EXPERIMENTAL TESTS OF FLAT CONCRETE ARCHES WITH TIGHTENING MANUFACTURED USING 3D PRINTING TECHNOLOGY

Since the end of the first quarter of the twenty-first century, social processes have been characterized by increasing dynamics, requiring a high level of mobility and adaptability from the construction industry. In response to these challenges, the emergence and continuous development of construction-scale 3D printing technology have created prerequisites for fundamental changes in construction practices. This technology enables the realization of buildings and structures with complex geometric forms that were previously difficult or economically impractical to construct using traditional methods. The use of automated construction processes based on pre-designed digital models allows the transformation of construction from a static, labor-intensive industry into a flexible digital ecosystem capable of rapidly adapting to changing functional and spatial requirements. At the same time, the transformation of construction technologies is not limited solely to structural elements such as load-bearing walls, partitions, or floor systems. Additive manufacturing technologies also open new possibilities for shaping the internal architectural environment by enabling the fabrication of complex bionic elements with optimized geometry. Such forms were previously considered technically infeasible or excessively expensive. As a result, 3D printing technology has the potential to change the role of architectural and structural elements, allowing them to function not only as passive components but also as active elements of an integrated built environment. Despite the rapid technological progress in construction 3D printing, the scientific basis for the structural behavior of 3D-printed load-bearing systems remains insufficiently developed. In particular, there is a lack of experimental data concerning the load-bearing capacity, deformability, and failure mechanisms of such structures. Existing design standards and regulatory documents do not adequately address the specific features of layered additively manufactured elements, which significantly complicates their structural analysis and practical implementation. This paper presents the results of experimental testing of shallow tied-arch structures manufactured using a construction 3D printer developed by the Ukrainian company UTU. The arches were produced using a layered printing process and subsequently subjected to controlled experimental loading. The testing methodology proposed and implemented by the authors is described in detail, including the loading scheme, boundary conditions, and measurement of structural response. Experimental investigations were carried out under the action of concentrated loads applied at the third points of the span, which allowed the assessment of the structural performance of the arches under realistic loading conditions. The obtained results provide valuable insights into the load-bearing behavior and deformation characteristics of 3D-printed shallow arch structures with ties and contribute to the formation of a reliable experimental basis for further analytical and numerical studies. These findings may serve as a foundation for the development of design recommendations and future regulatory approaches for additively manufactured structural systems.