This study aims to optimize the mechanical behavior of alkali-activated mortar reinforced with polyacrylonitrile fibers. In order to accomplish this, ceramic waste from clay bricks and roof tiles was used as the primary precursor, which was then combined with ladle furnace slag and activated with sodium silicate. Thereby, fibers were added to improve its brittle behavior, namely its toughness and the residual flexural strength of the material, thus enabling its use in a myriad of applications within the construction sector. So, an extensive experimental campaign was carried out to assess the influence of polyacrylonitrile fibers content (0%, 0.5%, and 1% in volume) and the curing time (14, 28, and 90 days) on the main physical and mechanical properties, including capillarity, porosity, uniaxial compressive, and flexural strength. Microstructural analysis was accomplished with Scanning Electron Microscopy, X-ray Energy Dispersive Analyzer, X-ray diffraction, and Fourier Transform Infrared Spectroscopy. Experimental results of the developed mortars showed satisfactory mechanical properties, enhanced by the fibers, regardless of the fiber ratio added, attaining compressive and tensile under flexural strengths’ values up to 47 MPa and 7 N/mm², respectively, after 90 days of curing. Compared to non-reinforced mortars, these values represent an improvement of about 20% in both cases, thus justifying the addition of fibers.

本研究旨在优化聚丙烯腈纤维增强碱活化砂浆的力学性能。为了实现这一目标，粘土砖和屋顶瓦片的陶瓷废料被用作主要前体，然后与钢包炉渣混合并用硅酸钠活化。因此，添加了纤维以改善其脆性行为，即材料的韧性和残余弯曲强度，从而使其能够在建筑领域的无数应用中使用。因此，进行了广泛的实验活动以评估聚丙烯腈纤维含量（体积为 0%、0.5% 和 1%）和固化时间（14、28 和 90 天）对主要物理和机械性能的影响，包括毛细作用、孔隙度、单轴抗压和抗弯强度。微观结构分析是通过扫描电子显微镜、X 射线能量色散分析仪、X 射线衍射和傅立叶变换红外光谱完成的。开发的砂浆的实验结果显示出令人满意的机械性能，通过纤维增强，无论添加的纤维比例如何，在高达 47 MPa 和 7 N/mm 的弯曲强度值下均能获得抗压和抗拉强度²、分别固化90天后。与非增强砂浆相比，这些值在两种情况下都提高了约 20%，因此证明添加纤维是合理的。