双H形钢部分包覆钢-混凝土组合柱压弯试验研究

Experimental study of intersecting H-shaped PEC column subjected to axial and cyclic horizontal loads

欧规EN 1994-1-1中仅列入了双H形钢部分包覆钢-混凝土组合(PEC)构件的截面形式,但对其压弯承载力计算方法和截面构造都未予以明确规定。为此,设计了3类截面形式的正交双H形钢PEC柱试件,对其进行了压弯条件下的往复加载试验,并将试验结果与采用作者前期提出的单向压弯及双向压弯承载力计算方法的计算结果进行比较。结果表明:钢翼缘对混凝土有明显的约束作用;试件在单向压弯和双向压弯下具有相同的抗弯刚度和承载力,均表现出了良好的塑性变形能力和耗能性能,加强箍筋可以提高试件的延性;前期提出的压弯承载力计算方法得到的压弯承载力与试件结果相比偏于安全,而相比于欧洲规范EC4的计算方法又具有一定的经济性。

The EN1991-1-1 only introduces the cross-section form of intersecting H-shaped partially encased composite(PEC) members, but its calculation method and configuration are not specified clearly. To resolve this problem, three types of cross-section of intersecting H-shaped PEC columns were designed. The tests of five specimens were conducted under cyclic horizontal loading and constant axial compression. The experimental results are compared with the results obtained by the calculation method of the ultimate strength of cross-section proposed by the authors previously. The results show that the steel flange has obvious restraining effect on concrete;the specimen has the same bending stiffness and bearing capacity under uniaxial bending and biaxial bending;all specimens have good plastic deformation ability and energy dissipation performance, and the reinforcement of the stirrup can improve the ductility of the specimen. Compared with the test results, the flexural capacity obtained by the calculation method proposed by the author is relatively safe, and compared with the calculation results of European code EC4, it is more economical.