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Investigation of Mechanical Properties of Structures Created with Use of Automatically Reinforced 3D Concrete Printing – Preliminary Study

Klik Przemysław, Cisowski Adam, Rządkowski Witold, Pyrzanowski Paweł, Kowalik Michał

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 5

41--50

EN

3D concrete printing (3DCP) technology is a rapidly developing and promising technique for creating concrete structures. One of the main challenges of the 3DCP technology is the method of reinforcement, which should be integrated with the automated printing process, while maintaining the best mechanical properties important for the strength of the structure. The main reason to undertake the subject is low degree of automation in construction industry, which results in high cost of human labour, as well as high rate of accidents in process. The article proposes a technology for automatic reinforcement of concrete structures with glass fibres and epoxy resin. Maximum bending force tests of beams reinforced with the proposed method were carried out and compared with beams reinforced with commonly used methods. Although not being a article focused on DIC analysis, few images were presented to compare behaviour of non-reinforced beam with automatically reinforced one and to show cracking propagation of a chosen automatically reinforced beam. The proposed method of reinforcement in the 3DCP process enables full automation and constructions with high bending strength, simultaneously reducing the level of risk involved in conventional construction industry.

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Reliability of printers 3DCP during continuous work

Figurski Aleksy, Cisowski Adam, Klik Przemysław, Kowalik Michał, Zapał Wojciech, Urbański Dawid, Zawiśliński Krzysztof, Lipowiecki Ignacy, Rządkowski Witold

Polish Technical Review

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2023

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No. 2

14--17

EN

The paper presents the studies on the reliability of printer Rebuild v3 during the implementation of the order of the Institute of Construction Technology. The object of the study was printing out of three miniature houses for fire tests and evaluation of burning ability of printouts made from the concrete. All the houses were printed during one session, lasting for 27h. Apart from the process of producing the objects, it was also possible to check the reliability and behaviour of the printer in so long and non-interrupted process.

PL

Artykuł przedstawia badania niezawodności drukarki REbuild v3 w trakcie realizacji zlecenia dla Instytutu Techniki Budowlanej. Przedmiotem badania było wydrukowanie trzech miniaturowych domków do testów ogniowych i oceny palności wydruków z betonu. Wszystkie domki zostały wydrukowane podczas jednej sesji trwającej 27 godzin. Poza samym procesem wykonania obiektów, udało się sprawdzić niezawodność i zachowanie drukarki w tak długim i nieprzerywanym procesie.

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Supported by 2D and 3D Imaging Methods Investigation of the Influence of Fiber Orientation on the Mechanical Properties of the Composites Reinforced with Fibers in a Polymer Matrix

Saraczyn Robert, Deroszewska Martyna, Kowaluk Tomasz, Skołek Emilia, Rządkowski Witold, Myszka Dawid

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 3

170--183

EN

The aim of this study was to examine the behavior of the carbon fiber reinforced polymer (CFRP) composites depending on the fiber orientation and to understand the influence of microstructural discontinuities on mechanical properties. For the tests 210 gsm prepreg composite and 200 gsm carbon fabric with polymer matrix have been used. Samples were structured and later examined according to the ASTM-D3039 and ASTM-D3878 (equivalents are ISO 20975, ISO 527-4 and ISO 527-5). Accordingly, to the number of layers, three ways of the fibers arranging in relation to the applied force were used. Mechanical properties were determined in a static tensile test. The results of imaging studies, which included analyzes of Digital Image Correlation, Computed Tomography and Scanning Electron Microscopy, showed structural discontinuities, specific stress distribution and propagation of stresses depending on the production technology, which were correlated with the obtained strength results. The source of the gradual development of the degradation of the composite structure was observed in local microdamages and microcracks. As a result of a sub-critical crack growth within the resin matrix material, the defects are subject to a complex, multi-axial stress field on the micro-scale, even if the globally applied force is axial. Samples in which the load was applied along the axis of the fibers behave like an elastic material, while samples, where the force is applied at an angle to the axis of the fibers, tend to behave like an elastic-plastic material.

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Combining the Technology of Long-Range Laser 3D Scanners and Structured Light Handheld 3D Scanners to Digitize Large-sized Objects

Lipowiecki Ignacy, Rządkowski Witold, Zapał Wojciech, Kowalik Michał

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 3

196--205

EN

This paper presents a new method of merging the results obtained with long-range laser 3D scanners and structured light handheld 3D scanners to digitalize large-sized objects. An overview of the solutions in which these types of scanners are used was conducted and combined with the analysis of the studies related to the measurement accu- racy they offer. The focus was on the problems that may arise during the digitization of detailed large-sized objects. A reference test object was then selected, which not only included the fine details that needed to be represented but also met the size criterion. The object was scanned by two 3D scanners and the data was then compared in various aspects, such as resolution, accuracy, and the measurement procedure. Significant discrepancies in the results were identified. They related to the resolution and quality of results as well as accuracy, reaching more than 20 mm. Therefore, a method of combining the results was developed to collate the advantages of both devices and elimi- nate their disadvantages. In the end, the analysis of obtained results was repeated and the results were presented.

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Pierwsze przemysłowe zastosowanie w Polsce technologii druku 3D z betonu

Ignerowicz Arkadiusz, Rządkowski Witold

Budownictwo, Technologie, Architektura

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2022

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nr 3

62--64

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Case Study of Composite Chassis Manufacturing Process Using Low Temperature Molds Tempered with Gradual Heat Annealing Process

Rządkowski Witold, Klik Przemysław, Tracz Jan, Kowalik Michał

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 3

12--21

EN

This case study describes a manufacturing process of composite chassis also known as monocoque. The structure is made using carbon fibre reinforced polymers (CFRP) which are manufactured in out-of-autoclave (OOA) process from pre-impregnated carbon fabrics and aluminium alloy honeycomb core. Since the material cost is high the aim of the project was to reduce the cost of manufacturing process i.e. cost of models and moulds. Therefore, instead of high-temp models and moulds a cheaper alternative was used. It consisted of Styrofoam models made using polyurethane (PU) paste and moulds made from CFRP using wet layup process which were cured at room temperature. Such moulds had to be adapted to withstand high temperatures during pre-preg cure. This was done with gradual heat annealing process which increased the maximum service temperature from 45C to 90C. This was enough for the low-temp cure of pre-preg material, but it might be possible to increase the temperature even further. As a result, the cost of manufacturing process had been reduced by 50%.

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Validation of Key Parameters Between Real and Computer Model of Suspension System Used in FSAE Vehicle

Ziemba Krzysztof, Tracz Jan, Rządkowski Witold, Kowalik Michał

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 3

65--74

EN

The aim of this paper was to determine the differences in the designed and manufactured model of a suspension. A set of key parameters was compared, including camber and toe in angles and their change w.r.t wheel travel, as well as the motion ratio. It also focused on the possibility of accurately determining the suspension system kinematics using affordable measuring devices available on the market. First, the design process, main goals and project assumptions were briefly described. Next, the CAD model and manufacturing process was presented. Finally, the measurements of both computer and real model were performed. The obtained results were compared and a significant difference between models was observed. The reason of such variation could not be determined unambiguously, as there were numerous factors that could potentially influence the results. Moreover, it was proven that accurate determination of kinematics is impossible using the given set of measuring devices.