JEC COMPOSITES MAGAZINE - Issue #35 - September 2007 - 28

Trends g…/… Italian guidelines: on the use of innovative materials for structural purposes in an appendix. FRP bars used as reinforcement in concrete structures shall undergo inspections to ensure a satisfactory level of both mechanical and physical properties. The following is required: • Factory Production Control (FPC) shall relate to the geometrical, mechanical (stiffness and strength) and physical properties of the FRP bars as discussed in the following sections; • the bar manufacturer shall use base materials (fibre and resin) certified by their supplier. bar mechanical properties are reported in Appendix C. Conclusions Through the technical documents described in this article, the Italian National Research Council has contributed to better knowledge of composite materials within the Italian professional community, to the definition of design principles and application rules accepted by the Italian scientific community and to the standardisation of test procedures for the mechanical characterisation of FRP materials. Contact: l.ascione@unisa.it More information: www.cnr.it All the documents are available for download on this web site. Fibre-reinforced concrete structures The document entitled “Guide for the Design and Construction of FibreReinforced Concrete Structures” deals with the structural use of fibrereinforced concrete (FRC). FRC is a concrete material incorporating short steel fibres and polymeric, inorganic (carbon or glass) or natural fibres. Adding fibres to concrete makes it significantly more resistant to traction after cracking. FRC applications of relevant interest include: load-bearing front panels, paving slabs, beams, structural joints and nodes, jacketing elements, structures subject to impacts and/or fatigue, railway sleepers, high tension poles, etc. (Figure 6). References [1] L. Ascione, A. Benedetti, R. Frassine, G. Manfredi, G. Monti, A. Nanni, C. Poggi, E. Sacco: “Design guidelines for the strengthening of existing structures with FRP in Italy”, International Conference FRPRCS7, New Orleans, 2005. [2] L. Ascione, L. Feo: “Design guidelines for the strengthening of reinforced concrete and masonry structures with FRP in Italy (CNR-DT 200/2004)”, International Conference on Composites Engineering (ICCE/12), Tenerife, Spain, 2005. [3] L. Feo: “Advanced composites as strengthening materials for civil constructions: state of the art and modern code developments in Italy”, International Conference on Composites Engineering (ICCE/14), Boulder, Colorado, USA, 2006 (keynote). [4] L. Ascione, A. Benedetti, A. Borri, A. Di Tommaso, L. Feo, R. Frassine, G. Manfredi, G. Monti, A., M., C. Poggi, E. Sacco: “Italian design guidelines for the strengthening of existing civil constructions using externally bonded fibre-reinforced polymers”, Third International Conference on FRP Composites in Civil Engineering (CICE 2006), December 13-15, 2006, Miami, Florida, USA. [5] L. Ascione, G. Manfredi, G. Monti, A. Nanni: “The new Italian design guidelines Fig. 5: Trout River Bridge, AICan Highway (British Columbia). Product sampling and testing of the product samples shall be carried out regularly in the manufacturing plant. Both mechanical and physical qualification tests shall be carried out by a certified laboratory provided with the necessary equipment and experience in the characterization of composite materials. If the factory laboratory is either not available or not certified, the qualification tests shall be carried out by an external laboratory certified in the characterisation of composite materials. The mechanical characteristics reported in the technical data sheets of the products shall be obtained through a statistical analysis, including the characteristic values, percentile, sample mean, sample standard deviations, confidence intervals, and the number of samples tested. Suitable partial factors of the semi-probabilistic method should be employed for the characteristic values evaluated. Test methods for characterising the FRP- Fig. 6: Oceanographic Museum (Valencia). The document deals with the following issues: • materials: fibres, matrices, fibre-reinforced concrete properties; • basic design concepts: safety factors, durability requirements; • ultimate limit state: one-dimensional and two-dimensional elements; • serviceability limit state: tension verification, crack opening; • execution: mixture composition, reinforcement positioning, minimum size, laying execution; • fire resistance; • testing and production control. The document also has five appendices devoted to several theoretical aspects that are briefly discussed in the instructions and, due to their innovative nature, merit further mention with an informative aim. JEC Composites Magazine / No34 July-August 2007

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JEC COMPOSITES MAGAZINE - Issue #35 - September 2007

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #35 - September 2007