海底管道起吊时最佳吊点位置的选择

针对海洋管道的施工情况，提出了确定管中应力和吊点位置选择的两个问题。根据材料强度，认为起吊引 的管中应力不宜超过许用应力。为此，分析管子起吊的受力和变形，是选择海洋管道最佳起吊位置的保证。利用材料力学方法对此问题进行了分析。在应力分析中，研究了集中载荷单独作用、均布载荷单独作用端口位移条件等问题，并给出了相应计算公式；对于最佳吊点位置，除给出计算公式外，还以曲线形式给出了管中最大应力、悬空长度和提

Selection of the Optimal Lifting Point for Submarine Pipeline,

It is pointed out that two questions have to be answered in the submarine pipeline construction; the stresses in pipes and the location of the point to lift a pipe. The paper recommends that the stresses in pipe caused by lifting be below the allowable stress depending upon pipe strength, and that analysis on pipe stress and deformation during lifting operation be made to locate the most suitable point for pipe lifting. Analysis is made in the paper using the methods of mechanics of materials. In the stress analysis, such aspects are studied as the unaccompanied action of centralized loads, the unaccompanied action of uniform distributed loads and the conditions for pipe end displacement, with their calculation formula provided. For lifting point optimization, curves as well as formula are given, showing the maximum stress in pipe, the suspended length, and the variation of the suspended height of pipe end with the lifting force.