Basalt fiber is more cost-effective than carbon fiber and has superior mechanical and chemical properties than glass fiber. Most existing studies considered the use of micro basalt fibers in concrete matrix to reduce shrinkage and control micro cracks. However, macro fibers are often required to reinforce concrete material when large deformation and macro cracks in structural elements are of concern. Very few studies have been reported for macro Basalt Fiber Reinforced Polymer (BFRP) fibers to improve mechanical properties of concrete. The geometric characteristics of macro fibers are critical for concrete reinforcement. It is known that macro fibers with smooth surface possess poor bond strength. To enhance the bonding properties between macro BFRP fibers and concrete, in this experimental study, pullout tests on macro BFRP fibers with various geometric forms from different grades of mortar matrix were carried out. Smooth fiber, etched fiber and double-helix fiber were manufactured and evaluated. The effects of embedded length and matrix strength are also investigated through pullout behavior of single BFRP fiber. The variation of etched intervals of etched fibers on bond strength was also taken into account. It was found that the double-helix fiber outperformed other types of fibers in terms of strength utilization ratio and energy absorption capability. An empirical model for interfacial bond-slip relation was proposed based on the test results. Based on results of pullout tests, the outstanding performance of double-helix BFRP fiber was further verified by examining the mechanical properties of normal-strength concrete specimens reinforced with different types of macro BFRP fibers.

玄武岩纤维比碳纤维更具成本效益，并且比玻璃纤维具有更优越的机械和化学性能。大多数现有研究考虑在混凝土基体中使用微玄武岩纤维来减少收缩和控制微裂缝。然而，当结构元件中的大变形和宏观裂缝受到关注时，通常需要宏观纤维来加固混凝土材料。对宏观玄武岩纤维增强聚合物 (BFRP) 纤维改善混凝土力学性能的研究很少。粗纤维的几何特性对于混凝土加固至关重要。众所周知，表面光滑的粗纤维结合强度较差。为了增强宏观 BFRP 纤维与混凝土之间的粘结性能，在本实验研究中，对来自不同等级砂浆基质的具有各种几何形状的宏观 BFRP 纤维进行了拉拔试验。制造并评估了光滑纤维、蚀刻纤维和双螺旋纤维。还通过单根 BFRP 纤维的拔出行为研究了嵌入长度和基体强度的影响。还考虑了蚀刻纤维的蚀刻间隔对结合强度的变化。结果表明，双螺旋纤维在强度利用率和能量吸收能力方面优于其他类型的纤维。根据试验结果提出了界面键滑关系的经验模型。根据拉拔试验的结果，