Facing concrete shells of sandwich walls under thermal loads

Facing concrete shells of sandwich walls under thermal loads. Within the framework of a research project funded by the Zukunft Bau research initiative of the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB), the Chair of Concrete and Masonry Structures of the Technical University of Munich (TUM) performs extensive thermal investigations on precast concrete sandwich wall panels with different facing shells taking in to account numerous boundary conditions. So far, building facades made of precast concrete sandwich panels are mainly realized by utilizing reinforced concrete members with a facing shell thickness of about 70 to 100 mm. Among other things, the thickness results from the required concrete cover to protect the reinforcing steel against corrosion permantly. By applying recent developments such as e.g. textile reinforcement and high performance concrete it is possible to build versatile facing shells, which thanks to the corrosion-resistant textile reinforcement and the achievable high strength may be designed with a reduced shell thickness of about 20 to 30 mm. With respect to this perspective, the aim of the above mentioned research project is to both numerically and experimentally derive realistic temperature values and gradients and provide an appropriate design approach for engineering practice. Hereby, in addition to various numerical analyses, the main focus is laid on the development of a full-scale in-situ test setup and the investigation of the actual temperature behavior of large facing shells with a thickness of 30 and 80 mm respectively over one entire weather period (365 days). Complementary laboratory investigations by means of a project-specifically developed multifunctional climate chamber (simulation of different weather scenarios) conclude the research project. © 2018, Ernst und Sohn. All rights reserved.