Load response and performance of protection of buriedflexible pipes reinforced by geogrids
长安大学学报(自然科学版)[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2020年3期
- Page:
- 63-74
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Load response and performance of protection of buriedflexible pipes reinforced by geogrids
- Author(s):
- XIAO Chengzhi1; AMANE Zarihun Tarafa1; 2; WANG Zihan1; LIU Kuan1
- (1. School of Civil and Transportation Engineering, Hebei University of Technology, Tianjin 300401, China;2. School of Civil Engineering and Architecture, Adama Science and Technology University,Adama 1888, Oromiya Region, Ethiopia)
- Keywords:
- bridge engineering; buried pipe; model test; geogrid; cyclic loading; reinforced soil
- PACS:
- -
- DOI:
- -
- Abstract:
- To solve the problem of frequently damaging the buried flexible pipes by outside force, the geosynthetic reinforced soil protection method was adopted to protect the flexible buried pipes. A series of laboratory model tests were performed to investigate the mechanical characteristics and deformation properties of flexible buried pipes,under static loads and cyclic loads and the performance of pipes reinforced by geogrids. The harmful load level was determined and the adaptable load range for reinforcement protection of pipes was presented. Furthermore, based on comprehensive comparison the quantitative and qualitative analysis were carried out to investigate the protection performance of buried pipes reinforced by geogrids under static and cyclic loading, and the optimum embedment parameters, such as embedment depth of the uppermost reinforcement, length of reinforcement, spacing of geogrid layers and geogrid layers of geogrids, were presented. The results show that the cyclic load can cause greater settlement of layer of the soil compare with static load. But cyclic load with low level has a small influence on the buried pipes, while the cyclic load with high level can cause great damage to pipe. Reinforcing by geogrids can reduce settlements of layers of soil and deformation of pipes,and alleviate the pressure of the soil around the pipe. In addition, for a level of loading around P is 0 to 300 kPa, the effect of protection with single layer reinforcement can be optimized, when the embedment depth of reinforcement and length of reinforcement is 0.4B (B is the width of load plate), 5D(D is the external diameter of pipe), respectively. However, the main effect of the single layer protection is not remarkably to control the ultimate deformation. For multilayer reinforcement with 3D buried depth of pipes, 5D length of reinforcement and 0.4B the embedment depth of top layer, the spacing of geogrid layers 0.5B, and geogrid layers N is 3, will not only delay settlement of the soil and the deformation of pipe significantly, but also control the ultimate deformation effectively. The multilayer reinforcement can significantly alleviate the pressure of the soil around pipe. The multilayer reinforcement can significantly alleviate the pressure of the soil around pipe, thus led the reinforcing to a desired result. The result of research provides theoretical support for the design and protection of buried pipelines under longterm complex loads such as traffic loads. 1 tab, 24 figs, 21 refs.
Last Update: 2020-06-03