Static and Dynamic Load Test of Libeň Bridge Over Vltava River in Prague and Concept of Repair

The Libeň bridge in Prague is a cultural and technical heritage of concrete construction of the beginning from the twentieth century. The bridge was designed by architect Pavel Janák, the founder of cubism in architecture. According to experts, the Libeň bridge is the only example of cubist morphology application on the bridge structure. Evaluation of Libeň bridge structural condition is an up-to-date topic leading to decision whether this bridge should be repaired or replaced by a new bridge. This article deals with the static and dynamic load testing in comparison with following creation and validation of the FEA model for load carrying capacity assessment of the Libeň Bridge and possible way of reconstruction. Paper deals with crucial procedures for FEA model validation of this backfilled arched concrete structure with a focus on the static characteristic of the structure. Article deals with reconstruction of the vault part of the Libeň Bridge using R-UHPFRC in terms of static operation. It focuses on the two basic problems of the bridge, the solution to increase the bearing capacity of the vault arches and to increase the bearing capacity of the foundations under pillars. The concept of repair is based on extensive diagnostic surveys conducted in 2017. The concept of structural enhancement is based on adding new thin layer of R-UHPFRC (reinforced, ultra-high performance concrete) on the upper vault surface. Concrete bridge structures are exposed to extreme effects of aggressive environmental influences, especially chlorides, which leads to damaging of most exposed bridge components a long time before their service life. UHPFRC material is suitable for repairs of these structures and especially due to its impermeability and high resistance