Graphic concrete walls
In recent years, the use of concrete as architectural element, in addition to application in the sector of structural-engineering-related construction, is experiencing a true renaissance. The reasons for this revival, apart from the advances made in concrete technology and reinforcement techniques, also include production methods. For project “I2”– conceived and implemented within the scope of the German Federal Garden Show 2019 in Heilbronn –recent manufacturing methods of this kind were utilized and the architectural freedom of design in graphically staged concrete façade surfaces were fully exploited. A building in the urban exhibition Neckarbogen City Quarter provided the framework here.
The graphic concrete façade panels and planters depict on the circumference of six stories the recurrent graphic pattern of blades of grass swaying in the wind. The interplay of the graphic drawing elements with grass planted in the façade planters results in an impressive overall picture with reduced, clean lines.
In planning, owing to the graphic concrete surface, it was necessary to consider not only the surfaces of the elements, but also the thickness of the shells and the joint widths. The printed patterns designed were applied to large-surface paper strips by screen printing far in advance of the actual production start. The clou of the method: instead of the customary ink, a chemical concrete retarding agent was used. This partially prevents formation of a hardened cement layer, typical to concrete, during subsequent casting of the concrete. After striking the structural element with high-pressure water, the areas of the surfaces treated in this manner were simply washed out and the concrete matrix and aggregate exposed. The impression of a graphically designed concrete surface results from the contrast in color and structure of the smooth-formed layer of hardened cement and the exposed matrix. The result can be seen along Theodor Fischer Street, also after the German Federal Garden Show.
