Structure-WP - Top-Crete

Stucture -Work Packages

The following scheme summarizes the research methodology, approach and logical sequence of the TOP-Crete project. It highlights that the 3-year project consists of Applied/Industrial Research activities structured into 6 research Work Packages (WPs).

WP1 TP rebar composition and production

WP1 has the aim of developing TP glass fibre reinforced polymer (GFRP) rebars focusing on subsequent recycling steps for use in concrete reinforcement. In that framework the thermoplastic resin Elium® will be optimized to meet all required specifications in terms of processability by pultrusion and performance in the composite for being applied in concrete reinforcement (WP2 and WP3). Furthermore, the resin is to be further developed for subsequent recycling steps addressed in WP4.

Responsible: Sireg Participants: UPC, Hormipresa, Canoe, Arkema, OHLA, BUT

WP2 Short and long-term properties and bond behavior of TP FRP rebars

WP2 focuses on the performance of newly developed TP FRP rebars. Both short-term characteristics and long-term behaviour caused by creep and aggressive environment will be experimentally determined. Furthermore, rebars will be tested under extreme conditions, more precisely under fatigue loading and elevated temperatures corresponding to fire accidents. Besides tensile properties of the TP FRP rebars, experimental investigation will be also focused on bond between TP FRP and concrete and degradation caused by above mentioned extreme loading conditions.

Responsible: BUT Participants: UPC, Hormipresa, Canoe, Arkema, OHLA, Sireg

WP3 Short and long-term performance of RC elements with TP FRP rebar

WP3 is dedicated to the performance of concrete elements reinforced with bendable TP FRP rebars. Full-scale short-term tests will be developed to assess the flexural and shear capacity of RC beams with longitudinal TP FRP rebar with and w/o bent TP FRP transverse reinforcement. In addition, long-term tests on full-scale beams under sustained load will be performed to study the time-dependent behaviour of elements with TP FRP rebars.

Responsible: UPC Participants: Hormipresa, Canoe, Arkema, OHLA, BUT, Sireg

WP4 Sustainability based assessment and optimization of TP FRP rebar

WP4 focuses on the sustainability of concrete structures reinforced with high-performance composite rebars. In a first step, recyclability of TP FRP rebars will be studied by shredding-grinding and introduction into the thermoplastic resin. Formulations will be developed following a compatibilization approach between the matrix and recycled materials, made easier by this new generation of TP manufactured rebars. Granulometry and additives will be evaluated to observe impacts on formulations. Compounding facility such as twin-screw extrusion and injection moulding will be used. These new processed thermoplastic composites, elaborated with a percent of recycled FRP, will be characterized (rheology, mechanical properties…) and compared with equivalent commercial products. In a second step, TP FRP rebars will be removed from RC elements, and they will be reused in demonstrators of new recycled thermoplastic injected elements for the construction sector, such as reinforcement spacers. The impact of a low ratio of concrete dust in the recycled resin will be tested in order to evaluate cohesion between TP resin and recycled materials.

Responsible: Canoe Participants: UPC, Hormipresa, Arkema, OHLA, BUT, Sireg

WP5 Structural application demonstration

WP5 deals with the structural application in a prototype of the newly developed reinforcement. Its main aim is to validate practical application of TP FRP rebars in full-scale real concrete members. This validation includes design, numerical analysis, production, experimental evaluation of the behaviour of concrete members in conditions corresponding to real environment in desired application field. Two different real environments will be considered (Czechia and Spain). Finally, a sustainability-based assessment (economic enviromental and social aspects in the Life Cycle Impact Assessment) of the prototypes will be performed to quantify their potential benefits over traditional steel bar-reinforced solution.

Responsible: OHLA Participants: UPC, Hormipresa, Canoe, Arkema, BUT, Sireg

WP6 Design guidelines for TP FRP RC elements

The results of the experimental programs developed in WP2, WP3 and WP5 will be used to develop analytical models for the short and long-term behaviour of RC elements with TP FRP rebars, such as the multi-action shear model, previously developed by UPC, which will be extended for RC elements with embedded TP FRP reinforcement to assess their shear strength. These models will lead to the development of design recommendations that will be formulated to facilitate their future incorporation in codes such as Eurocode 2 and the fib Model Code. Finally, knowledge accumulated in WP2 will be used to extend the analytical model to include selected extreme conditions, thus leading to comprehensive design solutions for RC members with embedded TP FRP reinforcement.