عنوان مقاله [English]
The effect of internal and external forces on the transmission and distribution networks of potable municipal water makes more problems in the Iran water and waste water Corporation. Therefore, analyzing loaded forces is very important. Pipe insertion in the trenches, the channel filler material tend to have subsidence because of its reload and the channel subsidence on its bed causes trenches and the soil column above the channel move downward compared to adjacent undisturbed soils. The mentioned phenomena and its modeling are not considered along with many water pipeline designs. Thereafter, the current case study is presented. In order to evaluating this research, the data of flexible steel pipeline with large diameter is gathered from Mashhad Abfay company and its modeling is done with 5 atmospheres internal pressure in Ansys finite element software. The more credibility is satisfied with selecting the current elements of Ansy’s Plane 42 and Plane 82. The output results showed 8/5 mm mean subsidence in the pipe and also 5 cm in the asphalt surface. Amount of subsidence in the element Plane 42 was about 0/6 mm less than average. Subsidence process was similar in both elements and was in accordance with the assumptions. In one hand, Plane 82 element was found that due to damping by considering the characteristics and volume of soil, more efficient than other element in determining the substrate deformation behavior and around the tube and on the other hand, the flexible pipes are tolerant to deformation and its preventive force against to stress concentration is higher than rigid channels.