Development and Validation of a Pipeline Buckle and Wrinkle Assessment Model

2004 ◽  
Author(s):  
A. Dinovitzer ◽  
A. Fredj ◽  
R. Lazor ◽  
R. Doblanko
Keyword(s):  
Service Life ◽  
Model Development ◽  
Development Project ◽  
Assessment Model ◽  
Fe Model ◽  
Loading Frequency ◽  
Pipe Segment ◽  
Maintenance Requirements ◽  
Development And Validation ◽  
Further Development

Inspection has revealed pipeline buckles and wrinkles promoted by thermal loads, differential settlement, slope movement and other pipe-soil interaction modes, as well as, cold field bends during construction. While all agree that pipeline wrinkles are undesirable, the urgency of their repair is not commonly understood. In general, it is accepted that the onset of wrinkling does not result in a loss of integrity because pipeline steels are adequately ductile to support large monotonic strains. It is also known that loading is displacement-controlled, thus applied load relief occurs during wrinkle formation. Although failure can occur with only a few strain reversals, the low loading frequency provides time to react. This paper will describe the steps and tools required to define the maintenance requirements for a pipeline wrinkle or to evaluate the effectiveness of remediation techniques. The paper will focus on the results of a preliminary wrinkle model development project aimed at assembling a practical technique capable of predicting the service life of a buckled or wrinkled pipe segment. The LS-DYNA non-linear finite element (FE)-based numerical wrinkle and buckle formation and growth model, developed at BMT Fleet Technology Limited, will be described along with its validation through comparison with full-scale trials and existing design criteria. The paper also discusses the use of the FE model predicted through-life wrinkle behavior to estimate the wrinkle service life and describe the way forward for the further development and implementation of this approach.

scholarly journals A Pipeline Dent Assessment Model Considering Localised Effects

2000 ◽  
Author(s):  
A. Dinovitzer ◽  
A. Bhatia ◽  
R. Walker ◽  
R. Lazor
Keyword(s):  
Service Life ◽  
Pipe Wall ◽  
Element Model ◽  
Assessment Model ◽  
Metal Loss ◽  
Concentration Effects ◽  
Pipe Segment ◽  
Weld Toe ◽  
Pipeline Design ◽  
Weld Seams

The Canadian Pipeline Design Standard (CSA Z662) [1] requires the repair of smooth dents with depths exceeding 6% of the pipeline’s outside diameter. This limit on dent depth is reduced in the presence of additional localised effects such as pipe wall gouges, corrosion or planar flaws. Furthermore, it has been observed that pipe wall metal loss, planar flaws and weld seam interaction with dents can significantly reduce the service life of a dented pipe segment. A previously developed pipeline dent assessment model, based on the actual dent profile and in-service pressure history applied to non-linear pipe finite element model with a fracture mechanics crack growth algorithm, has been used to explore the consequences of these localised effects. The effects of corrosion (uniform or local pitting), weld seams (including their weld toe stress concentration effects and residual stress fields), planar flaws (cracks) and gouges on the service life of a dent are reviewed in this investigation. The performance of the model is demonstrated based on its agreement with field observations. The dent assessment model application and validation processes has indicated that the model presented here can be reliably used to predict the service life of dented pipelines in the presence of various localised effects.

Lateral Side Impact Crash Simulation of Restrained 3 Year Old Child

2014 ◽  
Vol 663 ◽  
pp. 590-595 ◽  
Author(s):  
S. Shasthri ◽  
Qasim H. Shah ◽  
V. Kausalyah ◽  
Moumen M. Idres ◽  
Kassim A. Abdullah ◽  
...  
Keyword(s):  
Motor Vehicle ◽  
Model Development ◽  
Developed Countries ◽  
Assessment Model ◽  
Side Impact ◽  
Lateral Side ◽  
Fe Model ◽  
Model Assessment ◽  
Child Fatality ◽  
Injury Mechanisms

Motor vehicle crashes have become the leading cause of death for children in many developed countries and the trend is on the rise in Malaysia. Child anatomy and physiology necessitates a separate restraints system to be implemented during vehicle travel. Although approximately twice as many crashes with a child fatality are frontal compared to lateral, it is shown that side impacts are nearly twice as likely to result in a child fatality as frontal impacts. Due to the complexity and the highly non-linear nature of vehicle crash affecting occupants, much work still remains to be looked into. This is especially so in the study of injury mechanisms towards efforts of improving CRS design as well as vehicle parameters that may offer more effective and robust injury mitigation. The study here presents a methodology which outlines the development and testing of a simulation model where a 3 year old child, restrained in a CRS within a vehicle, is subjected to lateral side impact by a bullet vehicle. A combined environment of both Finite Element as well as Multi-body is used for the model development. A HYBRID III dummy model is used to represent the child while an FE model is used for the CRS model. A hybrid modelling method is utilized for the belt harness system. The model and simulation conditions are set based on the global FMVSS standard. Head injury criterion and Neck injury criterion are primarily considered in the model assessment. Model development as well as validation steps are presented with discussion of the model’s salient features for greater insights in the study of injury mechanisms.

M-Readiness Assessment Model Development and Validation

2020 ◽  
pp. 823-847
Author(s):  
Muhammad Bakhsh ◽  
Amjad Mahmood ◽  
Nazir Ahmed Sangi
Keyword(s):  
Factor Analysis ◽  
New Technology ◽  
Model Development ◽  
Assessment Model ◽  
Assessment Process ◽  
Primary Data ◽  
Readiness Assessment ◽  
Program Of Study ◽  
Learning Institutions ◽  
Development And Validation

It is important for distance learning institutions to be well prepared before designing and implementing any new technology based learning system to justify the investment and minimize failure risk. It can be achieved by systematically assessing the readiness of all stakeholders. This paper first proposes an m-readiness assessment process and subsequently describes different activities required to develop a m-readiness assessment model. The model was validated and applied to measure m-readiness index of Allama Iqbal Open University (AIOU), Pakistan. Primary data (N=612) were collected. Factor analysis was applied. Extracted factors were confirmed with confirmatory factor analysis. Based on the extracted factors, m-readiness index was calculated. Furthermore, m-readiness index association with age, gender, program of study, income, locality and province were also analyzed by applying one way ANOVA and Kruskal Wallis. The results reveal that there is a significant difference in m-readiness with respect to income, locality, age, gender, program of study and province.

AHP-Based Method for Military Defence Project Risk Assessment

2011 ◽  
Vol 90-93 ◽  
pp. 3039-3042
Author(s):  
Bao Hua Liu
Keyword(s):  
Risk Assessment ◽  
Model Development ◽  
Development Project ◽  
Assessment Model ◽  
Risk Assessment Model ◽  
Ahp Method ◽  
Analytic Hierarchy ◽  
Hierarchy Process ◽  
Type Classification

Based on the risk type classification of model development project, the paper used the analytic hierarchy process (AHP) method, established a AHP risk assessment model of development project, and described the risk assessment idea.

Sign in / Sign up

Export Citation Format

Share Document