Walter Kaufmann


Last Name

Kaufmann

First Name

Walter

ORCID

0000-0002-8415-4896

Organisational unit

09469 - Kaufmann, Walter / Kaufmann, Walter

Search Results

Publications1 - 10 of 195
  • Determination of the effective concrete area in tension relevant for modelling tension stiffening in SLS and ULS design
    Item type: Conference Paper
    Galkovski, Tena; Mata Falcón, Jaime; Kaufmann, Walter (2021)
    fib Symposium Proceedings ~ Concrete Structures: New Trends for Eco-Efficiency and Performance, Proceedings of the fib Symposium 2021
  • Puente Basculante Porta d' Europa en el Puerto de Barcelona
    Item type: Other Conference Item
    Arenas, Juan J.; Kaufmann, Walter (2001)
  • Flächentragwerke: 20-148
    Item type: Educational Material
    Kaufmann, Walter (1998)
  • Bottle-shaped stress field solution for partially loaded reinforced concrete blocks
    Item type: Conference Paper
    Markic, Tomislav; Kaufmann, Walter (2018)
    Proceedings of the 12th fib International PhD Symposium in Civil Engineering
    Most existing approaches for the design of partially loaded areas in reinforced concrete – including design rules in international codes – are purely empirical, and based on experimental tests on unrein-forced concrete. In this paper, a bottle-shaped stress field solution for strip loading is presented and generalised for axisymmetric cases of partial area loading. The model is compared to experimental results as well as predictions obtained from existing models and design rules. While the correlation with the available experimental evidence is good, further experiments are required for verification, particularly for the case of heavily confined areas.
  • Modeling locally corroded reinforced concrete structures in non-linear finite element analyses
    Item type: Journal Article
    Reckinger, Nathalie; Haefliger, Severin; Thoma, Karel; et al. (2025)
    Structural Concrete
    The ingress of chlorides, originating from the use of de-icing salts or proximity to the sea, may cause severe local reinforcement corrosion in concrete structures such as bridges, tunnels, galleries, and retaining walls. Methods are urgently required to realistically assess the load-bearing capacity of such deteriorated structures, accounting for the effects of the local damage. However, modeling local corrosion in concrete structures using the finite element method is not straightforward. On the one hand, analyzing the local effects of corrosion requires finite elements that are magnitudes smaller than appropriate element sizes used to efficiently model an entire concrete structure, making this approach unviable even when using high-performance computers. On the other hand, when modeling a structure with comparingly large elements, local damage introduces a discontinuity in the affected FE, which are thus no longer a continuum as presumed in standard element formulations. Hence, the influence of the discontinuities needs to be captured consistently and independently of the element size. This paper presents a mechanically consistent approach to deal with discontinuities by defining an influence volume and a correspondingly aligned constitutive relationship. The approach is demonstrated using the existing Corroded Tension Chord Model as a constitutive relationship and validated against the analytical solution for a reinforced concrete tie affected by local corrosion and three experiments on continuous slab strips with and without local damage. The load-deformation behavior of the reinforced concrete tie is accurately captured by the numerical simulation. The load-deflection behavior and failure modes observed in the experiments can be accurately predicted without mesh size dependency, thus proving the suitability of the proposed approach.
  • Design, Construction and Capabilities of the Large Universal Shell Element Tester
    Item type: Conference Paper
    Kaufmann, Walter; Beck, Alexander; Karagiannis, Dimosthenis; et al. (2022)
    The Large Universal Shell Element Tester (LUSET) is a new testing facility that has been developed at ETH Zurich. It enables the investigation of the load-deformation behaviour of full-scale reinforced concrete shell elements under arbitrary loading conditions. The motivation for the development of the LUSET is outlined followed by a description of the hardware and software components of the setup and the measurement systems used. Finally, the test series for validating the functionality of the LUSET is discussed and a general overview of the facility’s overall testing capabilities is given.
  • Ausziehversuche randnaher Bewehrung
    Item type: Report
    Kaufmann, Walter; Galkovski, Tena (2019)
    Der vorliegende Bericht dokumentiert die Vorbereitungen, die Durchführung sowie die Auswertung von Ausziehversuchen an randnahen, einbetonierten und nachträglich installierten Bewehrungsstäben. Die Versuche wurden in Anlehnung an den Versuch AC308 (acceptance criteria for adhesive anchor systems in concrete elements, gemäss acceptance criteria for post- installed adhesive anchors in conrete elements der ICC-ES, 2013) durchgeführt, womit ein Spaltversagen des Betons angestrebt wird. Prüfparameter waren die Lage der Stäbe beim Betonieren (Unterseite oder Oberseite) und die Art des Verbundes (einbetoniert oder nachträglich installiert, mit vier unterschiedlichen Hilti Verbundmitteln). Die Einbindelänge, die Betonsorte sowie der Stabdurchmesser wurden nicht variiert. Es wurden acht prismatische Versuchskörper mit jeweils vier in den Ecken angeordneten Bewehrungsstäbe verwendet, wobei die Stäbe in einer Diagonale jeweils gleich ausgeführt wurden: einbetoniert oder nachträglich installiert. Somit lagen beim Betonieren pro Prüfkörper jeweils ein einbetonierter und ein nachträglich installierter Stab auf der Unterseite (geschalte Fläche) und auf der Oberseite (ungeschalte Fläche). Als Messsysteme wurden Digitale Bildkorrelation (DIC, engl. Digital Image Correlation) für die Deformationen an der Betonoberfläche entlang der Einbindelänge und kontinuierliche faseroptische Dehnungsmessungen an den Bewehrungsstäben eingesetzt (FO, engl. Fibre Optics). Diese Messsysteme ermöglichen einen vertieften Einblick in das Verhalten, insbesondere bezüglich der Interaktion zwischen Beton und Bewehrungsstahl (Verbund).
  • Mesh Mould: An On Site, Robotically Fabricated, Functional Formwork
    Item type: Conference Paper
    Hack, Norman; Wangler, Timothy; Mata Falcón, Jaime; et al. (2017)
  • Experiments on locally corroded retaining wall segments and their assessment with the Corroded Tension Chord Model
    Item type: Conference Paper
    Häfliger, Severin; Kaufmann, Walter (2021)
    Capacity Assessment of Corroded Reinforced Concrete Structures CACRCS (2020) Proceedings
    Localised corrosion reduces the strength and, even more pronouncedly, the deformation capacity of reinforced concrete structures. These effects are particularly critical in hyperstatic systems and structures subjected to deformation dependent loading, as they may cause premature brittle failures limiting moment redistribution and load reduction, respectively. This paper presents the results of eight largescale experiments investigating the load-deformation behaviour of retaining wall segments with varying localised corrosion damage. The experiments included two hybrid tests exploring the interaction of deformation capacity and deformation dependent load. The Corroded Tension Chord Model was used to model the structural behaviour, revealing excellent agreement with the experimental data.
  • Structural Concrete Design in the 21st Century: are Limit Analysis Methods obsolete?
    Item type: Conference Paper
    Kaufmann, Walter; Mata Falcón, Jaime (2017)
Publications1 - 10 of 195