The overall motivation of fib Commission 4 (COM4) is to make theoretical and practical developments in the field of concrete and concrete technology, and to present these developments in an understandable and code-type formulated manner. COM4 positions itself at the forefront of new technologies and techniques by considering both fundamental research and practical issues.
Scope and objective of technical work
The aim of COM4 is to collect and to validate information on the properties and behaviour of concrete for structural applications subjected to various types of loading and environmental conditions. The commission focuses its attention both on traditional types of concrete, in particular under unusual conditions, and on new types of concrete and cementitious composites under all types of loading and condition. The properties of the concrete types considered should be formulated in such a way that it is possible to derive behavioural models and design recommendations for practical applications.
|First name||Last name||Country||Affiliation|
|Frank||Dehn||Germany||KIT Karlsruher Institut für Technologie|
|Liberato||Ferrara||Italy||Politecnico di Milano|
|Harald||Justnes||Norway||SINTEF Building and Infrastructure|
|Steinar||Helland||Norway||S Helland Konsult|
|Joost||Walraven||Netherlands||Delft University of Technology|
|Mette||Geiker||Norway||NTNU - Trondheim Norwegian Univ.|
|Viktor||Mechtcherine||Germany||Technical Univ. Dresden|
|Hans-Dieter||Beushausen||South Africa||University of Cape Town|
|Harald||Müller||Germany||SMP Ingenieure im Bauwesen GmbH|
|Steffen||Grünewald||Netherlands||Sustainable Concrete Centre|
|Geert||de Schutter||Belgium||Ghent University|
|Ludger||Lohaus||Germany||Leibniz Universität Hannover|
|Jean Michel||Torrenti||France||Univ Gustave Eiffel|
|Michael||Haist||Germany||Leibniz Universität Hannover(KIT)|
|Nikola||Tošić||Spain||Universitat Politècnica de Catalunya|
|Martin||Cyr||France||Université de Toulouse|
- TG4.1 - Fibre-reinforced concrete
- TG4.2 - Ultra high-performance fibre-reinforced concrete
- TG4.3 - Structural design with flowable concrete
- TG4.4 - Aesthetics of concrete surfaces
- TG4.5 - Time-dependent Behavior of Concrete
- TG4.6 - Constitutive laws for concretes with supplementary cementitious materials
- TG4.7 - Structural Applications of Recycled Aggregate Concrete – Properties, Modeling, and Design
- TG4.8 - Low-carbon concrete structures
TG4.1 - Fibre-reinforced concrete
Fibre concrete is more than 50 years old and the design rules have undergone developments over the years. TG4.1 will make theoretical and practical developments in the field of fibre-reinforced concrete materials technology, rheology and materials characterisation and modelling and to present these developments in code-type formulations.
The task group collects and validates information on the behaviour of fibre-reinforced concrete materials, subjected to various types of loading and environmental conditions.
TG4.1 is currently finalising a bulletin on the background to the design rules in MC2010.
First name Last name Country Affiliation Lucie Vandewalle Belgium KULeuven David Fernández-Ordóñez Switzerland fib Frank Dehn Germany KIT Karlsruher Institut für Technologie Pierre Rossi France IFSTTAR Ravindra Gettu India Indian Institute of Technology Madras Barzin Mobasher United States Arizona State University Giovanni Plizzari Italy University of Brescia Joaquim A. O. Barros Portugal Universidade do Minho György L. Balázs Hungary Budapest Univ. of Techn. & Economics Marco di Prisco Italy Politecnico di Milano Avraham Dancygier Israel Technion-Israel Institute of Technology Gustavo Parra-Montesinos United States University of Michigan Ingemar Löfgren United Kingdom - Xavier Destree Belgium - Wolfgang Kusterle Germany OTH Regensburg Horst Falkner Germany Retired Nemkumar Banthia Canada Univ. of British Columbia Tim Soetens Belgium Sanacon Ulvis Skadiņš Latvia - Pavel Shandaliy Russian Federation MC-Bauchemie Russia Sherif Yehia United Arab Emirates - Peng Gao China Hefei University of Technology Dara McDonnell Australia Arup Klaus-Alexander Rieder United States GCP Applied Technologies Inc.
TG4.2 - Ultra high-performance fibre-reinforced concrete
Task Group 4.2 (TG4.2) will make theoretical and practical developments for concretes with strength > 120 N/mm2 in the field of fibre-reinforced concrete materials technology, rheology and materials characterisation and modelling to present these developments in code-type formulations. Work is applicable to concrete with fibres of various types, such as steel, polymeric or combinations thereof.
The work of TG4.2 is coordinated with the work of fib TG4.1 (Fibre-reinforced concrete) that develops recommendations for conventional fibre-reinforced concrete.
First name Last name Country Affiliation Frank Dehn Germany KIT Karlsruher Institut für Technologie Pietro Gambarova Italy Politecnico di Milano Mouloud Behloul France Lafarge Stefan Greiner Germany Bilfinger + Berger AG Alain Simon France Eiffage TP Kai Bunje Germany IBB Fehling & Jungmann GmbH Thierry Thibaux France Eiffage Makoto Katagiri Japan Taiheiyo Cement Corporation Jacques Resplendino France Setec TPI Marijan Skazlic Croatia University of Zagreb Torsten Leutbecher Germany Universität Siegen Berndt Aarup Denmark CRC Technology ApS Benjamin Graybeal United States PSI/FHWA Structures Pierre Marchand France IFSTTAR Björn Frettlöhr Germany - Joost Walraven Netherlands Delft University of Technology Ekkehard Fehling Germany IBB Fehling + Jungmann GmbH Pierre Rossi France IFSTTAR Dario Redaelli Switzerland School of Engineering and Architecture - Fribourg David Fernández-Ordóñez Switzerland fib Emmanuel Denarie Switzerland EPF Lausanne Steffen Grünewald Netherlands Sustainable Concrete Centre Nguyen Viet Tue Austria Technische Universität Graz Yasuhiko Sato Japan Waseda University Karl-Heinz Reineck Germany - Michael Schmidt Germany Fehling + Jungmann GmbH François Toutlemonde France IFSTTAR Marco di Prisco Italy Politecnico di Milano
TG4.3 - Structural design with flowable concrete
Flowable concrete (highly flowable, self-compacting and/or self-levelling) has evolved from a special type to a commonly applied building material. fib Task Group 4.3 (TG4.3) considers three aspects of flowable concrete (FC) for structural design: material properties, production effects and structural boundary conditions. The flow of concrete (initiated by some vibration and/or the weight of concrete) can affect the structural characteristics of hardening or hardened concrete. The mixture composition has to be adjusted and optimised in order to obtain a high flowability. TG4.3 aims at promoting the application of flowable concrete, improving and adapting the concrete design and the production technology and its implementation in guidelines and codes.
First name Last name Country Affiliation Frank Dehn Germany KIT Karlsruher Institut für Technologie Liberato Ferrara Italy Politecnico di Milano Mouloud Behloul France Lafarge Ravindra Gettu India Indian Institute of Technology Madras Bas Obladen Netherlands Strukton Group Peter Billberg Sweden Strängbetong Laetitia Martinie France INSA Nicolas Roussel France IFSTTAR Bernhard Freytag Austria Technische Universität Graz Mohamed Sonebi Ireland Queen’s University Belfast Patrick Stähli Switzerland Concretum Construction Science AG Filipe Laranjeira Spain Univ. Politecnica de Catalunya Guido Bertram Germany Grawe + Bertram Ingenieure Andreas Leemann Switzerland EMPA Susan Taylor Ireland Queen's University Belfast Sandra Nunes Portugal University of Porto On Spangenberg Denmark Technical University of Denmark Gregor Fischer Denmark Technical University of Denmark Joost Walraven Netherlands Delft University of Technology Mette Geiker Norway NTNU - Trondheim Norwegian Univ. Terje Kanstad Norway The Norwegian Univ.of Science & Tech Henrik Stang Denmark University of Denmark Konrad Zilch Germany - Steffen Grünewald Netherlands Sustainable Concrete Centre Wolfram Schmidt Germany BAM - Bundesanstalt für - Materialforschung und -prüfung John Cairns United Kingdom Heriot-Watt University David Fernández-Ordóñez Switzerland fib Bryan Barragan France OCV Chambery International Joop Den Uijl Netherlands - Harald Beitzel Germany Inst. für Bauverfahrens- und Umwelttechnik Yasuhiko Sato Japan Waseda University Lucie Vandewalle Belgium KULeuven Joaquim A. O. Barros Portugal Universidade do Minho Marco di Prisco Italy Politecnico di Milano Tor Martius-Hammer Norway SINTEF AS
TG4.4 - Aesthetics of concrete surfaces
The notion of exposed concrete is subjective and varies according to the viewer. The motivation of fib Task Group 4.4 (TG4.4) is to show possibilities how to categorise and evaluate visible concrete surfaces and how to point out technical factors of influence.
TG4.4 will formulate a state-of-the-art technical report on how exposed concrete is defined and built. The final aim is to create a generally accepted recommendation or guidelines for exposed concrete with a homogenous appearance. This generally accepted recommendation or guidelines will be characterised by classifying exposed concrete in different categories. The limit of its objective performance will be considered as well as the consequences on the effort on-site and the planning of structural framework.
First name Last name Country Affiliation Frank Dehn Germany KIT Karlsruher Institut für Technologie Tone Anita Østnor Norway SINTEF Building and Infrastructure Lluis Casals Roige Spain Oficina tecnica d’enginyeria civil Klaus-R. Goldammer Germany Deutscher Beton- und Bautechnik-Verein e.V. Christoph Motzko Germany TU Darmstadt Alexander Reinisch Austria Doka Industrie GmbH Erik Boska Germany TU Darmstadt Antonia Pacios Alvarez Spain ETS Ingenieros Industriales - UPM Klaartje de Weerdt Norway NTNU Christian Hofstadler Austria Institut für Baubetrieb und Bauwirtschaft Karen Fischer Germany Leibniz Universität Hannover Nikki Cauberg Belgium WTCB-CSTC-BBRI Elisabeth Hierlein Germany FDB - Fachvereinigung Ludger Lohaus Germany Leibniz Universität Hannover David Fernández-Ordóñez Switzerland fib Bryan Barragan France OCV Chambery International Maher Tadros United States University of Nebraska-Lincoln Morten Gjerde New Zealand Victoria University of Wellington
TG4.5 - Time-dependent Behavior of Concrete
The primary objective of the task group is to identify limiting aspects during the design of new or assessment of existing structures related to predicting the time-dependent (mechanical) behavior of “new” but also “traditional” concrete types. Based on the identified short-comings the task group will initiate literature reviews, compile/ update consistent databases and update existing model formulations. Where possible the TG will make use of the data already available in the scientific literature. Where this is not the case, the task group will strive to develop research strategies and coordinate research efforts by its members, supported by national or international research funds.
The task group plans to develop databases and calibrated prediction models for the time-dependent mechanical properties of cast concrete including:
- Maturity vs. time concepts, applicable to early age and multi-decade predictions
- Development of compressive and tensile strength as function of maturity/ time;
- Development of Young’s modulus as function of maturity/ time;
- Development of fracture energy as function of maturity/ time;
- Development of creep and shrinkage as function of maturity/ time;
- Empirical relationship between mechanical properties and compressive strength as function of maturity/ time;
- Development of stress-strain diagram as function of maturity/ time;
- Transport of liquids and gases;
- Guidance for the coupled hygro-thermal chemo-mechanical analysis of concrete with relevance to e.g. mass concrete or certain structural components prone to early-age cracking;
- Guidance for the time-dependent nonlinear (fracture mechanical) analysis of concrete including advanced constitutive models and strain rate effects;
- Time-dependent resistance of concrete subject to sustained load
- Time-dependent resistance of concrete subject to fatigue;
First name Last name Country Affiliation Frank Dehn Germany KIT Karlsruher Institut für Technologie Robert Coufal Czech Republic TBG METROSTAV s.r.o. Annemarie Herrmann Germany - Joachim Juhart Austria Graz University of Technology Véronique Baroghel-Bouny France - Gert König Germany König und Heunisch Planungsgesellschaft Frank Altmann Qatar BG&E Sonja Fennis Netherlands Rijkswaterstaat Grote Projecten & Onderhoud Mark Alexander South Africa University of Cape Town Nele De Belie Belgium - Franka Tauscher Germany - Guang Ye Netherlands Delft University of Technology Doug Hooton Canada University of Toronto Joost Gulikers Netherlands Rijkswaterstaat Centre for Infrastructure Mette Geiker Norway NTNU - Trondheim Norwegian Univ. Viktor Mechtcherine Germany Technical Univ. Dresden Alfred Strauss Austria Univ. Bodenkultur Vienna Roberto Torrent Switzerland Quali- Ti-Mat Sagl Steffen Grünewald Netherlands Sustainable Concrete Centre Michael Haist Germany Leibniz Universität Hannover(KIT) David Fernández-Ordóñez Switzerland fib Hans-Dieter Beushausen South Africa University of Cape Town Roman Wan-Wendner Belgium Ghent University Harald Müller Germany SMP Ingenieure im Bauwesen GmbH Geert de Schutter Belgium Ghent University Dara McDonnell Australia Arup
TG4.6 - Constitutive laws for concretes with supplementary cementitious materials
The use of Supplementary Cementitious Materials (SCM) as binder in concrete is increasing, mainly driven by the need of the concrete industry to make concrete more environmentally friendly and in particular to meet official requirements for lower CO2 emissions. Here, it is to replace considerable amount of the high emitting Portland cement with low emitting SCM. The fib Model Code for Concrete Structures 2010 (MC2010) covers the use of SCM, but limits the materials and the amount of SCM. The overall motive of fib Task Group 4.6 (TG4.6) is to prepare the basis for an extension of the MC2010 that includes assessment of less known SCM as well as larger replacements.
TG4.6 aims to prepare a state-of-the-art report addressing the items in chapter 5.1 Materials – Concrete in the MC2010. The constitutive relations can be formulated as in, and assessed in relation to compliance with those given in MC2010.
First name Last name Country Affiliation Frank Dehn Germany KIT Karlsruher Institut für Technologie Guang Ye Netherlands Delft University of Technology Doug Hooton Canada University of Toronto Björn Lagerblad Sweden CBI Jeanette Visser Netherlands Strukton Engineering Thomas Bier Germany TU Bergakademie Freiberg Steinar Helland Norway S Helland Konsult Carmen Andrade Spain Centre Internacional de Mètodes Numèrics en l’Ènginyeria (CIMNE) Claus Pade Denmark Danish Technological Institute Anya Vollpracht Germany Private David Fernández-Ordóñez Switzerland fib Emmanuel Denarie Switzerland EPF Lausanne Geert de Schutter Belgium Ghent University Fragkoulis Kanavaris United Kingdom Arup
TG4.7 - Structural Applications of Recycled Aggregate Concrete – Properties, Modeling, and Design
The main objective of the TG is to formulate design recommendations for the structural use of RAC. This will take the form of proposing new or adjusting existing expressions and models for mechanical and structural properties of reinforced and prestressed concrete structures.
To achieve this goal, the TG will first perform a comprehensive critical review of literature alongside a preparation of databases of experimental results regarding mechanical and structural properties of RAC. Where necessary and possible, identified gaps in existing results will be complemented by new studies of TG members within existing or new research projects. Based on this work, the TG will formulate expressions and models for the following:
- Physical properties of RAC – density, water absorption, permeability
- Mechanical properties – compressive strength, tensile strength, modulus of elasticity, stress–strain relationship, fracture energy, shrinkage, creep
- Durability-related properties – carbonation resistance, chloride ingress, freeze-thaw resistance, chemical attack
- Structural behavior – flexural strength, shear strength, axial strength, punching strength, seismic resistance, fire resistance, deformation, cracking, bond and anchorage
- Fire resistance of RAC and RAC structures – resistance under fire and residual resistance after exposure to elevated temperatures of RAC and reinforced and prestressed RAC members
First name Last name Country Affiliation Nikola Tošić Spain Universitat Politècnica de Catalunya Jean Michel Torrenti France Univ Gustave Eiffel David Fernández-Ordóñez Switzerland fib
TG4.8 - Low-carbon concrete structures
Decreasing the environmental impact of concrete structures is an objective put forward by almost all the actors involved in the domain of construction. Although cementitious materials intrinsically involve low embodied energy, their use in large volumes in worldwide construction lead to approximately 8% of global CO2 emissions. Portland cement is the main constituent responsible for the environmental impacts caused by the life cycle of concrete, as it generates on average more than 800 kg CO2/t of clinker.
The task group will have two main objectives:
1- Identify the different ways to obtain low-CO2 concretes among the different possible routes:
- Evaluate which ones are rapidly reachable and how far we are from an universal utilization of these concretes.
- Define the work to carry out to bring these concrete at an industrial level.
- Estimate the scientific, technical and economical obstacles and challenges that could retard the implementation and acceptances of such concretes.
2- Evaluate the consequences of these low-CO2 concretes on the design of concrete structures, in terms of:
- Durability, for instance the impact of these new concretes on carbonation and chloride ingress, the most widespread problems facing reinforced concrete worldwide.
- Structural design, with the verification of the applicability of the international codes (Eurocodes…). The part concerning creep and shrinkage will be developed in the new COM4/TG Time dependent behavior of concrete.
First name Last name Country Affiliation Martin Cyr France Université de Toulouse David Fernández-Ordóñez Switzerland fib