Bond Behavior of Plain Bars in Concrete under Reversed Cyclic Loading

Abstract

Plain bars with a diameter of 10 mm are widely used in reinforced concrete buildings, and the bond behavior between the bars and concrete has an essential effect on the seismic performance of concrete structures. Thus, to assess the safety of old buildings and repaired buildings with normal concrete, it was necessary to further investigate the bond performance of the plain bars in the concrete. The bonding tests under monotonic and reversed cyclic loading were carried out on the specimens reinforced with plain bars, and the influences of concrete grade and embedment length on the bond behavior were taken into consideration. The results indicate the maximum bond stress under reversed cyclic loading is less than that under monotonic loading, and this is the same for corresponding slip for the same test parameters. The concrete compressive strength positively affects the maximum bond stress, whereas the embedment length has a negative effect. Based on the elasticity analysis and test data fitting, the expressions of bond stress at characteristic points on the bond stress–slip curves were carried out. Consequently, the bond stress–slip model was established, which could be applied to calculate the bond stress–slip relationships under monotonic and reversed cyclic loading. By comparison between the test curves and proposed model, a good agreement is observed, which indicates that the proposed model can be used to predict the bond stress–slip curve of plain bars in concrete.

Penentuan Batasan Tingkat Kerusakan Seismik Pada Bangunan Non-Engineered Di Pacitan

“…Tulangan polos banyak digunakan pada pembangunan rumah tinggal karena alasan lebih murah. Tulangan jenis ini memiliki lekatan dengan beton yang rendah sehingga tidak bisa mengembangkan kekuatan penuh saat menerima gaya tarik, terutama saat gempa dimana struktur menerima beban siklik (Zhao et al, 2023). Tulangan akan cenderung mengalami slip sebelum mencapai kekuatan lelehnya sehingga elemen struktur yang menggunakan tulangan polos tidak dapat memikul gaya sesuai yang diharapkan.…”

Damage State of Non-Engineered Residential Buildings Owing to Earthquakes: A Case Study in Pacitan Regency, Indonesia

“…2) are commonly used because of their affordability; however, their inadequate bond strength with concrete makes them unsuitable for seismic events, during which the structure is subjected to cyclic loading. A low bond strength means that the concrete cannot grip the plain reinforcement adequately, leading to slippage prior to reaching its yield strength; thus, the seismic performance of any structure using this reinforcement type must consider its tendency to slip [22], [23]. b) Non-conforming reinforcement diameter In the Pacitan region, residential structures are generally built using reinforced concrete, which is a combination of concrete and a reinforcement, which provides compressive and tensile capabilities.…”