Research and Innovation
ECS members develop products that are high in quality and added value for users. Coupled with reliable services, they facilitate modern alternatives to conventional construction techniques, increase safety in construction, and thus contribute to effective construction.
The ECS assumes the task of initiating and coordinating pre-competitive research projects. Here, practical implementation of the results is always the focus.
The main topics of research include:
FP7 – SAFECLADDING – 2012/2015
The research project SAFECLADDING is aimed to investigate the seismic behavior of precast structures with cladding wall panels and to develop innovative connection devices and novel design approaches for a correct conception and dimensioning of the fastening system to guarantee good seismic performance of the structure throughout its service life.
Occasion is the finding that the current design approach does not represent the real conduct in case of seismic impact. Several recent violent shakes showed dramatically, that the cladding panels, fixed to the structure, come to be integral part of the resisting system conditioning its seismic response. The high stiffness of this resisting system leads to forces much higher than those calculated from the frame model precast buildings are usually designed with. Therefore, the design of these connections cannot rely on the seismic reduction factor used for design of the bare structure. New technological solutions for connectors with proper design approaches are urgently required.
High demands are made of the connection between concrete and steel, both in its normal use and also in a load condition. Requirements therefore exist for the surface geometry to guarantee sufficient bond properties. Appropriate guidelines and minimum values for the ribbed surface concerned fR are specified in DIN 488. Alternatively to the guidelines, evidence based on the DIN EN 10080 (2005) using the RILEM stretch test and beam test is now possible.
In this case, no demands on the rib geometry are made, which could, however, under certain conditions lead to the rod in the component not always meeting the demands. In this research, the influence of the ribbed surface concerned, the bond behaviour and the principal suitability of the beam-end test for qualifying reinforcement rods will be investigated.
With introduction of the ten EUROCODES with the related national annex a fundamental milestone in the harmonization of European building codes for construction and design was reached. The Eurocorde 2 in connection with the national annex DIN EN 1992-1-1; NA: 2013-04/1.1/ for concrete, reinforced concrete and prestressed concrete replaced the national building codes DIN 1045-1:2008-08, DIN-Fachbericht 102/1.3/ and DIN 4102/1.4/ (in parts).
The ECS assigned in cooperation with the ISB and the DAfStb a group of authors to give detailed advices for on one hand normative and on the other hand economic reasonable reinforcement. This advices were combined in the DAfStb-Heft 599 “Bewehren nach Eurocode 2” which will give the engineer and the draftsmen a basic tool representing the state of the art in quality of reinforcement in all relevant points.
The use of concrete reinforcement rods with a large diameter > 32 mm can make sense from a practical building perspective for several reasons. With heavily reinforced designs, such as foundation slabs and supporting pillars subject to high loads, significant simplifications in the configuration of the reinforcement can be achieved. The use of larger rod diameters reduces the number of reinforcement layers and with it the work involved for positioning, increases the static effective height and simplifies concreting due to the larger spacing of the rods.
To advance the clarification of open questions on reinforcement configuration, the ECS supports the “Advancement of measurement and design rules for large rod diameters (> 32 mm, BSt500)” project. Contributing research locations are the technical universities RWTH Aachen, TU Braunschweig and TU Kaiserslautern.
The innovative contribution of the research project consists primarily of the extension of existing dimensioning approaches and design rules to larger rod diameters, which contributes significantly to the cost effectiveness and continued development of the reinforced concrete construction method.
Here you’ll find the first final report.