使用预拱钢板对矩形预应力混凝土柱进行轴向加固

钢套常用于钢筋混凝土(RC)柱加固。之前的试验研究评估了钢套柱的延性和抗剪性能。然而,实践中常使用预压轴向荷载对RC柱进行加固。尚未对预应力引起的传统柱和新型套管之间的应力滞后效应进行研究。使用一种简单的新型卸载方法,利用预拱钢板提高预应力RC柱的轴向承载力,试验证明该方法能够有效提高RC柱的轴向承载力。提出相应理论模型来计算钢板加固柱的轴向承载力,将模型的预测结果与试验结果相比较,验证了该模型的准确性。

Axial Strengthening of Preloaded Rectangular Concrete Columns by Precambered Steel Plates

Steel jacketing has been widely used for strengthening reinforced concrete (RC) columns. Previous experimental studies have evaluated the ductility and shear performance of steel jacketed columns. However, in practice, the RC columns to be strengthened are usually subjected to pre-compressed axial loads. The stress-lagging effect between the original column and the new jacket due to the pre-existing load has not been addressed previously. In this paper, a simple and innovative decompression approach, using precambered steel plates, is proposed to upgrade the axial capacity of preloaded RC columns. An experimental study was conducted to validate the effectiveness of this approach for increasing the axial load capacity of RC columns. A theoretical model was also developed to predict the axial load capacity of the plate-strengthened columns. Comparison of theoretical and experimental results showed that the theoretical model accurately predicted the axial load-carrying capacities of the plate-strengthened columns.