Abstract: It is crucial to ensure the structural safety of buried steel pipes (BSP) as they are increasingly utilized in major water diversion projects, as the lifeline of these projects.However, current BSP structural calculation methods lack the consideration of pipe’s self-weight. In view of this, we developed a calculation method considering the self-weight of pipes based on the Spangler model theory, and compared the results with those of traditional and finite element methods. Results demonstrate that the proposed calculation method merely integrates the pipe weight term into the existing calculation equations, rendering it straightforward and convenient. The inclusion of pipe weight moderately increases pipe deformation by up to 20%. For pipes with substantial diameters and shallow cover depths, the self-weight should be taken into consideration, whereas for pipes with diameter less than 1 m or depth exceeding 4 m, the self-weight of pipes can be neglected. The proposed calculation method aligns more closely with the finite element method regarding pipe deformation patterns, with generally higher calculation accuracy compared to traditional methods. Moreover, the proposed calculation method is applicable to other typical buried flexible pipes.

Key words: buried steel pipe, pipe weight, Spangler model, pipe deformation, calculation method