not be representative, they are time consuming, and to avoid the risk of falling fresh shotcrete, these tests are often performed in panels sprayed subsequent to spraying the lining.

The new railway bridge over the Leuvensevaart within Spoorbypass Mechelen (Belgium) is a single span integral bridge/frame. The steel superstructure needs to be connected to the abutments with very high loads. This is realized with prestressing thread bars up to 75 mm in diameter. The anchorages of the bars needed extremely little space and arrangement of confining spirals was nearly impossible. For durability reasons and geometrical flexibility (inclination) also the outer anchorages that stress the steel structure to the RC abutment are made of UHPC. This article presents in brief the bridge and focuses on post-tensioning concept and details and UHPC anchor plates. The bridge is under construction and installation of post-tensioning bars and anchorages has been done in autumn 2016.

With the help of a non-destructive monitoring of two structures of the eastern ramp of the Kohlbrandbrucke, Hamburg, the danger of fatigue fracture of prestressing steel of coupling joints due to traffic and temperature loading has been assessed and evaluated.To this aim, dynamic measurements of the crack movements and of the temperature distribution over the cross section were carried out in the period August 2013 to August 2014.The aim of the monitoring was to detect the actual state of the structure and to specify in the theoretical verification concept conservatively assumed parameters (e.g. local stress losses, temperature gradient) by site and object specific approaches. Within the framework of this paper the developed monitoring concept, the measurement results and their implementation in the theoretic verification are introduced and discussed.

First application of composite anchor plates ("Hybridanker") for strengthening a Rhine lock with permanent ground anchorsPrefabricated composite anchor plates are using high performance concrete and steel or carbon fibres for load transfer of tendon forces (post-tensioning tendons, ground anchors). First application of the Hybridanker-type has been realized at the Rhine lock in Iffezheim, where permanent multistrand ground anchors had been installed. The prefabricated Hybridanker-solution allowed a durable and compact load transfer to old, unreinforced concrete.

UHPC is used to replace steel for anchoring of tendons. Massive steel plates are usually used to transfer the load locally into the structure. The higher the load and the smaller the resistance of the structure (e.g. small concrete strength, little or no bursting reinforcement) the larger the steel plates, especially for ground anchor applications and strengthening measures. A special type of hybrid anchorage or CFT-anchor plate (concrete filled steel tube) has been developed that is more economical, less steel consuming and significantly lighter. The basic idea is to fill a steel tube with high performance concrete which allows easy forming of the duct channel and contact zone with anchor nuts (e.g. for thread bars). This article is about the basic principle, several phases of development including testing according to European Technical Approval Guideline for Post Tensioning Kits ETAG 013 and fmally presents a case study for strengthening a box girder bridge with external cables.

The bridge design with external Post-tensioning has been established and applied successfully in the last two decades. In Germany consequently the development moved towards using unbonded tendons also internally. In comparison with solely externally prestressed structures the lever arm in box girders can be improved significantly and the application is also interesting for massive cross section design like T-beams. On basis of its established SUSPA-Wire Ex system for external Post-tensioning DSI has developed SUSPA-Wire internal with a fully restressable and replaceable tendon meeting the requirements of a suitable PT-system for the new concept of PC structures. Several pilot projects have been carried out in the last years. The replaceability has been proven recently on a road bridge project in South Germany on a tendon of some 84 m length. The insitu test has been supervised by an independent laboratory and additionally reviewed by an accredited expert.