A New Rupture Prediction Model for Corroded Pipelines Under Combined Loadings

1998 ◽  
Author(s):  
Wei Wang ◽  
Marina Q. Smith ◽  
Carl H. Popelar ◽  
James A. Maple
Keyword(s):  
Prediction Model ◽  
Thermal Loading ◽  
Axial Loading ◽  
Full Scale ◽  
Element Analysis ◽  
Strain Limit ◽  
Rupture Pressure ◽  
Scale Test ◽  
Full Scale Tests

It is commonly believed that bending and other secondary loading will reduce the rupture pressure of a corroded pipe. This paper shows through theory, full-scale tests and finite element analysis (FEA) that this need not be the case in the field where displacement controlled bending and axial loading are induced by differential settlement and axial constraint. Based on this result, a new strain-based rupture prediction model is developed for buried corroded pipes subjected to internal pressure, lateral bending, thermal loading and residual stress. The selection of an appropriate “bulging factor,” the determination of a biaxial strain limit and the treatment of the heat affected zone (HAZ) are also discussed in the paper. The predicted rupture pressures agree well with the full-scale test results.

Determination of the Collapse and Propagation Pressure of Ultra-Deepwater Pipelines

2003 ◽  
Author(s):  
Rita G. Toscano ◽  
Chris M. Timms ◽  
Eduardo N. Dvorkin ◽  
Duane D. DeGeer
Keyword(s):  
Finite Element ◽  
Test Data ◽  
External Pressure ◽  
Full Scale ◽  
Test Program ◽  
Element Analysis ◽  
Line Pipe ◽  
Scale Test ◽  
Analysis Models

In the design of ultra-deepwater steel pipelines, it is important to be able to determine the pipe behaviour while subjected to external pressure and bending. In many cases, the ultra-deepwater lay process, where these high loads exist, governs the structural design of the pipeline. Much work has been performed in this area, and it is generally recognized that there is a lack of test data on full-scale samples of line pipe from which analyses can be accurately benchmarked. This paper presents the results of a nil-scale test program and finite element analyses performed on seamless steel line pipe samples intended for ultra-deepwater applications. The work involved obtaining full-scale test data and further enhancing existing finite element analysis models to accurately predict the collapse and post-collapse response of ultra-deepwater pipelines. The work and results represent a continuing effort aimed at understanding the behaviour of pipes subjected to external pressure and bending, accounting for the numerous variables influencing pipeline collapse, and predicting collapse and post-collapse behaviour with increasing confidence. The test program was performed at C-FER Technologies (C-FER), Canada, with the analyses undertaken by the Center for Industrial Research (CINI), Argentina. The results of this work have demonstrated very good agreement between the finite element predictions and the laboratory observations. This allows increased confidence in using the finite element models to predict collapse and post-collapse behaviour of pipelines subject to external pressure and bending.

scholarly journals Full-Scale Tests for Assessing Blasting-Induced Vibration and Noise

2018 ◽  
Vol 2018 ◽  
pp. 1-14
Author(s):  
Chung-Won Lee ◽  
Jiseong Kim ◽  
Gi-Chun Kang
Keyword(s):  
Noise Level ◽  
Full Scale ◽  
Noise Prediction ◽  
Square Root ◽  
Infrastructure Development ◽  
Full Scale Test ◽  
Noise Levels ◽  
Tunnel Excavation ◽  
Scale Test ◽  
Full Scale Tests

Vibration and noise problems caused by a number of construction processes, specifically blasting for infrastructure development, are becoming important because of their civil appeal. In this study, a square root equation (SRE) with a 95% confidence level was proposed for predicting blasting-induced vibration through full-scale test blasting, and the vibration value predicted from this equation was located between the values predicted from the USBM (US Department of Interior, Bureau of Mines), NOF (Nippon Oil & Fats Co., Ltd.), and MCT (Ministry of Construction and Transportation) equations. Additionally, by comparing the measured noise level at full-scale test blasting with the calculated noise levels from several noise prediction equations, it was determined that the noise level predicted by the ONECRC equation had the best agreement with the measured results. However, in cases where blasting includes tunnel excavation, simultaneous measurement of vibration and noise is required to prevent damage to the surrounding facilities.

Finite element modeling of hexagonal wire reinforced embankment on soft clay

2000 ◽  
Vol 37 (6) ◽  
pp. 1209-1226 ◽  
Author(s):  
D T Bergado ◽  
C Teerawattanasuk ◽  
S Youwai ◽  
P Voottipruex
Keyword(s):  
Finite Element ◽  
Full Scale ◽  
Soil Reinforcement ◽  
Wire Mesh ◽  
Direct Shear ◽  
Full Scale Test ◽  
Element Analysis ◽  
Consolidation Process ◽  
Scale Test ◽  
Test Embankment

A full-scale test embankment was constructed on soft Bangkok clay using hexagonal wire mesh as reinforcement. This paper attempts to simulate the behavior of the full-scale test embankment using the finite element program PLAXIS. The agreement between the finite element results and the field data is quite good. The important considerations for simulating the behavior of the reinforced wall embankment were the method of applying the embankment loading during the construction process, the variation of soil permeability during the consolidation process, and the selection of the appropriate model and properties at the interface between the soil and reinforcement. The increased reinforcement stiffness tends to increase the reinforcement tension and increase the embankment forward rotation. The reinforcement tensions increased with the compression of the underlying soft foundation. The appropriate interface properties between the backfill soil and the hexagonal wire mesh reinforcement corresponding to the interaction mechanism at working stress conditions were dominated by the direct shear mechanism. The direct shear interaction coefficient of 0.9 was used.Key words: soil reinforcement, hexagonal wire mesh, finite element analysis, field embankment.

STUDY ON RETROFIT EFFECTS FOR HORIZONTAL PLANE OF TRADITIONAL WOODEN HOUSES BASED ON FULL-SCALE TEST

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mitsuhiro Miyamoto ◽  
Haruka Okuhiro
Keyword(s):  
Horizontal Plane ◽  
Pushover Analysis ◽  
Full Scale ◽  
Horizontal Shear ◽  
Full Scale Test ◽  
Analysis Model ◽  
Scale Test ◽  
Full Scale Tests ◽  
Static Pushover Analysis ◽  
Good Agreement

In the present study, few studies have focused on the horizontal plane of traditional wooden houses in Japan. This study aims to examine the retrofit effects for the horizontal plane of traditional wooden houses based on full-scale tests. The first part of this paper is devoted to the experimental study performed to determine the structural behavior and characteristics of full-scale roof specimens. A horizontal shear test was conducted to obtain the fracture mode and relationship between the applied load and deformation angle. The second part deals with a static pushover analysis of the full-scale roof specimens. The results between the experimental test and the static pushover analysis are presented and discussed. The analysis model used for the static pushover analysis is proposed; the results were in good agreement with the tests.

Fatigue Resistant Threaded and Coupled Connectors for Deepwater Riser Systems: Design and Performance Evaluation by Analysis and Full Scale Tests

2008 ◽  
Author(s):  
Celine Sches ◽  
Emmanuel Desdoit ◽  
Jacky Massaglia
Keyword(s):  
Performance Evaluation ◽  
Fatigue Cracks ◽  
Systems Design ◽  
High Strength Steels ◽  
Full Scale ◽  
Post Treatment ◽  
Mechanism Analysis ◽  
Element Analysis ◽  
And Performance ◽  
Full Scale Tests

Threaded and Coupled (T&C) riser connectors with High Strength Steels have been developed for deepwater top tensioned riser (TTR) applications up to 10,000ft Water Depth. These developments have been ongoing for a decade, and the resulting solutions are now becoming the standard in the industry. Due to the stringent fatigue requirements involved, new design and performance evaluation methods were needed and have been built over time. In this article, we will demonstrate how these methods were implemented into the standard development process of T&C connectors, with a focus on finite element analysis (FEA) techniques. This process includes full scale tests programs on resonant fatigue frames, statistical post treatment of the resulting data, and fatigue cracks expertise for failure mechanism analysis. These elements are a key for the evaluation of T&C connectors’ fatigue performance and for the determination of influencing parameters, leading to the proper design optimization possibilities. The application of these methods will be illustrated with actual examples on T&C connectors’ recent developments. Namely, we will describe FEA methodologies, testing methods and results post-treatment techniques. We will show how the connectors’ performance is eventually derived after such analysis and test data accumulation. The reader will see that innovative and effective fatigue enhancement techniques have resulted, along with premium fatigue compliant sealing devices. The experience and expertise gained, together with a continuous improvement process of our methods have made T&C riser connectors a viable solution to meet emerging needs within deepwater industry, including xHP-HT, SCR and flow lines.

A new methodology for the assessment of the running resistance of trains without knowing the characteristics of the track: Application to full-scale experimental data

2018 ◽  
Vol 232 (6) ◽  
pp. 1814-1827 ◽  
Author(s):  
Claudio Somaschini ◽  
Tommaso Argentini ◽  
Daniele Rocchi ◽  
Paolo Schito ◽  
Gisella Tomasini
Keyword(s):  
High Speed ◽  
High Capacity ◽  
Full Scale ◽  
Design Stage ◽  
Resistance Force ◽  
Full Scale Test ◽  
High Speed Trains ◽  
Scale Test ◽  
Full Scale Tests ◽  
Resistance Coefficients

The resistance to motion of trains is an essential requisite especially while designing high-speed trains and high-capacity railway lines. The optimisation of friction effects and aerodynamic performance can be done during the design stage of a new train but the actual value of the running resistance can be inferred only by means of full-scale tests during the operation of a train. A CEN standard (EN 14067-4) describes the methodologies for the assessment of the running resistance of railway vehicles starting from full-scale test measurements. According to this standard, the speed-dependent terms of the resistance force have to be determined by means of coasting tests on railway lines, whose characteristics must be well known. Since this is not always possible and small errors on the gradient could lead to major uncertainties in the evaluation of the resistance force, a new method for the estimation of the running resistance coefficients, irrespective of the characteristics of the track is proposed in this paper. The reliability of the method is verified by comparing the results with those obtained from the procedure proposed in the CEN standard. The comparison shows that the new methodology is able to evaluate the resistance coefficients with an accuracy equivalent to that of the other methods but with fewer tests and with a more robust procedure relying on a lesser number of parameters.

scholarly journals Finite Element Analysis and Full-Scale Testing of Locomotive Crashworthy Components

2013 ◽  
Author(s):  
Patricia Llana ◽  
Richard Stringfellow ◽  
Ronald Mayville
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
New Technologies ◽  
Element Model ◽  
Full Scale ◽  
Element Analysis ◽  
Design Concepts ◽  
Dynamic Finite Element Analysis ◽  
Full Scale Tests ◽  
Force Displacement

The Office of Research and Development of the Federal Railroad Administration (FRA) and the Volpe Center are continuing to evaluate new technologies for increasing the safety of passengers and operators in rail equipment. In recognition of the importance of override prevention in train-to-train collisions in which one of the vehicles is a locomotive, and in light of the success of crash energy management technologies in cab car-led passenger trains, the Volpe Center seeks to evaluate the effectiveness of components that could be integrated into the end structure of a locomotive that are specifically designed to mitigate the effects of a collision and, in particular, to prevent override of one of the lead vehicles onto the other. A research program has been conducted to develop, fabricate and test two crashworthy components for the forward end of a locomotive: (1) a deformable anti-climber, and (2) a push-back coupler. Detailed designs for these components were developed, and the performance of each design was evaluated through large deformation dynamic finite element analysis (FEA). Designs for two test articles that could be used to verify the performance of the component designs in full-scale tests were also developed. The two test articles were fabricated and dynamically tested by means of rail car impact in order to verify certain performance characteristics of the two components relative to specific requirements. The tests were successful in demonstrating the effectiveness of the two design concepts. Test results were consistent with finite element model predictions in terms of energy absorption capability, force-displacement behavior and modes of deformation.

Strain Capacity Prediction of Strain-Based Pipelines

2014 ◽  
Author(s):  
Huang Tang ◽  
Doug Fairchild ◽  
Michele Panico ◽  
Justin Crapps ◽  
Wentao Cheng
Keyword(s):  
Damage Mechanics ◽  
Critical Role ◽  
Active Regions ◽  
Full Scale ◽  
Element Analysis ◽  
Strain Capacity ◽  
Fea Model ◽  
Full Scale Tests ◽  
Numerical Program ◽  
Allowable Stress Design

Strain-based design (SBD) is used to complement conventional allowable stress design for pipelines operated in environments with potentially large ground movements such as those found in permafrost and seismically active regions. Reliable and accurate prediction of tensile strain capacity (TSC) plays a critical role in strain-based design. As reported previously over the past 6+ years, a comprehensive experimental and numerical program was undertaken to characterize the TSC of welded pipelines, develop a finite element analysis (FEA) approach and equations capable of predicting TSC, and establish a strain-based engineering critical assessment (SBECA) methodology. The previous FEA model and TSC equations were validated against about 50 full-scale pipe strain capacity tests and are accurate within the validated variable ranges. In the current paper, enhancements of the previous model and equations are described. The enhancements include incorporation of advanced damage mechanics modeling into TSC prediction, development of a new TSC equation, expansion of variable ranges and functionality upgrades. The new model and equation are applicable over larger ranges of material properties and flaw sizes. The new FEA model is also used to establish surface flaw interaction rules for SBD. The new FEA model is validated against more than 40 full-scale non-pressurized and pressurized tests and underpins the development of the new TSC equation. The equation is validated against a total of 93 full-scale tests (FST). In addition to the enhancements, sample applications of the TSC model and equation are presented in the paper, for example, an investigation of the effects on strain capacity of Lüders strain and ductile tearing. Challenges in predicting TSC are also addressed.

Advances in the Railroad Locomotive Crashworthiness

2003 ◽  
Author(s):  
Swamidas Punwani ◽  
Gopal Samavedam ◽  
Steve Kokkins
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Impact Strength ◽  
Full Scale ◽  
Fuel Tank ◽  
Structural Components ◽  
Dynamic Impact ◽  
Element Analysis ◽  
Simulation Results ◽  
Full Scale Tests

The paper describes locomotive and fuel tank crashworthiness research being conducted by the Federal Railroad Administration for improved safety of the locomotive crew under collision scenarios. The research involves static and dynamic impact strength evaluations of locomotive structural components. These evaluations which are based on full scale tests and simulations using finite element analysis are described in this paper. Correlations between the test and simulation results are also presented in some cases.

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