2026-04-20T01:08:06Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/113862026-02-18T01:05:51Zcom_10259_4809com_10259_5086com_10259_2604col_10259_4810

Vicente Cabrera, Miguel Ángel Mena Alonso, Álvaro González Cabrera, Dorys Carmen Ruiz, Gonzalo Cifuentes, Héctor Leiva, Carlos Yu, Rena C. Mínguez Algarra, Jesús 2026-02-17T13:43:15Z 2026-02-17T13:43:15Z 2025-03 2045-2322 https://hdl.handle.net/10259/11386 10.1038/s41598-025-94471-7 2045-2322 The accurate determination of the tensile strength of concrete is a topic of growing interest, especially driven by the new ultra-high tensile strength fiber-reinforced concretes. However, this is a complex task, as traditional methods provide inconsistent results (both splitting tensile test and 3-point bending test). The most robust method is the direct tensile test. However, in concrete, it poses a technical challenge that has not yet been satisfactorily solved. The aim of this study is the design of a test specimen that maximizes the percentage of successful failure and also allows a viable anchorage solution to the load application equipment, especially for high and ultra-high tensile strength concretes. An optimized geometry of a bone-shaped specimen that maximizes the probability of collapse occurring at the central neck is presented. First, a mathematical function of the generatrix of the bone-shape specimen is presented. The behavior of the solution is also analyzed numerically and statistically, comparing it with other commonly used solutions for direct tensile tests. Additionally, the design, fabrication, and calibration of a tailored cardan joint for load centering, thus minimizing its eccentricity and the dispersion of the results. Finally, the results of a static test campaign carried out on six carbon-fiber reinforced high tensile strength concrete specimens. The proposed bone-shaped specimen shows a much higher percentage of successful failures than the other specimen geometries commonly used for tensile testing, which improves the quality of tensile characterization test campaigns for high and ultra-high tensile strength concretes. The authors are grateful for the financial support from the Ministerio de Economía y Competitividad, PID2019-110928RB-C31, PID2019-110928RB-C32 and PID2019-110928RB-C33, Spain. application/pdf eng Nature Research Scientific Reports. 2025, V. 15, 10820 https://doi.org/10.1038/s41598-025-94471-7 Attribution-NonCommercial-NoDerivatives 4.0 Internacional http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess Ultra-high strength concrete Direct tensile strength test Fiber-reinforced concrete Monte Carlo method Cardan joint Resistencia de materiales Hormigón armado Strength of materials Reinforced concrete Numerical and experimental study of the optimal specimen geometry for direct tension strength tests in high tensile strength fiber reinforced concrete info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Scientific Reports 15 1