The cracking pattern and spacing in reinforced concrete (RC) structures considerably influence structural performance. Cracking may be severe with the utilization of fiber reinforced polymer (FRP) bars as compared to steel due to its low modulus of elasticity. In this study, the crack initiation, propagation and spacing, failure mode and ultimate load of RC beams reinforced with steel, basalt FRP (BFRP) and carbon FRP (CFRP) were investigated. A four-point bending test was conducted on fifteen RC beams. The beams with FRP bars exhibited worse cracking resistance and faster propagation throughout the loading process than those including steel bars. The cracking pattern was associated with failure modes from flexural to flexural-shear failure, which ultimately influenced the failure load. Furthermore, the crack spacing was analytically evaluated by three models used in conventional RC structures. The results showed that incorporating the rebar-concrete bond strength in Zhang's model resulted in more precise analytical values. Then, the bond strengths of all the FRP-concrete beams were evaluated by four codes. A strong correlation between the analytical and experimental crack spacing values was observed when considering code Canadian Standard Association (CSA) S806-12, and a significant margin of safety was obtained when considering the Japanese Society of Civil Engineering (JSCE) code.

钢筋混凝土（RC）结构的开裂模式和间距会极大地影响结构性能。与钢相比，由于纤维增强聚合物（FRP）筋的使用，其开裂可能很严重，因为其弹性模量低。本研究研究了钢筋，玄武岩FRP（BFRP）和碳FRP（CFRP）加固的RC梁的裂纹萌生，扩展和间距，破坏模式以及极限荷载。在15个RC梁上进行了四点弯曲测试。与包括钢筋的梁相比，具有FRP钢筋的梁表现出更差的抗裂性，并且在整个加载过程中传播更快。裂纹形态与从弯曲到弯曲剪切破坏的破坏模式有关，最终影响破坏载荷。此外，裂纹间距是通过常规RC结构中使用的三个模型进行分析评估的。结果表明，将钢筋混凝土粘结强度纳入张氏模型可以得到更精确的分析值。然后，通过四个代码评估所有FRP混凝土梁的粘结强度。当考虑代码加拿大标准协会（CSA）S806-12时，观察到的分析间距与实验裂缝间距值之间具有很强的相关性，而当考虑日本土木工程学会（JSCE）代码时，则获得了很大的安全裕度。所有玻璃钢混凝土梁的粘结强度通过四个规范进行评估。当考虑代码加拿大标准协会（CSA）S806-12时，观察到的分析间距与实验裂缝间距值之间具有很强的相关性，而当考虑日本土木工程学会（JSCE）代码时，则获得了很大的安全裕度。所有玻璃钢混凝土梁的粘结强度通过四个规范进行评估。当考虑代码加拿大标准协会（CSA）S806-12时，观察到的分析间距与实验裂缝间距值之间具有很强的相关性，而当考虑日本土木工程学会（JSCE）代码时，则获得了很大的安全裕度。