Structural integrity analysis of HDPE pipes for water supplying network

The flywheel of latest coolant pump provides high inertia to ensure a slow decrease in coolant flow to prevent fuel damage after the loss of power. Flywheel comprises a hub, twelve tungsten alloy blocks and a retainer ring shrink-fit assembled on the outer surface of blocks. In the structural integrity analysis, the shrinkage load due to shrink-fit and the centrifugal load due to rotation are considered, so the wall thickness of retainer ring and the magnitude of shrink-fit are key variables. In particular, these variables will change the flywheel running state. This paper considers the influence of these variables, we employ Latin hypercube design to obtain the response surface model and analyze the influence of these variables. Finally we obtain the magnitude of wall thickness of retainer ring and the range of shrink-fit.

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Investigation of Discrepancies in Waterhammer Structural Integrity Analysis Simulation and Actual Vibration Testing

Volume 2: Structural Integrity; Safety and Security; Advanced Applications of Nuclear Technology; Balance of Plant for Nuclear Applications ◽

10.1115/icone17-75100 ◽

2009 ◽

Author(s):

Khalid Chaudhry ◽

Andrei Blahoianu

Keyword(s):

Structural Integrity ◽

Linear Analysis ◽

Relief Valve ◽

Pressure Time ◽

Asme Code ◽

Time Histories ◽

Valve Opening ◽

Simulation Results ◽

Measured Displacement ◽

Integrity Analysis

While verifying the Primary Heat Transport (PHT) piping design for increased waterhammer loads due to sudden relief valve opening, it was discovered that linear piping analysis FEA program, which was relied upon extensively in the past, predicted overly conservative results. By overestimating the piping stresses, the stress results did not satisfy the ASME code, Section III, subsection NB-3652 Equation 9 limits for Level B service loading. During the course of investigation to meet ASME code limits, the licensee carried out a series of controlled actual waterhammer tests on thoroughly instrumented PHT piping and recorded the measured piping displacements. Waterhammer pressure-time histories created from these actual tests were then used as input into the standard linear piping analyses to compare analysis simulation results with the actual measured displacement data. It was observed that the analysis simulation results overestimated the piping displacement results by a large margin, i.e., by a factor of 5. A further insight into the analysis results indicated the presence of a single, the so called “killer” mode of vibration which accounted for nearly all of the PHT piping displacement response to test waterhammer loading. On a hypothetical basis, a restraint was applied in the direction of vibration of the pipe and the linear analysis was repeated. It was discovered that the simulated analytical piping response using a modified restraint had a much better match with the displacement results obtained during the actual test. From this hypothetical restraint application, it was inferred that friction between the supports and the pipe is the key ingredient which dampens the pipe oscillations and hence a lower response during the test than the linear analysis which does not consider the friction between the pipe and its guide support. This paper further investigates the contribution of structural damping, friction effects between the pipe and its supports (use of contact elements), fluid structure interactions and issues related to application of friction to carry out ‘modified’ nonstandard analyses to better predict the piping response to waterhammer transient loading.

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Structural integrity analysis of pipelines with interacting corrosion defects by multiphysics modeling

Engineering Failure Analysis ◽

10.1016/j.engfailanal.2019.01.009 ◽

2019 ◽

Vol 97 ◽

pp. 91-102 ◽

Cited By ~ 2

Author(s):

Elder Soares ◽

Vivianne Marie Bruère ◽

Silvana M.B. Afonso ◽

Ramiro B. Willmersdorf ◽

Paulo R.M. Lyra ◽

...

Keyword(s):

Structural Integrity ◽

Multiphysics Modeling ◽

Corrosion Defects ◽

Integrity Analysis

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A Multilevel Approach for the Cultural Heritage Vulnerability and Strengthening: Application to the Melfi Castle

Buildings ◽

10.3390/buildings10090158 ◽

2020 ◽

Vol 10 (9) ◽

pp. 158

Author(s):

Cristina Cantagallo ◽

Enrico Spacone ◽

Daniele Perrucci ◽

Nicola Liguori ◽

Clara Verazzo

Keyword(s):

Structural Integrity ◽

Seismic Analysis ◽

Pushover Analysis ◽

Historical Analysis ◽

Safety Evaluation ◽

Soil Survey ◽

Seismic Safety ◽

Seismic Safety Evaluation ◽

Cracking Pattern ◽

Integrity Analysis

This study outlines a procedure for the seismic safety evaluation of historical buildings for engineers and architects that commonly work on buildings belonging to cultural and architectural heritage. The procedure is characterized by two interrelated phases: (a) building knowledge acquisition and (b) structural behavior analysis and safety assessment. The seismic safety evaluation strongly depends on the first phase, whose data can be obtained according to a multi-disciplinary approach based on five steps: (1) critical-historical analysis; (2) photographic documentation and geometrical survey; (3) structural identification and material survey; (4) foundation and soil survey; and (5) cracking pattern and structural integrity analysis. The proposed method was applied to the evaluation of the seismic safety of the Castle of Melfi (PZ, Italy). Comprehensive and multi-disciplinary knowledge of this monument greatly facilitated an accurate seismic analysis of this monument, which was conducted both at a local and global level using a linear kinematic analysis and non-linear static (pushover) analysis, respectively.

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Structural integrity analysis of embedded optical fibres in composite structures

Composite Structures ◽

10.1016/s0263-8223(00)00050-7 ◽

1999 ◽

Vol 47 (1-4) ◽

pp. 759-765 ◽

Cited By ~ 32

Author(s):

R. Hadzic ◽

S. John ◽

I. Herszberg

Keyword(s):

Composite Structures ◽

Structural Integrity ◽

Optical Fibres ◽

Integrity Analysis

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Probabilistic Structural Integrity Analysis of Reactor Pressure Vessels During PTS Events

Volume 1: Codes and Standards ◽

10.1115/pvp2012-78836 ◽

2012 ◽

Author(s):

Kunio Onizawa ◽

Koichi Masaki ◽

Jinya Katsuyama

Keyword(s):

Crack Initiation ◽

Structural Integrity ◽

Fracture Probability ◽

Pressure Vessels ◽

Sensitivity Analyses ◽

Conditional Probabilities ◽

Integrity Assessment ◽

Pressurized Thermal Shock ◽

Integrity Analysis ◽

Reactor Pressure

In order to apply a probabilistic fracture mechanics (PFM) analysis to the structural integrity assessment of a reactor pressure vessel (RPV), PFM analysis code has been developed at JAEA. Using the PFM analysis code, PASCAL version 3, the conditional probabilities of crack initiation and fracture for an RPV during pressurized thermal shock events have been analyzed. Sensitivity analyses on some input parameters were performed to clarify the effect on the conditional fracture probability. Comparison between the conditional probabilities and temperature margin (ΔTm) from current deterministic analysis method were made for some model plant conditions of domestic typical old-type RPVs. From the analyses, a good correlation between ΔTm and the conditional probability of crack initiation was obtained.

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