轴压作用下双金属复合管组合作用与承载力分析

Study on composite action and bearing capacity of the offshore lined pipe under axial compression

为探究轴压作用下双金属复合海底管道的组合作用与承载性能,对双金属复合海底管道进行了试验研究和理论分析。开展了不锈钢衬管材料性能试验,对比了国际主流不锈钢本构关系模型和试验结果。利用ABAQUS建立了精细化的双金属复合管道轴压试验有限元模型,系统研究了关键参数如复合工艺产生的环向复合应力、钢管初始缺陷幅值等对双金属复合管在轴压作用下力学性能的影响规律。通过对比已有轴压双金属复合管道试验结果,验证有限元模型。基于验证的有限元模型,对轴压作用下双金属复合管道的组合作用以及径厚比和材料强度对承载力的影响进行了分析。结果表明双金属复合管道的轴压极限承载力主要取决于基管的截面屈服荷载,并随着管径和材料强度的提高而增大。并依据分析结果对双金属复合海底管道的设计提出建议。

In order to explore the composite action and bearing capacity of the offshore lined pipe under axial compression, the experimental study and theoretical analysis of the offshore lined pipe are carried out in this study.The coupon test of liner pipe of stainless steel was carried out, and the constitutive model of international mainstream stainless steel and test results were compared.A fine finite element model of the offshore lined pipe under axial compression was established by ABAQUS.The influence of key parameters such as the residual hoop stress produced by the composite process and the initial imperfection amplitudes on the mechanical properties of lined pipe under axial compression was studied systematically.The finite element model was verified by comparing the experimental results of the existing axial compression lined pipe.Based on the validated finite element model, the effects of the composite action, diameter-thickness ratio and material strength on the bearing capacity of lined pipe under axial compression were analyzed.The results show that the ultimate bearing capacity of the offshore lined pipe mainly depends on the yield load of the cross section of outer pipe and increases with the increase of diameter and material strength.Based on the analysis results, suggestions for the design of the offshore lined pipe are made.