Composite Façade Elements with Self-Cleaning Surface made of UltraHigh-Performance Concrete (UHPC)

In the framework of the European project H-House various concrete facade elements were developed with the aim to ensure a long service life by combining a very durable material with self-cleaning properties. The facade elements presented are made of a shell of UHPC filled with blocks of aerated autoclaved concrete as insulating material. Self-cleaning properties were realized amongst others by imprinting a microstructure into the surface during casting. The paper focuses on selected technological aspects of the manufacturing process of prototypes which had to be performed in two concreting sections. Furthermore the challenges faced when upscaling the self-cleaning properties are addressed and the strategy to assess the self-cleaning properties by measuring the contact and the roll-off angel is presented. The results show that a successfull upscalaing process requires detailed planning and that the best results can often be achieved with a moderate work effort or material use.