Porous Spatial Concrete Structures Generated Using Frozen Sand Formwork

One of the most distinctive properties of concrete is its ability to take nearly any shape while being processed in a liquid state and retain that shape upon hardening. Thus, the variety and complexity of concrete structures are virtually unlimited. However, nowadays concrete continues to be used mainly for simple volumetric objects, with the geometrical complexity being mainly constrained by the design and production of the formwork. In order to allow for more complex geometries, new formwork methods should be developed. In the framework of a research project on formwork methods for concrete, conducted at the Institute for Lightweight Structures and Conceptual Design (ILEK) at the University of Stuttgart, a new method called Hydroplotting was developed and tested. The present study provides a general description of the method and discusses its potential for the fabrication of concrete objects with a high geometrical complexity.