From flat sheet to three-dimensional non-planar concrete formwork: a composite system integrating Kerf bending and curve-folding for the fabrication of architectural non-standard concrete elements

Abstract

Despite the recent development in digital technologies, materials innovations, and production processes; the construction industry, particularly in the field of concrete formwork, continues to undergo development. Although concrete, the most widely used material globally, is criticized for its carbon emissions, it offers unparalleled potential for achieving geometric freedom in the creation of complex, non-planar, and innovative architectural designs. Non planar forms can also be more structurally efficient and provide a reduced carbon footprint when compared with rectilinear forms. Across the range of concrete construction, the basic nature of the material is inherently simple but the complexity lies in the process of making.

Even with extensive ongoing research within the context of design + construction of non-planar concrete, it is still challenging to construct curved concrete forms. This is due to the complexity and high cost of non-standard formwork. Furthermore, curved moulds require a great deal of material, time, and labour to use effectively; and are difficult to reuse. This presents a substantial source of waste. With the aim of overcoming the current challenges related to site processes, environmental sustainability, and construction cost, this research proposes a new formwork system integrating kerf bending and curve-folding approaches for constructing curved concrete elements. The system also addresses the needs of contractors and builders who understand the use of conventional planar formwork, but lack access to or proficiency in advanced digital technologies. By enhancing the flexibility of commonly used two dimensional materials in traditional formwork construction, mainly plywood, to enable the creation of three-dimensional forms, this novel approach to formwork has the potential to contribute to more efficient and sustainable concrete construction.

Practical experiments, prototype design development, and construction of curved concrete forms served as the basis for validating this concept.

Additionally, qualitative analysis of case studies and industry interviews provided insights into real-world applications and further supported the development of the formwork system.

Through iterative testing, refinement, and feedback loops, the research sought to develop a complete construction process that demonstrated that it is possible to fabricate structurally efficient, non-standard concrete forms through a practical, user-friendly, and industry-feasible methods while at the same time reducing waste, lowering costs, enhancing sustainability, and expanding architectural potential.