钢管自密实混凝土轴压构件的静力性能试验

Experimental Study on Static Performance of the Self-Consolidating Concrete Filled Steel Tubular Members under Axial Compressive Load

目的研究钢管自密实混凝土轴压构件的静力性能,为辽宁省相关地方标准的编制提供参考依据.方法通过18个钢管自密实混凝土轴压构件(内填混凝土的立方试块抗压强度达96 MPa)的静力试验,对轴压构件的破坏模态、轴力-中截面挠度曲线、轴力-应变曲线和侧向挠曲线形状等进行了分析.结果环向应变沿截面周边分布不均匀;纵向受拉区钢管对核心混凝土的环向约束效果不显著;钢管纵向应变沿截面高度的分布基本符合平截面假定;构件的挠曲线大致为正弦半波曲线.从试验研究的整体情况来看,浇筑强度达96 MPa的混凝土的钢管自密实混凝土与普通钢管混凝土在静力性能方面没有本质区别.结论构件的轴力-中截面挠度曲线可以分为弹性阶段、弹塑性阶段和下降阶段;构件的破坏属于延性破坏.

The static performance of the axially compressed self-consolidaing concrete filled steel tubular members were investigated in order to provide foundation for drawing the relative code of Liaoning prov- ince. On the basis of experimental study on 18 axially compressed self-consolidaing concrete filled steel tubu- lar members （the cubic compressive strength of the in-filled concrete is of 96 MPa）, the deformed modes, the axial load versus mid-height cross-section deflection curves, the axial load versus strain curves, the deflection curve and so on were analyzed. It was found that, the circumferential strain are not uniform along circular di- rection and steel tube that under longitudinal tension has no confinement effect on the concrete nearby, also, distribution of the longitudinal strain of the steel tube along cross-section satisfies with the plane-section as- sumption, in addition, deflection curve of the member is close to the sine curve. The axial load versus mid- height cross-section deflection curve of the members can be divided into elastic, elasto-plastic and softening stages and failure of the member showed ductility property.