具有内核伸出段的套管构件在线接触阶段的受力性能研究

Study on the stress performance of the on-line contact stage of casing components with kernel outstretched segment

针对具有内核伸出段的轴压套管构件,建立了线接触阶段的力学模型;利用小挠度理论推导出了内核和套筒的剪力、弯矩、挠度、分布接触力、集中接触力等物理量的计算公式。通过与无内核伸出段套管构件的对比算例验证了本文相关物理量推导的正确性,分析了内核与套管在不同刚度比下相关物理量的变化情况。结果表明:由于内核伸出段的影响,点接触会提前向线接触变化,使套管构件的轴向承载力显著下降,端部的接触反力及内核的剪力、弯矩有显著的增加。对具有内核伸出段的套管构件进行了力学性能分析,结果表明:内核与套筒的间隙对线接触长度没有影响,内核的弯矩、剪力随着间隙的增加而增大;随着内核伸出段长度的增加,线接触长度及内核的弯矩、剪力增大。

Aiming at the axially compressed casing members with core extension section,the mechanical model of line contact stage is established.The formulas for calculating physical quantities such as shear force,bending moment,deflection,distributed contact force and concentrated contact force of core and sleeve are derived by using the theory of small deflection.Firstly,the correctness of the deduction of the related physical quantities is verified by a comparison example with the casing component without core extension section.Meanwhile,numerical example shows that the point contact will change to the line contact ahead of time due to the influence of the core extension section,which makes the axial bearing capacity of the casing member decrease remarkably,and the contact reaction force at the end and the shear force and bending moment of the core increase remarkably.Secondly,the mechanical properties of casing members with core extension section are analyzed.The analysis shows that the gap between core and sleeve has no effect on the line contact length,and the bending moment and shear force of core increase with the increase of the gap.With the increase of the length of core extension section,the line contact length and the bending moment and shear force of core also increase.