钢筋混凝土矩形截面柱绕丝加固的受力性能

Behavior of exterior spirally reinforced concrete column with rectangular cross-section

采用200 t的压力试验机,对40根绕丝的钢筋混凝土矩形截面柱进行压力实验。针对绕丝的间距以及加载偏心距的不同进行了分组研究。结果表明,用绕丝加固的柱体可以提高承载能力和减少破坏时纵筋和混凝土的应变,并且提高的幅度随着绕丝间距的减小而增大。当绕丝间距为40 mm时,极限承载力提高5.5%,纵筋的应变提高了18%,混凝土的应变提高了38%,柱的延性能得到较大改善;绕丝加固法不适用于较大偏心受压柱。

The pressing tests on 40 exterior spirally reinforced concrete columns with rectangular crosssection were performed using a 200 t pressing test machine to gain an insight to the reinforcement. Specimens with different spiral pitches and different loading eccentricities were tested. It turn out that the exterior spiral reinforcement of the concrete column enhances the load bearing capacity of the column and the destructive strain of the longitudinal bar and the concrete, and the smaller the spiral pitch, the stronger the enhancement. When the spiral pitch equals to 40 ram, the ultimate load bearing capacity increases by 5. 5%, the destructive strain of the longitudinal bar and the concrete increases by 18% and 38% respectively. The ductility of the column is greatly improved by the exterior spiral reinforcement, which, unfortunately, is not appropriate for the columns pressed by loading with large eccentricity. The obtained results provide a basis for the application of the exterior spiral reinforced concrete column in the engineering practice.