不锈钢管中管混凝土海洋平台导管腿轴压性能试验研究

不锈钢具有良好的耐腐性与变形能力，为研究海洋平台新型不锈钢导管腿轴压性能，通过12根不锈钢管中管混凝土柱的轴压力学性能试验，分析了空心率、混凝土强度、外钢管径厚比和材质对不锈钢管中管混凝土短柱轴压破坏模式、承载力等力学性能的影响。研究结果表明：不锈钢管中管混凝土短柱呈腰鼓型破坏，其塑性变形与屈服后应化强度比普通钢试件显著，但初始刚度比普通钢试件小；空心率和径厚比越小，试件承载力越大，空心率由0增加到0.61，试件承载力下降21%；径厚比由34减小到14，试件承载力提高63%；混凝土强度越高，试件承载力越大，混凝土由43.82MPa提高到59.37MPa，试件承载力提高11%。有限元模拟所得荷载-位移关系曲线、破坏形态和承载力均与试验结果吻合较好。

Experimental study on axial compressive behavior of concrete-filled double skin stainless steel tube jacket leg of offshore platform

Stainless steel has good corrosion resistance and deformability. An experimental study on twelve concrete-filled double skin stainless steel tubes was done under axial compression to investigate the mechanical behavior. The influences of the hollow ratio, concrete strength, diameter to thickness ratios and the mechanical properties on the mechanical performance such as failure modes and bearing capacity were discussed in detail. The results show that the failure mode of concrete-filled double skin stainless steel tube short columns is drum damage.The plastic deformation and post-yielding stress of concrete-filled double skin stainless steel tubes are more remarkable than those of ordinary steel specimens, but their initial stiffness are smaller than that of ordinary steel specimens. The specimens’ bearing capacity can be effectively improved by decreasing the hollow ratio and diameter to thickness ratio. When the hollow ratio increases from 0 to 0.61, the bearing capacity of the specimens decreases by 21%; When the diameter to thickness ratio decreases from 34 to 14, the bearing capacity of the specimens increases by 63%; the higher the concrete strength is, the greater the bearing capacity of the specimens is; the increase of the concrete strength from 43.82MPa to 59.37MPa can result in the increase of the bearing capacity of the specimens by 11%. The load-displacement curves, failure modes and ultimate load obtained by finite element simulation are in good agreement with the experimental results.