Numerical Investigation on the Deformational Behavior of Continuous Buried Pipelines Under Reverse Faulting
- PDF / 3,096,509 Bytes
- 16 Pages / 595.276 x 790.866 pts Page_size
- 46 Downloads / 181 Views
RESEARCH ARTICLE-CIVIL ENGINEERING
Numerical Investigation on the Deformational Behavior of Continuous Buried Pipelines Under Reverse Faulting Amin Monshizadeh Naeen1 · Ehsan Seyedi Hosseininia1 Received: 13 February 2020 / Accepted: 1 July 2020 © King Fahd University of Petroleum & Minerals 2020
Abstract Steel pipelines are vulnerable to the movements of active faults. Few studies focused on reverse faults. The deformational behavior of buried steel pipelines crossing an active reverse fault is investigated in this paper by applying 3D continuum finite element modeling. Numerical simulations indicate that local buckling (or wrinkling) mode of failure is more sensitive to the pipeline rather than tensile failure mode. The results were also confirmed by the experiment. Based on parametric studies, the pipeline capacity against failure can be significantly improved by reducing the burial depth and the pipe thick‑ ness ratio. Besides, the soil consistency around the pipe has a great effect on the behavior of buried pipelines. Furthermore, it is found out that the failed pipeline sections would be generated in longer distance from the fault plane as the soil behaves more softly or the pipeline is more flexible. These findings can lead the designers to have a safer and economic design of pipelines crossing reverse faulting zones. Keywords Buried pipelines · Reverse fault · Geotechnical parameters · Numerical model List of Symbols c Soil cohesion Cc Coefficient of curvature Cu Coefficient of uniformity D Pipe diameter D50 The average particle size of soil E Soil elastic Young’s modulus E1 Elastic Young’s modulus of pipe E2 Plastic Young’s modulus of pipe Ei Initial Young’s modulus of pipe in the Ramberg– Osgood stress–strain equation f Friction factor Gs Specific gravity H Burial depth of the pipeline n Ramberg–Osgood parameter R Pipe radius r Ramberg–Osgood parameter t Pipe wall thickness
β Fault dip angle δ Interface angle of friction for pipe and soil γ Total unit weight of soil γd Dry unit weight of soil ε1 Initial yield strain of pipeline ε2 Failure strain of pipeline ɛc Compressive strain ɛt Tensile strain ɛu Ultimate strain εa Axial strain µ Coefficient of friction ν Poisson’s ratio σ0 Effective yield stress σ1 Initial yield stress of pipeline σ2 Failure stress of pipeline σa Maximum axial stress ϕ Internal friction angle of soil ψ Dilation angle of soil
* Ehsan Seyedi Hosseininia [email protected]
1 Introduction
Amin Monshizadeh Naeen [email protected] 1
Department of Civil Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, P.O. Box 91775‑1111, Mashhad, Iran
Failure of buried pipelines may occur because of natural events such as earthquake wave propagation and Permanent Ground Deformation (PGD). Previous investigations have proved that, unlike the surface structures, most of seismic
13
Vol.:(0123456789)
Arabian Journal for Science and Engineering
damages to pipelines were because of PGD such as fault movement, landslide, and
Data Loading...
