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This paper deals with the design, production and monitoring of a bio-composite footbridge with a span of 14 m across the river Dommel in the city of Eindhoven, the Netherlands. The specific bio-composite material that was used for this research is a Natural Fibre Reinforced Bio-Polymer (NFRBP). The goal of the research is to prove that NFRBP can be applied as a load-bearing structure in an outdoor environment. For this purpose, a multidisciplinary team of academic researchers from two universities and from the Centre of Expertise Biobased Economy, together with a manufacturer from the NFRBP industry, have developed a feasible design that could be produced in a short period of time and within a limited budget. The footbridge was designed, built and installed within less than one year. In the two years after the installation of the footbridge, the structural behaviour of the bridge was monitored by means of optical fibre glass strands, integrated within the structure, with the purpose of measuring deformations and change in elasticity that occur over time.

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Natural fiber-reinforced composites (NFRCs) are expected to find growing applications in near future, especially in Europe where stringent environmental codes are being legislated and public pressure for their enforcement is increasing. Study has shown that NFRCs are also gaining recognition among civil engineers as a viable alternative to traditional materials for use as concrete reinforcement in load-bearing structural members as in building frames and bridge decks. The present review strives to provide a brief overview of NFRCs, state-of-the-art developments in their manufacture, and examples of their structural applications. Another aspect of the review involves investigation of the challenges facing the use of fiber composite materials in civil engineering. These include the high manufacturing costs, difficulties associated with appraisal of its potential benefits, uncertainties about their properties, lack of understanding among civil engineers of the material and its service life, and the relatively small battery of standards developed for the composite industry. Finally, the study will conclude with the prospects of bio-composite applications and the emerging trends in novel bio-composites for future structural applications.

Increasing importance is being attached to materials in the life-cycle of a building. In the Netherlands, material life-cycle assessments (LCA) are now mandatory for almost all new buildings, on which basis the building is then awarded a building environmental performance or MPG [Milieuprestatie Gebouwen] score. The objective of this study is to reduce the environmental-economic (shadow) costs of precast reinforced concrete (RC) beams in a conventional Dutch office building, thereby improving its MPG score. Two main optimizations are introduced: first, the amount of concrete is reduced, designing a cavity in the cross-section of the beam; second, part of the reinforcement is replaced with a fibre reinforced polymer (FRP) tube. The structural calculations draw from a combination of several codes and FRP recommendations. Hollow FRP-RC beams (with an elongated oval cavity), and flax, glass, and kenaf fibre tubes yielded the lowest shadow costs. In particular, the flax tube obtained shadow costs that were 39% lower than those of the hollow RC beam (with an elongated oval cavity); which also contributed to decreasing the shadow costs of other building components (e.g., facade), thereby reducing the MPG score of the building. However, this study also shows that it is important to select the right type of FRP as hemp fibre tubes resulted in a 98% increase in shadow costs.