Del Savio Alexandre Almeida, Esquivel Darwin La Torre, de Andrade Silva Flávio, Agreda Pastor Joaquín
Civil Engineering Department, Universidad de Lima, Lima 15023, Peru.
Department of Civil and Environmental Engineering, Pontifícia Universidade Católica do Rio de Janeiro, Rio de Janeiro 22451-040, Brazil.
Polymers (Basel). 2023 Feb 11;15(4):909. doi: 10.3390/polym15040909.
The construction industry requires concrete with adequate post-cracking behavior for applications such as tunnels, bridges, and pavements. For this reason, polypropylene macrofibers are used, which are synthetic fibers that fulfill the function of providing residual strength to concrete. In this study, an experimental plan is carried out to evaluate the bending behavior of concrete reinforced with polypropylene fibers using the four-point bending test according to ASTM C1609. Three fiber dosages (3.6, 7.2 and 10.8 kg/m) and three fiber lengths (40, 50, and 60 mm) were used. The use of macro polypropylene fibers increased the post-cracking behavior of concrete. In addition, based on the experimentally obtained results and available literature data, a multivariable equation was developed to predict the concrete toughness as a function of the volume, slenderness, and modulus of elasticity of the fibers. A Pearson's correlation coefficient, r of 0.90, showed a strong correlation between the developed equation and the experimental data. From this equation, it was possible to determine the participation of the following parameters in calculating toughness. The participation or weight of the fiber's modulus of elasticity on the concrete's tenacity is 26%, the volume of the fiber is 39%, the slenderness is 19%, and the reinforcement index is 16%.
建筑行业需要具有足够的开裂后性能的混凝土，用于隧道、桥梁和路面等应用。因此，使用了聚丙烯粗纤维，它们是合成纤维，起到为混凝土提供残余强度的作用。在本研究中，根据ASTM C1609进行了一项实验计划，采用四点弯曲试验来评估聚丙烯纤维增强混凝土的弯曲性能。使用了三种纤维用量（3.6、7.2和10.8千克/立方米）和三种纤维长度（40、50和60毫米）。聚丙烯粗纤维的使用提高了混凝土的开裂后性能。此外，基于实验获得的结果和现有文献数据，开发了一个多变量方程，以预测作为纤维体积、长细比和弹性模量函数的混凝土韧性。皮尔逊相关系数r为0.90，表明所开发的方程与实验数据之间存在很强的相关性。从这个方程中，可以确定以下参数在计算韧性中的参与度。纤维弹性模量对混凝土韧性的参与度或权重为26%，纤维体积为39%，长细比为19%，增强指数为16%。
