TY - CONF A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph ED - Rogge, Andreas ED - Meng, Birgit T1 - Beitrag zur Beurteilung der Wiederholbarkeit additiv gedruckter Betonbauteile N2 - Die additive Fertigung von Betonbauteilen, auch bekannt als 3D-Betondruck, ist eine Technologie, die im letzten Jahrzehnt aufgrund ihrer finanziellen und ökologischen Vorteile als nachhaltige Fertigungstechnologie viel Aufmerksamkeit erhalten hat. Obwohl die Vorteile der additiven Fertigung bereits durch zahlreiche Forschungs- und Demonstrationsprojekte gezeigt wurden, ist die Qualitätskontrolle während des Druckens äußerst anspruchsvoll und wird auch aufgrund fehlender harmonisierter Normen kaum angewendet. Aufgrund des kontinuierlichen Mischprozesses beim 3D-Betondruck ist es unmöglich Schwankungen des Trockenmörtels oder des Wassergehalts auszuschließen. Daher ist eine einzelne Stichprobe nicht mehr repräsentativ für das gesamte Bauteil und ein während des Druckens in einer Schicht auftretender Fehler kann die Integrität der gesamten Struktur beeinträchtigen. In diesem Beitrag werden die Ergebnisse eines als Fachwerkstruktur konzipierten Bogens, der unter vergleichbaren Randbedingungen mehrmals mit einem 3D-Betonextrusionsdrucker gedruckt wurde, vorgestellt. Jeder Bogen wurde auf seine mechanische Festigkeit und sein Tragverhalten geprüft. Die Ergebnisse der mechanischen Prüfungen der gedruckten Bögen werden mit Materialdaten aus klassischen Materialprüfungen verglichen und hinsichtlich ihrer statistischen Signifikanz diskutiert. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additiv gedrucktes Betonbauteil KW - Beurteilung KW - Wiederholbarkeit PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613043 SN - 978-3-9818564-7-7 SP - 126 EP - 131 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61304 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph T1 - An assessment of the repeatability of 3D printed concrete structures N2 - Additive manufacturing of concrete structures, also known as 3D concrete printing, is a technology that received a lot of attention over the past decade due to its financial an ecological advantage as sustainable construction technology. Although several techniques and approaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied and harmonized standards are not existing. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to be representative for the whole structure. A defect in one layer during the printing can affect the entire integrity of the whole structure. This study shows the results of an arch designed as framework structure that was printed multiple times under the same boundary conditions using an extrusion-based 3D concrete printer. Each arch was tested for its mechanical strength and load bearing behavior. The results of the mechanical testing of the printed arches are compared with material data obtained by classical tests and discussed regarding their statistical significance. T2 - Digital Concrete 2024 CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Repeatability KW - Monitoring KW - Process control KW - Quality control PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611012 DO - https://doi.org/10.24355/dbbs.084-202408150641-0 SP - 1 EP - 9 PB - TU Braunschweig AN - OPUS4-61101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüsken, Götz A1 - Strangfeld, Christoph A1 - Robens-Radermacher, Annika A1 - von Werder, Julia A1 - Weigel, Sandra A1 - Mezhov, Alexander T1 - 63. DAfStb-Forschungskolloquium in der BAM - Themenblock 3: Innovative Technologien N2 - Innovationen sind der Treiber des technologischen Fortschritts. Durch die Anwendung innovativer Technologien, Produktionsverfahren und neuer Materialien können Effizienzsteigerungen erzielt werden, die sowohl zu einer Kosten- als auch Materialreduzierung führen können. Gerade vor dem Hintergrund einer nachhaltigen Entwicklung sind Innovationen der Schlüssel zu einem verantwortungsvollen Umgang mit Ressourcen und Rohstoffen. Im Rahmen des 63. DAfStb-Forschungskolloquiums (Tagungsband: DOI 10.26272/opus4-61338) an der BAM wurden innovative Ansätze im Bereich effizienter Fertigungstechnologien und neuer Materialien vorgestellt, die nachfolgend kurz zusammengefasst werden. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - Additive Fertigung KW - Biorezeptive Oberflächen KW - Biopolymere PY - 2025 SN - 0005-9846 VL - 75 IS - 4 SP - 134 EP - 135 PB - concrete content UG CY - Schermbeck AN - OPUS4-63069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Correlation of continuously measured in-line process parameters and extruded geometry in 3D concrete printing experiments N2 - Additive manufacturing of concrete structures is a novel and emerging tech-nology. Free contouring in civil engineering, which allows for entirely new designs, is a significant advantage. Although several techniques and ap-proaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to represent the whole structure. A defect in one layer during printing can affect the in-tegrity of the entire structure. Therefore, continuous and real-time process monitoring is required to record and document the printing process. At the Bundesanstalt für Materialforschung und -prüfung (BAM), a test rig for 3D concrete printing was developed to monitor the properties during the printing process. This study investigates the relationship between geometric accuracy and process parameters (pressure, pump torque, print speed, layer height, water content) in extrusion-based 3D concrete printing. Using a high-precision laser scanner, the geometric measurements of printed concrete ele-ments are evaluated in real-time. The concrete elements are printed under controlled conditions with varied process parameters. Preliminary findings indicate a significant correlation between process variables and geometric ac-curacy. T2 - Fourth RILEM International Conference on Concrete and Digital Fabrication CY - Munich, Germany DA - 04.09.2024 KW - 3D concrete printing KW - Geometric accuracy KW - Process monitoring KW - Quality control PY - 2024 DO - https://doi.org/10.1007/978-3-031-70031-6_15 SP - 127 EP - 133 AN - OPUS4-61534 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jeyifous, Olubunmi Anthony A1 - Schönsee, Eric A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Investigating the impact of material rheology on geometric accuracy in 3D concrete printing using real-time monitoring N2 - Additive manufacturing of concrete structures is an innovative and rapidly advancing technology. One of its key advantages is the ability to achieve freeform designs in civil engineering, enabling entirely new architectural possibilities. However, despite the demonstrated benefits of this technology, maintaining consistent print quality during the printing process remains a significant challenge and is seldom implemented. The continuous mixing process inherent in 3D concrete printing introduces potential variations in the dry mix composition or water content, making a single test sample insufficient to represent the entire structure. Moreover, defects in a single layer can compromise the integrity of the whole structure. This underscores the need for continuous, real-time monitoring to document and ensure the quality of the printing process. At the Bundesanstalt für Materialforschung und prüfung (BAM), a 3D concrete printer was developed to enable real-time non-destructive monitoring of material properties during the printing process. This study examines the impact of rheological variations, influenced by water content variations, on the geometric characteristics of printed elements. Geometric measurements are captured in real time using a high-precision laser scanner. Concrete elements are printed under controlled conditions with systematically varied process parameters. Preliminary results reveal a strong correlation between rheological behaviour and the geometric properties of the printed components. T2 - NDT-CE 2025 - The International Symposium on Nondestructive Testing in Civil Engineering CY - Izmir, Turkiye DA - 24.09.2025 KW - 3D concrete printing KW - Real-time monitoring KW - Quality control PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-645394 DO - https://doi.org/10.58286/31704 SN - 1435-4934 SP - 1 EP - 10 PB - NDT.net AN - OPUS4-64539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kocherla, Amarteja A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Embedded Sensors for Quality Control and Structural Integrity Monitoring of Large-scale 3DCP Structures N2 - In extrusion-based 3D concrete printing (3DCP), addressing challenges related to safety, reliability, and quality control is crucial for widespread adoption. Yet current limitations in monitoring material properties during and after printing hinder the development of effective 3DCP guidelines. Therefore, the development of an inline sensing system capable of real-time monitoring and adjustment of process parameters is necessary to overcome these challenges. Building upon an existing inline sensing system developed by BAM, which currently monitors material properties during printing and the geometry of the print post-extrusion, this study extends its capabilities to post-extrusion monitoring using embedded piezoelectric (PZT) sensors. These PZT sensors provide localized measurements of material changes through electrical impedance (EI) measurements without disrupting the printing process. By embedding these sensors in 3D printed structures, continuous monitoring is achieved from layer deposition through 1-day of hydration. To achieve this, initially, PZT sensors were developed with multiple layers of protective coatings. Two different 3D printed mixtures, each with different hydration behaviors, were utilized, and PZT sensors were strategically placed between printed layers to maintain their integrity. EI measurements were collected continuously from printing through 1 day of hydration. Analysis of amplitude and frequency changes in the EI response spectrum provided insights into material behavior post-printing. The study highlights how continuous monitoring of frequency and conductance can track structural builtup and property development of the material. Rapid changes in conductance measurements, immediately post-printing indicate swift structural built-up, while key hydration phases are reflected in frequency measurements. T2 - 34th Annual Conference and Exhibition on Non Destructive Evaluation & Enabling Technologies CY - Chennai, India DA - 12.12.2024 KW - Embedded Sensors KW - 3D Concrete Printing KW - Quality Control KW - Inline Sensing KW - Structural Integrity PY - 2025 SP - 1 EP - 8 PB - Springer Nature CY - Heidelberg AN - OPUS4-65305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönsee, Eric A1 - Hüsken, Götz A1 - Jeyifous, Olubunmi Anthony A1 - Mezhov, Alexander A1 - Strangfeld, Christoph T1 - Calculating rheological properties of fresh mortar for additive manufacturing based on experimental, multi-sensor data N2 - Additive manufacturing of concrete structures is a novel and emerging technology. Freecontouring in civil engineering, which allows for entirely new designs, is a significant advantage. Inthe future, lower construction costs are expected with increased construction speeds and decreasingrequired materials and workers. However, architects and civil engineers rely on a certain quality ofexecution to fulfil construction standards. Although several techniques and approaches demonstratethe advantages, quality control during printing is highly challenging and rarely applied. Due to thecontinuous mixing process commonly used in 3D concrete printing, it is impossible to exclude varia-tions in the dry mixture or water content, and a test sample cannot be taken as a representative samplefor the whole structure. Although mortar properties vary only locally, a defect in one layer duringprinting could affect the entire integrity of the whole structure . Therefore, real-time process monitor-ing is required to record and document the printing process.At the Bundesanstalt für Materialforschung und -prüfung (BAM) a new test rig for the additive man-ufacturing of concrete is built. The primary purpose is measuring and monitoring the properties of amortar during the printing process.The following study investigates an approach for calculating yield stress and plastic viscosity based onexperimentally recorded pressure data. The calculations assume that fresh mortar behaves as a Bing-ham fluid and that the Buckingham-Reiner-equation is applicable. A test setup consisting of rigid pipeswith integrated pressure sensors at different positions is utilized.Monitoring the printing process with different sensors is crucial for the quality control of an ongoingprocess. T2 - Non-Traditional Cement and Concrete 2023 Conference CY - Brno, Czech Republic DA - 25.06.2023 KW - 3DCP KW - Monitoring KW - Additive manufacturing KW - Rheology KW - Bingham fluid KW - Concrete printing PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598179 DO - https://doi.org/10.4028/p-EV4gPv SN - 1662-0356 VL - 145 SP - 131 EP - 139 PB - Trans Tech Publications CY - Baech AN - OPUS4-59817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric A1 - Hüsken, Götz A1 - Kocherla, Amarteja A1 - Strangfeld, Christoph T1 - A framework for characterising the reflection intensity of a 3D-CP mortar N2 - The growing interest of 3D Concrete Printing (3DCP) arises new challenges for quality control. A major challenge lies in evaluation of the interlayer bond strength. An optical approach is developed to monitor the surface properties of the printed layer. Commercial laser profile scanners are utilised to record the reflection intensity of the mortar’s surface. To be applicable in the printing process, the reflection intensity needs to be characterised for each material within the printable region and further effects, like geometry and environmental light, need to be considered. The presented work aims to provide a framework for implementing the laser reflection intensity to 3DCP monitoring. T2 - NDT-CE 2025 - The International Symposium on Nondestructive Testing in Civil Engineering CY - Izmir, Türkiye DA - 24.09.2025 KW - 3D Concrete Printing KW - In Situ Measurements KW - Laser reflection intensity PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643047 DO - https://doi.org/10.58286/31728 SN - 1435-4934 SP - 1 EP - 4 PB - NDT.net AN - OPUS4-64304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönsee, Eric A1 - Hüsken, Götz A1 - Kocherla, Amarteja A1 - Strangfeld, Christoph T1 - Influences of Surface Properties on the Reflection Intensity - Towards in Situ Monitoring During Early Age Hydration of CEM I N2 - Interlayer bonding in 3D concrete printing is influenced by the hydration progress and surface moisture of the previously printed layer. For effective quality control, continuous in situ monitoring of interlayer surface properties is required. This study investigated reflection intensity as a method for in situ measurements during the hydration of CEM I mixtures with varying retarder contents. Additional factors influencing the reflection intensity are also examined. Two laser line scanners with different wavelengths were used to track hydration over 72 h. Vicat tests and isothermal calorimetry served as reference methods. Across all the mixtures, the reflection intensity exhibited a repeatable pattern with five different stages. A sharp increase in intensity during the third stage was consistent with the acceleration period of hydration. These findings suggest that reflection intensity measurements could serve as a promising tool for evaluating interlayer bonding in 3D concrete printing. KW - In situ hydration monitoring KW - Cement KW - Optical methods KW - Reflection intensity KW - Additive manufacturing KW - Isothermal calorimetry PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653430 DO - https://doi.org/10.1007/s10921-025-01326-2 SN - 1573-4862 VL - 45 IS - 1 SP - 1 EP - 17 PB - Springer Nature AN - OPUS4-65343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönsee, Eric A1 - Jeyifous, Olubunmi Anthony A1 - Strangfeld, Christoph A1 - Hüsken, Götz T1 - Investigations on multi-sensor data for monitoring volume flow during the printing process N2 - Extrusion based 3D concrete printing (3DCP) is a growing technology because of its high potential for automating construction and the new possibilities of design. In conventional construction methods, a sample is taken to be representative for one material batch. However, in 3DCP continuous mixing is used which results in variations during the mixing process. Therefore, one sample is not representative for the entire structure. This leads to the necessity of continuous and real-time process monitoring. This study focuses on the variations of pressure and temperature which are caused by changes in the material due to the ongoing mixing process. Changes in material, which is transported downstream, are influencing sensor signals in different positions with a time delay. In the following, the data is analysed to investigate if the changing material and the so caused change in pressure can be used to calculate volume flow. T2 - Digital Concrete 2024 CY - Munich, Germany DA - 04.09.2024 KW - Additive manufacturing KW - In-line Monitoring KW - Volume Flow KW - Process Control PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:gbv:084-2024081513042 DO - https://doi.org/10.24355/dbbs.084-202408151304-0 SP - 1 EP - 3 AN - OPUS4-61001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -