Large-diameter buried pipeline was widely used because of its energy-saving advantage and high efficiency. In this paper, "L"-type heat pipe network was taken as the research object, which was studied using the flow-heat-solid coupling method. The ANSYS Workbench platform was used to simulate heat transfer and the flow of the medium in the pipe network. The pressure and temperature of the flow field and the temperature, equivalent stress, and total deformation of the solid structure under different conditions were calculated, and the effects of different mediums on the variables of the temperature were compared. According to the theory of stress classification, stability analysis method was used to check the strength of the pipe network structure. Results show the stress and deformation of the anchorage section of the pipe network were mainly affected by the temperature of the fluid. When the pressure and temperature loads worked individually or simultaneously, maximum deformation occurred in the lateral region of the long arm near the elbow, and the maximum equivalent stress position changed according to the load change. When the medium temperatures were 60 degrees C and 80 degrees C, the strength of the pipe network structure satisfied the requirements according to the structural strength check analysis. (C) 2017 Elsevier Ltd. All rights reserved.