Force analysis of suspended pipeline in collapsible loess areas based on elastic plastic foundation model

Key words:  suspended pipelines  elastic plastic foundation model  Winkler foundation model  axial loads  foundation rigidity  collapsible loess  analysis

Abstract:

According to the mechanics features of suspended pipelines in collapsible loess area, an elastic plastic foundation model (EPFM) was built up to obtain the forces and deformations of pipeline. The axial loads of pipelines and foundation plastic deformations were considered in the EPFM. The calculating equations of pipeline forces and deformations were deduced. The calculating software was programmed based on the equations and an actual suspended pipeline in collapsible loess area was calculated as example. The calculated results were compared with measured values and the results by Winkler model. The influences of axial loads and foundation rigidities were studied. The comprehensive results indicate that the EPFM is more accurate and suitable than Winkler model. The axial load has great influence on the calculating results, which could not be neglected during the verification and design of suspended pipelines in collapsible loess area. The foundation rigidity has little influence on the pipeline stresses and deformations in the EPFM.