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This paper presents an experimental study on 18 specimens, including 15 polyvinyl chloride (PVC)‐carbon fiber‐reinforced polymer (CFRP) tube confined reinforced concrete beams with longitudinal CFRP sheets (PCT‐RCBs‐LCS) and 3 PVC‐CFRP tube confined reinforced concrete beams (PCT‐RCBs). The effects of five studied parameters, such as longitudinal reinforcement rate (ρs$$ {\rho}_{\mathrm{s}} $$), concrete strength grade (Sc$$ {S}_{\mathrm{c}} $$), width (df$$ {d}_{\mathrm{f}} $$) and number (nf$$ {n}_{\mathrm{f}} $$) of longitudinal CFRP sheet, and specimen dimensions (Ds$$ {D}_{\mathrm{s}} $$), on the failure mode and flexural capacity are investigated. The PCT‐RCBs‐LCS with lower df$$ {d}_{\mathrm{f}} $$ and nf$$ {n}_{\mathrm{f}} $$ fail by the breakage of the PVC tube and the fracture of longitudinal CFRP sheets. Conversely, the cracking of PVC tube dominates the damage of the PCT‐RCBs‐LCS with higher df$$ {d}_{\mathrm{f}} $$ and nf$$ {n}_{\mathrm{f}} $$, while the longitudinal CFRP sheets are not broken. The introduction of longitudinal CFRP sheets can significantly improve the flexural capacity. The ultimate flexural capacity of the PCT‐RCBs‐LCS increases as the ρs$$ {\rho}_{\mathrm{s}} $$, sc$$ {s}_{\mathrm{c}} $$, df$$ {d}_{\mathrm{f}} $$, nf$$ {n}_{\mathrm{f}} $$ or Ds$$ {D}_{\mathrm{s}} $$ increases. In addition. considering the influence of RC beam section shape, a model for predicting the ultimate flexural capacity of the PCT‐RCBs‐LCS is proposed based on the limit equilibrium theory and cross‐sectional strain relationship. The predicted results of the proposed model agree well with test data. [ABSTRACT FROM AUTHOR]

• The failure mode of the PCCBCJs under eccentric compression was found. • The effects of several important parameters on bearing capacity, strains of the PCCC columns and longitudinal steel bars were examined. • A finite element model for the PCCBCJs under eccentric compression was established, the parametric studies were conducted and some design suggestions and construction requirements were proposed. Eleven PVC-CFRP Confined Concrete Beam – Column Joints (PCCBCJs) under eccentric compression are experimentally investigated to determine their mechanical behaviors. All the PCCBCJs are designed depending on the doctrine of weak joint and strong column, and four studied parameters including the reinforcement ratio, height and width of the ring beam, and eccentricity are examined. The test results indicate that all the PCCBCJs are damaged by the crushing of the joint concrete and the PVC tubes, as well as CFRP strips, are not broken. The ultimate bearing capacity of the PCCBCJs will be increased by raising the reinforcement ratio, width of the ring beam. Nevertheless, the increase in the ring beam height or eccentricity decreases the ultimate bearing capacity of the PCCBCJs. The effects of the studied parameters on the strains of the PVC-CFRP Confined Concrete (PCCC) columns, strains of the longitudinal steel bars, strains of the column stirrups, strains of the stirrups of the ring beam and strains of the annular steel bars are examined. An appropriate finite element model for the PCCBCJs under eccentric compression is established depending on the reasonable constitutive relation of the materials. Additionally, the parametric studies are conducted based on the validated finite element model, the stress mechanism is revealed and the influence of six main parameters on the bearing capacity is analyzed. Finally, some design suggestions and construction requirements are put forward. [ABSTRACT FROM AUTHOR]