Gökhan Cevikbilen, Tugba Kuru, Akif Kutlu, Osman Bulut
{"title":"An Analysis of Soil–Pipe Interaction in Sand by Photoelastic Approach and an Analytical Approximation","authors":"Gökhan Cevikbilen, Tugba Kuru, Akif Kutlu, Osman Bulut","doi":"10.1002/nag.3977","DOIUrl":null,"url":null,"abstract":"In‐situ stress condition is an important aspect of buried unpressurized pipelines. Empirical approaches used for preliminary design are usually based on observations, which may be associated with some errors related to the measurement method. The photoelastic approach represents an alternative, nonintrusive measurement technique to model the plane stress‐strain behavior of buried pipes under different surcharge and groundwater conditions. Based on this approach, two model tests <jats:italic>M1</jats:italic> and <jats:italic>M2</jats:italic> were conducted to demonstrate the effects of soil arching on a pipe model buried in river sand and manufactured sand, which have similar granulometry but different angularity. In the dry state, the higher arching effect between the round particles of the river sand leads to a lower settlement and a smaller change in the stress and diameter of the pipe in <jats:italic>M1</jats:italic> compared to <jats:italic>M2</jats:italic>. The finite element analysis confirms the experimental results quite well, while Iowa formula is sufficient to represent the diameter changes. However, after a loading and unloading cycle, <jats:italic>M1</jats:italic> shows larger settlements at saturation due to the loss of arching effect in contrast to <jats:italic>M2</jats:italic>. The redistribution of the round particles and the re‐arching in a denser state lead to a huge stress relief in the pipe of <jats:italic>M1</jats:italic>, while the interlocked angular particles prevent the diameter changes, so that the stresses observed in the pipe are mainly maintained in <jats:italic>M2</jats:italic> at unloading and saturation. Finally, a practical analytical model to determine the pipe deformation for the dry condition problem is proposed.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"216 1","pages":""},"PeriodicalIF":3.4000,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal for Numerical and Analytical Methods in Geomechanics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1002/nag.3977","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}
引用次数: 0
Abstract
In‐situ stress condition is an important aspect of buried unpressurized pipelines. Empirical approaches used for preliminary design are usually based on observations, which may be associated with some errors related to the measurement method. The photoelastic approach represents an alternative, nonintrusive measurement technique to model the plane stress‐strain behavior of buried pipes under different surcharge and groundwater conditions. Based on this approach, two model tests M1 and M2 were conducted to demonstrate the effects of soil arching on a pipe model buried in river sand and manufactured sand, which have similar granulometry but different angularity. In the dry state, the higher arching effect between the round particles of the river sand leads to a lower settlement and a smaller change in the stress and diameter of the pipe in M1 compared to M2. The finite element analysis confirms the experimental results quite well, while Iowa formula is sufficient to represent the diameter changes. However, after a loading and unloading cycle, M1 shows larger settlements at saturation due to the loss of arching effect in contrast to M2. The redistribution of the round particles and the re‐arching in a denser state lead to a huge stress relief in the pipe of M1, while the interlocked angular particles prevent the diameter changes, so that the stresses observed in the pipe are mainly maintained in M2 at unloading and saturation. Finally, a practical analytical model to determine the pipe deformation for the dry condition problem is proposed.
期刊介绍:
The journal welcomes manuscripts that substantially contribute to the understanding of the complex mechanical behaviour of geomaterials (soils, rocks, concrete, ice, snow, and powders), through innovative experimental techniques, and/or through the development of novel numerical or hybrid experimental/numerical modelling concepts in geomechanics. Topics of interest include instabilities and localization, interface and surface phenomena, fracture and failure, multi-physics and other time-dependent phenomena, micromechanics and multi-scale methods, and inverse analysis and stochastic methods. Papers related to energy and environmental issues are particularly welcome. The illustration of the proposed methods and techniques to engineering problems is encouraged. However, manuscripts dealing with applications of existing methods, or proposing incremental improvements to existing methods – in particular marginal extensions of existing analytical solutions or numerical methods – will not be considered for review.