Stress characteristics of double-row glass fiber-reinforced plastic pipe culvert with sand and optimization of load reduction parameters under adverse conditions

Abstract

In this study, the stress and deformation rules of the double-row fiber-reinforced plastic sand pipes under the two loading methods of single-pipe and double-pipe loading were discussed. First, the indoor full-scale test was used to analyze the single-tube pipe top loading. The 90° measurement point of the loaded pipe and the 270° measurement point of the adjacent pipe were the most unfavorable positions for the stress of the pipeline. Through investigating the influence of cover soil height, load level, and compaction on the mechanical index of the most unfavorable load-bearing measuring point of the pipeline, the height of the overburden is found to be the most significant factor affecting the double-pipe stress system. Second, the numerical calculation model of the stress of the double-row pipeline was established to analyze the stress and deformation of the pipe culvert when the spacing of the double pipe was changed. The results indicated the critical spacing equivalent to the stress of the single pipe was 2.5D. Finally, the numerical method was also used to optimize the parameter of the geogrid at the top of the pipe in the most unfavorable stress state of the double pipe with 550-mm pipe spacing and double-loaded mode.

Deformation properties of arched glass fiber reinforced plastics structure under static load: Considering the soil cover and rise-span ratio

“…The test results of model box were shown in Figure 7. With the increase of load value, the hoop strain, radial deformation, and soil stress of arch GFRP structure all increased significantly, which had been confirmed in many studies (Guedes, 2009;Roham and Farshid, 2014;Saghir et al, 2021;Wang et al, 2021). As shown in Figure 7(a) and (b), when the external load increased by 50 kN, the hoop strain of the semi-circular GFRP structure increased by about 47% at measuring point 1, 40% at measuring point 2, and 46% at measuring point 3.…”