Technical Committee 232-TDT
Activity ending in: 2014
Textile reinforced concrete is a new composite material which has been developed in the last 10 years. Especially in Germany two collaborative research centres exist (Aachen and Dresden) which very basically investigated the composite in respect to new building members (e. g. façade elements, integrated formworks, sandwich walls and ceilings, frameworks, shells) and maintenance of existing structures (strengthening and sealing). The composite is a very sustainable material due to the minimum thickness of at least 10 mm.
The proposed committee is a direct follow-up of the successful committee TC 201-TRC, which in 2006 organized an international conference in Aachen, Germany, and beside the proceedings of the conference (PRO 50) worked out a state-of-the-art-report (REP 32), so 700 pages of high quality have been produced in order to make the material more public for application. TC 201-TRC has started to work out recommendations for testing the yarns, textiles, pull-out behaviour and the composite itself. Due to the restrictions of the duration of committee lives it has been decided to close the old committee and directly propose a follow-up.
One major item is the cooperation with ACI 549 – Thin concrete elements, where similar topics are dealed with.
The proposed TC will continue the work in recommendations of test methods and work out a manual for design of the composite. At least, the state-of-the-art-report will be updated at the end of the committee work, including the recommendations and manual
Terms of reference
The recommendations will be finished within 3 years. The manual of design should be worked out after 4 years. The update of the SAR should be ready after 5 years. About 20 members - also involved in the former committee - will actively participate. For the SAR there might be some more helping, as it has been carried out with REP 32.
Concerning the recommendation it is planned to carry out round robin tests - some on the composite are finished.
The TC will have it’s next (first) meeting within the RILEM week in Haifa 2009-09-07/11, has organized a slot of contributions in combination with ACI 549 in spring 2010-03-21/25 in Chicago, also having a meeting there, and will organize the 2. international symposium on TRC in Aachen within the RILEM week 2010-09-06/10, again having a meeting there. So until end of 2010 the timetable is complete.
Detailed working programme
1. Recommendations for testing methods for:
- yarn/roving mechanical properties in tension
- pull-out behaviour of yarns/rovings
- tensile behaviour of the composite material
2. Design manual
In comparison to conventional design methods of steel reinforced concrete the load cases tension, shear and bending will be described and formulas for design will be given for structural engineers.
The existing RILEM report 32 will be updated taking into account the new state of the art. Also the recommendations and the design manual will be included.
TRC is a new composite material, covering all aspects of material science, from durability, mechanical behaviour, fracture mechanics, design methods to applications. Each item by itself directly fits to the RILEM philosophy. The first TC on TRC was quite successful, but due to the wide range of items not able to finish the work. Therefore it is strongly recommended by all the members of the old committee to continue the work.
Direct benefits will be standardized test methods for the composite, so experimental data will be comparable - up to now they are not always. A design manual will lead to more application - up to now one has to find experts also for a pre-design, which one cannot handle in practice. The update of the SAR will show more applications and therefore is essential for a wider practical use.
The 2nd international conference on TRC sponsored by the German Research Foundation and RILEM will be held September 2010 in Aachen.
Group of users
There will be a scientific exchange within the work of the committee, but at least the aim is to open the new composite material to the practical application. So it is useful for the textile industry as well as the producers of precast elements, but also the common building industry. Examples for application are important to show the architects the possibilities of this innovative material.
Specific use of the results
The recommendations of test methods should serve as basis for international standards. They avoid double research in finding test methods, because the testing of composite materials with multifilament yarns is very complicated and needs restrictions in the boundary conditions.
The design manual will be a tool people may use for checking the possibility of application of TRC in the projecting phase. Decisions therefore are highly supporting the idea of TRC.
The SAR will show the basics of TRC as well as the very different applications by examples and therefore motivate architects and engineers for using TRC. The report will be again a very good example for the publication policy of RILEM.