Ro Kyong Min, Kim Min Sook, Lee Young Hak
Department of Architectural Engineering, Kyung Hee University, Deogyeong-Daero 1732, Yongin 17104, Republic of Korea.
Materials (Basel). 2023 Feb 1;16(3):1256. doi: 10.3390/ma16031256.
The concrete jacketing method for retrofitting old reinforced concrete (RC) columns should secure confinement and seismic performance under torsion as well as unidirectional later loads. In a previous study, a hybrid concrete jacketing method was proposed using steel wire mesh (SWM), steel grid reinforcement (SGR), which can replace reinforcement of existing concrete jacketing method, and using steel fiber non-shrinkage mortar (SFNM). These details can simplify the retrofitting process of the existing concrete jacketing method, and seismic performance was evaluated by conducting a cyclic loading test under unidirectional loading. In this paper, the torsional behavior of RC columns retrofitted with the hybrid concrete jacketing method was investigated. Four specimens were fabricated and conducted cyclic loading tests under two types of loading schemes, unidirectional and bidirectional loading, to examine the effect of the loading path. The strength and energy dissipation capacity of retrofitted columns with hybrid concrete jackets increased approximately eight times compared to the old RC columns under torsional loading. Therefore, the hybrid concrete jacketing method can improve torsional resistance.
用于旧钢筋混凝土（RC）柱加固的混凝土套箍法应确保在扭转以及单向侧向荷载作用下的约束作用和抗震性能。在之前的一项研究中，提出了一种混合混凝土套箍法，该方法使用钢丝网（SWM）、可替代现有混凝土套箍法中钢筋的钢格构增强材料（SGR）以及钢纤维无收缩砂浆（SFNM）。这些细节可以简化现有混凝土套箍法的加固过程，并且通过在单向加载下进行循环加载试验来评估其抗震性能。在本文中，对采用混合混凝土套箍法加固的RC柱的扭转性能进行了研究。制作了四个试件，并在单向和双向两种加载方案下进行循环加载试验，以研究加载路径的影响。在扭转荷载作用下，采用混合混凝土套箍加固的柱的强度和耗能能力比旧RC柱提高了约八倍。因此，混合混凝土套箍法可以提高抗扭能力。
