Experimental and numerical research on the bond‐slip behavior of square‐rebar reinforced concrete during the republic of China (1912–1949)

Abstract

Square-rebar reinforced concrete structures during the republic of China (ROC) have special material properties and structural characteristics. To perform nonlinear finite element simulations of this special type of structure more accurately, a specialized bond-slip constitutive model is built.Eighteen central pullout specimens were designed based on the ROC concrete mix proportions and the square-rebar. Then, the test data were fitted with the universal global optimization method and the minimum Euclidean distance point method was chosen to calculate the inflection point matrix of the bondslip constitutive model. Finally, the main factors influencing the bond-slip behavior of the ROC square-rebar reinforced concrete were analyzed. The research results show that the corrosion of the square-rebar produces a negative effect on the whole structure and a modified bond-slip regression curve considering the size effect is obtained. The research results can provide a scientific basis for the nonlinear calculation of ROC square-rebar reinforced concrete structures considering the bond-slip behaviors. Highlights• The universal global optimization method of bond-slip was used to fit the test data.• The minimum Euclidean distance point method and the minimum Mahalanobis distance point method were used to centralize the fitting inflection points.• A modified four-line bond-slip constitutive model considering the size effect was proposed for square-rebar reinforced concrete during the republic of China (1912China ( -1949.• Bond-slip behavior between concrete and rebar was modeled by finite element method.Discussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors' closure, if any, approximately nine months after the print publication.

Square-rebar corrosion-induced cover cracking and its time prediction for historical reinforced concrete buildings in China

“…tested 66 vintage steel rebars (30 round-rebars and 36 square-rebars), and found that, while the height of the ribs of these vintage steel rebars can meet the regulations of current standards, the space between the ribs and the relative rib area cannot. This finding indicated that the bond-slip property between vintage steel rebar and concrete might not meet the requirements of current standards, which was eventually proved by Zhang, Chun, and Jin et al (2020). Dong, Chun, and Xu et al (2017) performed an accelerated corrosion experiment on eight concrete specimens with old square-rebars.…”

A Durability Prediction Method for Historical Square Rebar Reinforced Concrete Buildings

“…The theoretical models and experiments in the standard [18] are all designed for round rebar components; however, according to the existing studies, the structural configuration design [23], the bond-slip behavior between rebar and concrete [24] and the rebar corrosion induced cracking model [25] for square rebar cases are very different from the round rebar cases.…”

“…Moreover, the ratio of the critical depth and the section length of the rebars were investigated; however, they did not establish an applicable calculation method. Zhang et al [24] performed experimental and numerical investigation on the bond-slip behavior of square rebar and concrete, and the experimental results revealed that the performance was substantially weaker than that of the current deformed round rebar. Subsequently, Zhang et al [28] performed a study for experimental and theoretical analysis for the shear capacity of the square rebar reinforced concrete beam.…”