Abdkader Anwar, Penzel Paul, Friese Danny, Overberg Matthias, Hahn Lars, Butler Marko, Mechtcherine Viktor, Cherif Chokri
Institute of Textile Machinery and High Performance Material Technology (ITM), Technische Universität Dresden, 01062 Dresden, Germany.
Institute of Construction Materials, Technische Universität Dresden, 01062 Dresden, Germany.
Materials (Basel). 2023 Mar 20;16(6):2459. doi: 10.3390/ma16062459.
Textile reinforcements have established themselves as a convincing alternative to conventional steel reinforcements in the building industry. In contrast to ribbed steel bars that ensure a stable mechanical interlock with concrete (form fit), the bonding force of smooth carbon rovings has so far been transmitted primarily by an adhesive bonding with the concrete matrix (material fit). However, this material fit does not enable the efficient use of the mechanical load capacity of the textile reinforcement. Solutions involving surface-profiled rods promise significant improvements in the bonding behavior by creating an additional mechanical interlock with the concrete matrix. An initial analysis was carried out to determine the effect of a braided rod geometry on the bonding behavior. For this purpose, novel braided rods with defined surface profiling consisting of several carbon filament yarns were developed and characterized in their tensile and bond properties. Further fundamental examinations to determine the influence of the impregnation as well as the application of a pre-tension during its consolidation in order to minimize the rod elongation under load were carried out. The investigations showed a high potential of the impregnated surface-profiled braided rods for a highly efficient application in concrete reinforcements. Hereby, a complete impregnation of the rod with a stiff polymer improved the tensile and bonding properties significantly. Compared to unprofiled reinforcement structures, the specific bonding stress could be increased up to 500% due to the strong form-fit effect of the braided rods while maintaining the high tensile properties.
在建筑行业中，纺织增强材料已成为传统钢筋的一种令人信服的替代品。与确保与混凝土形成稳定机械互锁（形状配合）的带肋钢筋不同，光滑碳纤维束的粘结力目前主要通过与混凝土基体的粘结（材料配合）来传递。然而，这种材料配合无法有效利用纺织增强材料的机械承载能力。涉及表面异形杆的解决方案有望通过与混凝土基体形成额外的机械互锁，显著改善粘结性能。进行了初步分析，以确定编织杆几何形状对粘结性能的影响。为此，开发了由多根碳纤维纱线组成、具有特定表面轮廓的新型编织杆，并对其拉伸和粘结性能进行了表征。还进行了进一步的基础研究，以确定浸渍的影响以及在固结过程中施加预张力，以尽量减少加载时杆的伸长。研究表明，浸渍后的表面异形编织杆在混凝土增强材料中具有高效应用的巨大潜力。在此，用刚性聚合物对杆进行完全浸渍可显著改善拉伸和粘结性能。与无轮廓增强结构相比，由于编织杆强大的形状配合效应，在保持高拉伸性能的同时，比粘结应力可提高高达500%。
