Mechanical Analysis of Flexible Pipe during Installation

2015 ◽  
Vol 799-800 ◽  
pp. 645-650
Author(s):  
Hong Dong Qiao ◽  
Zhao Hui Shang ◽  
Wei Dong Ruan ◽  
Yong Bai
Keyword(s):  
Theoretical Model ◽  
Bending Moment ◽  
Element Model ◽  
Mechanical Analysis ◽  
Calculation Model ◽  
Flexible Pipe ◽  
Moment Distribution ◽  
Numerical Iteration ◽  
Iteration Program ◽  
Load Conditions

Mechanical analysis of flexible pipe during installation is presented in this paper. The configuration, tension and bending moment of the flexible are important issues during the installation. A reasonable theoretical model is proposed to handle the pipe configuration and the loads during installation. Numerical iteration program for the model is developed to get the tension, bending moment distribution and the pipe configuration. Two segments which are suspended segment and seabed segment are analyzed with different calculation model for their different load conditions and boundary conditions. Finite element model is established by Abaqus to verify the results from the theoretical model. The results from theoretical are very close to the ones got from FEM. Typical installation method J-lay method is applied to perform the FEM and numerical analysis.

Investigation on Mechanical Properties of Fiberglass Reinforced Flexible Pipes Under Bending

2019 ◽  
Author(s):  
Yifan Gao ◽  
Shan Jin ◽  
Peng Cheng ◽  
Peihua Han ◽  
Yong Bai
Keyword(s):  
Mechanical Behavior ◽  
Virtual Work ◽  
Experimental Studies ◽  
Bending Moment ◽  
Element Model ◽  
Bending Test ◽  
Flexible Pipe ◽  
Four Point Bending ◽  
Flexible Pipes ◽  
Bending Behavior

Abstract Fiberglass reinforced flexible pipe (FRFP) is a kind of composite thermoplastic pipe, which has many advantages compared to boned flexible pipes. This paper describes an analysis of the mechanical behavior of FRFP under bending. The bending behavior of FRFP was investigated by experimental, analytical and numerical methods. Firstly, this paper presents experimental studies of three 10-layer FRFP in a typical four-point bending test. Curvature-bending moment relations were recorded during the test. Then, based on the nonlinear ring theory and the principle of virtual work, a simplified method was proposed to study the mechanical behavior of FRFP. In addition, a finite element model (FEM) including reinforced layers and high density polyethylene (HDPE) layers was established to simulate the HDPE layers and reinforced layers, respectively. The result of Curvature-bending moment relations obtained from three methods agree well with each other, which proves that the simplified analytical model and FEM are accurate and reliable. The conclusions of this paper could be useful to manufacturing engineers.

Mechanical Behaviors of Metallic Strip Flexible Pipe Under Axisymmetric Loads

2018 ◽  
Author(s):  
Kaien Jiang ◽  
Ting Liu ◽  
Shuai Yuan ◽  
Yong Bai
Keyword(s):  
Theoretical Model ◽  
Element Model ◽  
Tensile Tests ◽  
Practical Application ◽  
Flexible Pipe ◽  
Promising Alternative ◽  
Mechanical Responses ◽  
External Pressures ◽  
Metallic Strip ◽  
Security And Reliability

Metallic Strip Flexible Pipe (MSFP) is regarded as a promising alternative for submarine pipelines. During the operation and service phases, MSFP will inevitably experience significant tension as well as internal and external pressures. In order to ensure the security and reliability of MSFP in the application, the mechanical responses of MSFP subjected to axisymmetric loads should be carefully estimated. In this paper, a theoretical model estimating the tension stiffness under axisymmetric loads is established, which takes the material plasticity into consideration. Additionally, a finite element model is developed by ABAQUS to verify the feasibility of the proposed theoretical model. The results from full-scale tensile tests of MSFP are also adopted to verify the proposed method’s validity in calculating its tension behavior. The coincidence between the results from different methods illustrates the accuracy and reliability of the proposed theoretical model. Based on the parametric study, some interesting conclusions have been obtained which may be useful for the practical application of MSFP.

Helical Wire Behavior of Unbonded Flexible Pipes Under Bending

2015 ◽  
Author(s):  
Yutian Lu ◽  
Huibin Yan ◽  
Yong Bai ◽  
Peng Cheng
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Axial Strain ◽  
Bending Moment ◽  
Element Model ◽  
Flexible Pipe ◽  
Slip Mechanism ◽  
Flexible Pipes ◽  
Bending Behavior ◽  
Unbonded Flexible Pipes

The bending behavior of unbonded flexible pipe is governed by the response of the helical wires in the tensile armor to bending. The behavior of the helical wire, especially the axial strain, is influenced by the slip mechanism as a result of an increasing curvature under bending. In the present paper, two limit curves are considered with a certain curvature. A 3-D finite element model using ABAQUS is developed to simulate the practical behavior of the helical wires under bending. By comparing the FEA and theoretical results, a basic conclusion about the real slip path of the helical wire between two limit curves is introduced. A hysteretic bending moment-curvature relationship induced by the slip mechanism is obtained from the finite element model as well.

scholarly journals Numerical Analysis of the Beam-Column Resistance Compared to Methods by European Standards

2021 ◽  
Vol 11 (7) ◽  
pp. 3269
Author(s):  
Jozef Prokop ◽  
Josef Vičan ◽  
Jozef Jošt
Keyword(s):  
Cross Section ◽  
Design Method ◽  
Bending Moment ◽  
Element Model ◽  
Point Of View ◽  
Beam Columns ◽  
Moment Distribution ◽  
European Standards ◽  
Fixed Beam ◽  
A Current

The optimisation of the design method for verification of slender steel beam-columns is still a current issue not only from scientific point of view, but also for design practice. Therefore, the main objective of this paper is comparison of the suitability of established design approaches, according to the European standards for steel and aluminium structures, on the basis of numerical simulations. Thus, a finite element model was validated on the basis of experimental analysis available in the scientific literature. To perform the comparison of accuracy of design approaches according to European standards, a commercial software program ANSYS was used for observation of the resistances of beam-columns. The resistance of european I beams with parallel flanges (IPE) and a rectangular hollow cross-section (RHS) were investigated for four load cases on a simply supported member and also on a pinned-fixed beam column with linear bending moment distribution, where the resistance of the cross-section governs. Finally, the conclusions for suitability of the respective design approaches are discussed, together with some findings that arose from this work.

Prediction of Internal Pressure of Flexible Pipe

2019 ◽  
Author(s):  
Qiangqiang Shao ◽  
Ting Liu ◽  
Shuai Yuan ◽  
Peihua Han ◽  
Yong Bai
Keyword(s):  
Theoretical Model ◽  
Oil And Gas ◽  
Virtual Work ◽  
Fluid Pressure ◽  
Oil And Gas Industry ◽  
Element Model ◽  
Petroleum Products ◽  
Burst Pressure ◽  
Flexible Pipe ◽  
Flexible Pipes

Abstract The flexible pipes are widely used in the oil and gas industry to transport petroleum products. The pipe might burst fails when a large internal fluid pressure acts on the pipe, and the consequences are disastrous. In order to ensure the security and reliability of flexible pipes in the application, the mechanical responses of the pipe subjected to high pressure loads should be carefully estimated. The main purpose of this paper is to investigate the burst pressure of the pipe. Based on the principle of virtual work, a theoretical model for stress and deformations of the pipe is established, which takes the material plasticity into consideration. In addition, a finite element model is developed by ABAQUS to verify the feasibility of the theoretical model. According to the verified model, it is efficient to predict the burst pressure and design its cross-section economically with its serving conditions.

Case study: Theoretical calculation model and variable condition analysis research on the water-splashing noise for natural draft wet cooling towers

2020 ◽  
Vol 68 (2) ◽  
pp. 137-145
Author(s):  
Yang Zhouo ◽  
Ming Gao ◽  
Suoying He ◽  
Yuetao Shi ◽  
Fengzhong Sun
Keyword(s):  
Theoretical Model ◽  
Sound Pressure Level ◽  
Water Droplet ◽  
Water Distribution ◽  
Sound Pressure ◽  
Cooling Tower ◽  
Distribution Patterns ◽  
Calculation Model ◽  
Pressure Level ◽  
Cooling Towers

Based on the basic theory of water droplets impact noise, the generation mechanism and calculation model of the water-splashing noise for natural draft wet cooling towers were established in this study, and then by means of the custom software, the water-splashing noise was studied under different water droplet diameters and water-spraying densities as well as partition water distribution patterns conditions. Comparedwith the water-splashing noise of the field test, the average difference of the theoretical and the measured value is 0.82 dB, which validates the accuracy of the established theoretical model. The results based on theoretical model showed that, when the water droplet diameters are smaller in cooling tower, the attenuation of total sound pressure level of the water-splashing noise is greater. From 0 m to 8 m away from the cooling tower, the sound pressure level of the watersplashing noise of 3 mm and 6 mm water droplets decreases by 8.20 dB and 4.36 dB, respectively. Additionally, when the water-spraying density becomes twice of the designed value, the sound pressure level of water-splashing noise all increases by 3.01 dB for the cooling towers of 300 MW, 600 MW and 1000 MW units. Finally, under the partition water distribution patterns, the change of the sound pressure level is small. For the R s/2 and Rs/3 partition radius (Rs is the radius of water-spraying area), when the water-spraying density ratio between the outer and inner zone increases from 1 to 3, the sound pressure level of water-splashing noise increases by 0.7 dB and 0.3 dB, respectively.

scholarly journals Internal Force on and Deformation of Steel Assembled Supporting Structure of Foundation Pit under Thermal Stress

2021 ◽  
Vol 11 (5) ◽  
pp. 2225
Author(s):  
Fu Wang ◽  
Guijun Shi ◽  
Wenbo Zhai ◽  
Bin Li ◽  
Chao Zhang ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Bending Moment ◽  
High Strength ◽  
Element Model ◽  
Internal Force ◽  
Foundation Pit ◽  
Dimensional Finite Element ◽  
Influence Of Temperature On ◽  
Scale Experiment ◽  
Three Dimensional Finite Element

The steel assembled support structure of a foundation pit can be assembled easily with high strength and recycling value. Steel’s performance is significantly affected by the surrounding temperature due to its temperature sensitivity. Here, a full-scale experiment was conducted to study the influence of temperature on the internal force and deformation of supporting structures, and a three-dimensional finite element model was established for comparative analysis. The test results showed that under the temperature effect, the deformation of the central retaining pile was composed of rigid rotation and flexural deformation, while the adjacent pile of central retaining pile only experienced flexural deformation. The stress on the retaining pile crown changed little, while more stress accumulated at the bottom. Compared with the crown beam and waist beam 2, the stress on waist beam 1 was significantly affected by the temperature and increased by about 0.70 MPa/°C. Meanwhile, the stress of the rigid panel was greatly affected by the temperature, increasing 78% and 82% when the temperature increased by 15 °C on rigid panel 1 and rigid panel 2, respectively. The comparative simulation results indicated that the bending moment and shear strength of pile 1 were markedly affected by the temperature, but pile 2 and pile 3 were basically stable. Lastly, as the temperature varied, waist beam 2 had the largest change in the deflection, followed by waist beam 1; the crown beam experienced the smallest change in the deflection.

Character Analysis of Balance and Imbalance of Varying Rigidity of Rigid Pile Composite Foundation under Seismic Load

2014 ◽  
Vol 1065-1069 ◽  
pp. 19-22
Author(s):  
Zhen Feng Wang ◽  
Ke Sheng Ma
Keyword(s):  
Finite Element ◽  
Bending Moment ◽  
Horizontal Displacement ◽  
Element Model ◽  
Composite Foundation ◽  
Seismic Load ◽  
Seismic Loads ◽  
Element Analysis ◽  
Rigid Pile ◽  
Rigid Pile Composite Foundation

Based on ABAQUS finite element analysis software simulation, the finite element model for dynamic analysis of rigid pile composite foundation and superstructure interaction system is established, which selects the two kinds of models, by simulating the soil dynamic constitutive model, selecting appropriate artificial boundary.The influence of rigid pile composite foundation on balance and imbalance of varying rigidity is analyzed under seismic loads. The result shows that the maximum bending moment and the horizontal displacement of the long pile is much greater than that of the short pile under seismic loads, the long pile of bending moment is larger in the position of stiffness change. By constrast, under the same economic condition, the aseismic performance of of rigid pile composite foundation on balance of varying rigidity is better than that of rigid pile composite foundation on imbalance of varying rigidity.

Integrity Assessment of Damaged Flexible Pipe Cross-Sections

2014 ◽  
Author(s):  
Guomin Ji ◽  
Bernt J. Leira ◽  
Svein Sævik ◽  
Frank Klæbo ◽  
Gunnar Axelsson ◽  
...  
Keyword(s):  
Cross Sections ◽  
Three Dimensional ◽  
Element Model ◽  
Computer Code ◽  
Flexible Pipe ◽  
Dynamic Stresses ◽  
Integrity Assessment ◽  
Residual Capacity ◽  
Nonlinear Finite Element Model

This paper presents results from a case study performed to evaluate the residual capacity of a 6″ flexible pipe when exposed to corrosion damages in the tensile armour. A three-dimensional nonlinear finite element model was developed using the computer code MARC to evaluate the increase in mean and dynamic stresses for a given number of damaged inner tensile armor wires. The study also includes the effect of these damages with respect to the associated stresses in the pressure spiral. Furthermore, the implications of a sequence of wire failures with respect to the accumulated time until cross-section failure in a probabilistic sense are addressed.

scholarly journals Numerical aspects for efficient welding computational mechanics

2014 ◽  
Vol 18 (suppl.1) ◽  
pp. 139-148
Author(s):  
Tarek Aburuga ◽  
Aleksandar Sedmak ◽  
Zoran Radakovic
Keyword(s):  
Residual Stresses ◽  
Three Dimensional ◽  
Shell Element ◽  
Element Model ◽  
Mechanical Analysis ◽  
Tensile Test Specimen ◽  
Integrity Assessment ◽  
Mass Scaling ◽  
Three Dimensional Models ◽  
Thermal Mechanical Analysis

The effect of the residual stresses and strains is one of the most important parameter in the structure integrity assessment. A finite element model is constructed in order to simulate the multi passes mismatched submerged arc welding SAW which used in the welded tensile test specimen. Sequentially coupled thermal mechanical analysis is done by using ABAQUS software for calculating the residual stresses and distortion due to welding. In this work, three main issues were studied in order to reduce the time consuming during welding simulation which is the major problem in the computational welding mechanics (CWM). The first issue is dimensionality of the problem. Both two- and three-dimensional models are constructed for the same analysis type, shell element for two dimension simulation shows good performance comparing with brick element. The conventional method to calculate residual stress is by using implicit scheme that because of the welding and cooling time is relatively high. In this work, the author shows that it could use the explicit scheme with the mass scaling technique, and time consuming during the analysis will be reduced very efficiently. By using this new technique, it will be possible to simulate relatively large three dimensional structures.

Sign in / Sign up

Export Citation Format

Share Document