Trade Journals for the Concrete Industry

This article presents the design and construction of FlexiArchTM, a novel pre-cast bridge system which has been developed under a Knowledge Transfer Partnership between Macrete Ltd. and Queen’s University Belfast. Knowledge Transfer Partnerships is a UK-wide programme supported by government and assisting businesses to improve their competitiveness and productivity through the better use of knowledge, technology and skills that reside within the UK Knowledge Base. The Partners, Macrete and the University, are now on their third KTP to create FlexiArch design tools, and develop a range of complex geometry Flexiarch systems for new bridges and to strengthen existing arch bridges. However, this article discusses the successful development and construction of Tievenameena bridge which was the first FlexiArch bridge for the Department of Regional Development. The design philosophy is in line with advice given by the UK Highways Agency for Design for Durability (BD 57/01 & BA 57/01). This bridge spans 5m but the system is capable of spanning up to 15m. The arch is based upon the same principles as traditional stone masonry arches dating from Roman times but without the need for labour intensive temporary supports or skilled stone masons. The arch ring uses plain structural elements and eliminates the use of corrodible structural reinforcement as recommended for improved Whole Life Performance of concrete bridges. The arch is made of pre-cast concrete voussoirs and is transported in ‘flat-pack’ form. The construction phase makes use of a low grade polymeric reinforcement to support the self weight of the arch ring during lifting. Once in the arch form, it behaves as a masonry arch bridge carrying bridge loading effectively through compression. The FlexiArch system has been developed under a Knowledge Transfer Partnership between Queen’s University and Macrete Ltd and it should be noted that it is patent protected.