Optimisation and durability in fabric cast 'Double T' beams

By replacing orthogonal concrete moulds with a system formed of flexible sheets of fabric it is possible to construct optimised, variable cross section concrete elements that can provide material savings of up to 40% when compared to an equivalent strength prismatic member, and thereby offer the potential for significant embodied energy savings in new concrete structures.

This paper presents the salient results of two sets of tests recently undertaken at the Building Research Establishment Centre for Innovative Construction Materials (BRE CICM) at the University of Bath that considered 1) the design, optimisation and construction of 4m span double ‘T’ beams and 2) the surface properties of concrete cast into a permeable fabric mould. The results of these tests demonstrate how a fabric formwork construction system may be used to facilitate a sustainable future for concrete construction, providing a design method by which structurally optimised elements may be cast in an economical manner while also providing significant durability and visual benefits that combined provide an advantageous whole-life performance for fabric formed concrete that is unmatched by many other construction systems.