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time to failure prediction and model of Beishan granite under true triaxial stresses

MECHANICS OF time-DEPENDENT MATERIALS 2025年第1期29卷 1-22页

作者： Jiang, Mengfei Xue, Jiachao Zhao, Jun Northeastern Univ Key Lab Minist Educ Safe Min Deep Met Mines Shenyang 110819 Peoples R China Northeastern Univ Key Lab Liaoning Prov Deep Engn & Intelligent Tech Shenyang 110819 Peoples R China

The characteristics of creep deformation and time to failure of deep hard rock are important for predict time-dependent disasters. Based on the short-term compression and long-term single-stage creep tests under true triaxial stresses, the characteristics of creep deformation and time to failure of Beishan granite subjected to different intermediate principal stress (sigma 2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sigma _time to failure$\end{document}) and deviatoric stress (sigma 1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sigma _time to failure$\end{document}-sigma 3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sigma _time to failure$\end{document}) were studied. The prediction formula of time to failure was established for hard rock, considering the effect of sigma 2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sigma _time to failure$\end{document}. The test results show that the time to failure of rock samples increases with the decrease of the stress-strength ratio (SSR = (sigma 1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\sigma _time to failure$\end{document}-sigma 3\documentclass[12pt]{minimal} \usepackage

关键词： True triaxial creep tests Small deformation time to failure Creep model

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time to failure prediction of rotating machinery using dynamic feature extraction and gaussian process regression

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2024年第5-6期130卷 2969-2984页

作者： Lee, Wo Jae Sutherland, John W. Purdue Univ Lab Sustainable Mfg Environm & Ecol Engn 500 Cent Dr W Lafayette IN 47907 USA

Recent advances in sensor technology and computing capabilities have enabled the creation of data-driven models that can support real-time decision making. Such a decision aid can allow for predictive maintenance (PdM) to be undertaken on a much greater scale in manufacturing plants. PdM includes data-driven prognostics and health management (PHM). A key element in developing prognostic models involves the acquisition of high-quality data, traditionally achieved through feature extraction methods to distill meaningful insights from extensive and noisy datasets. However, such methods may not handle noisy data well or address measurement errors adequately, potentially resulting in extracted features that inadequately represent the degradation process as a machine approaches failure or fault. Also, effects of sensor types on the feature extraction and prediction model have not been much explored yet. To overcome this limitation, we proposed a solution which involves dynamic feature extraction where a statistical penalty is introduced to mitigate the influence of noisy statistical features within a monotonic trend. Subsequently, the features extracted using this method are utilized to construct a health indicator (HI). Leveraging historical HI values, a probabilistic regression model may be used to forecast the time to failure (TTF) of rotating machinery with uncertainty propagation. To validate the proposed method, acceleration data were collected from rotating machinery for several run-to-failure cases. The proposed method is demonstrated to provide excellent forecasts of TTF for both accelerometer types.

关键词： time to failure Dynamic feature extraction Gaussian process Uncertainty quantification Rotating machinery

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time to failure Prediction on a Printed Circuit Board Surface Under Humidity Using Probabilistic Analysis

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JOURNAL OF ELECTRONIC MATERIALS 2022年第8期51卷 4388-4406页

作者： Bahrebar, Sajjad Ambat, Rajan Tech Univ Denmark Sect Mat & Surface Engn Ctr Elect Corros Dept Mech Engn DK-2800 Lyngby Denmark

This paper presents the probabilistic study of time to failure (TTF), which is caused by combinations of various important controllable factors on a printed circuit board (PCB) surface under humidity. The study investigated the impact of four changeable factors including pitch distance, temperature, contamination, and voltage, each at three levels upon the surface insulation resistance test boards. Constant 98% relative humidity with adipic acid as contamination related to flux residue was used for a 20-h parametric experiment. Two main states were considered on the whole output current measurements: the stable part before the short transition phase and the unstable part after due to electrochemical migration (ECM) on the PCB surface. Leakage current (LC) in the first state and TTF at the beginning of the second stage was measured with five replications for each condition as the predictive indicator in all models. The trend of LC and TTF was also investigated on three levels of each factor. In addition, probabilistic distribution analysis using fitted Weibull distribution, multivariate regression analysis, and the classification and regression tree (CART) analysis were used to predict the probability of TTF and failure risk prediction on the PCB surface. All the prediction models had an acceptable prediction of TTF at diverse accuracy levels, according to changing factors/levels. Nevertheless, the multivariate regression analysis had the best prediction, highest R-2, and lowest error compared to the other models.

关键词： Probabilistic analysis prediction model probability of failure PCB surface time to failure

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Supervisory control to maximize mean time to failure in discrete event systems

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DISCRETE EVENT DYNAMIC SYSTEMS-THEORY AND APPLICATIONS 2023年第2期33卷 105-127页

作者： Lin, Feng Wang, Caisheng Nazari, Masoud H. H. Li, Wenyuan Wayne State Univ Dept Elect & Comp Engn Detroit MI 48202 USA Chongqing Univ Sch Elect Engn Chongqing 400044 Peoples R China

In this paper, we investigate the use of supervisory control to maximize mean time to failure in a discrete event system framework. A complex engineering system is modeled as a discrete event system. Some of the states of the system are essential to the functionality of the system and are called required states. Some other states represent failures in the system and are called failure states. The control objective is to maximize the mean time to failure (MTTF) while allowing the system to visit all required states. The control is achieved by a supervisor that disables some controllable events based on monitoring the observable events as in classical supervisory control. To design such a supervisor, the MTTF of a supervised system is calculated by converting a discrete event system into a Markov chain having the same MTTF. Based on MTTF, two algorithms are developed that together allow us to design an optimal supervisor. The theoretical results are applied to power systems by investigating the maintenance management of equipment such as transformers.

关键词： Discrete event systems time to failure Supervisory control Markov chain

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An Improved Approach to Estimate the time to failure for Large Oil Tank in Pool-Fire-Induced Domino Effects by Stress failure

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JOURNAL OF failure ANALYSIS AND PREVENTION 2022年第5期22卷 1954-1964页

作者： Zhang, Xiaochun Tang, Mingcong Ren, Fei Li, Xing Xu, Wenbin Guangdong Univ Technol Sch Environm Sci & Engn Guangzhou 510006 Peoples R China China Acad Safety Sci & Technol Beijing Key Lab Metro Fire & Passenger Transporta Beijing 100012 Peoples R China Hunan Inst Humanities Sci & Technol Dept Energy & Mech Engn Loudi 417000 Peoples R China

Accidental pool fire occurring in process industries facilities with flammable liquid storage tank can lead to severe consequence. Accident statistics analyses show that fire-induced domino effects are the most frequent type of domino effects in oil tank zones. The duration of heat radiation flux released by fire, a time-dependent event, may lead to thermal damage and even the failure of adjacent equipment, whereas the commonly used theory for calculating time to failure (TTF) of fire-induced domino effects will not be available for the tanks with higher volume than 17,500 m(3). Therefore, the purpose of this study is to propose an improved approach for calculating the TTF of large oil tank due to thermal damage and stress failure of target tank wall influenced by heat radiation flux, providing a supplement for the commonly used theory. The proposed approach provides a new perspective to determine the TTF of fire-induced domino effects for target tanks.

关键词： Fire-induced domino effects time to failure failure temperature Allowable stress Analytical solution

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A comprehensive review of influential factors and predictive techniques of time to failure for sewer pipes

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TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY 2025年 157卷

作者： Yang, Jingchao Zayed, Tarek Arimiyaw, Dramani Xiao, Rui Hong Kong Polytech Univ Dept Bldg & Real Estate kowloon Hong Kong Peoples R China McGill Univ Dept Civil Engn Montreal PQ H3A 0C3 Canada

Sewer pipes are vital to urban infrastructure, playing a crucial role in environmental protection and enhancing urban resilience. Their failure results in significant environmental damage and asset management costs. Therefore, employing proactive prediction and timely interventions is critical to mitigate these effects. This review systematically scrutinizes literature from 2000 to 2024, employing scientometric analysis, and systematic review. It aims to pinpoint the factors influencing sewer pipe longevity, evaluate the predictive tools available for forecasting failure time, and identify research gaps as well as areas insufficiently explored by existing studies. The scientometric analysis suggests a growing focus on sewer pipe failure. Systematic review findings reveal a multifaceted understanding of the factors influencing sewer pipe durability, with some well-established and others contentious, leading to ongoing debates. Additionally, the review reveals that predictive models for sewer pipe lifespan are still in the early stages, focusing primarily on concrete and PVC pipes. The insights from this research help illuminate the failure mechanisms of sewer pipes and aid in the advancement of predictive maintenance approaches. Such advancements are essential for improving hazard detection and optimizing resource management within urban sewer networks.

关键词： Sewer pipe Pipe failure failure factors time to failure Predictive techniques Systematic review Scientometric review

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Investigation about the effect of the voltage profile on RPDIV and time to failure for insulation materials subjected to impulsive stress conditions

Investigation about the effect of the voltage profile on RPD...

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IEEE Electrical Insulation Conference (EIC)

作者： Caprara, Andrea Ciotti, Giacomo Techimp Altanova Grp Srl Res & Dev Zola Predosa Italy

ISBN: (数字)9781665480239

ISBN: (纸本)9781665480239

When studying the performances of the insulation systems subjected to impulsive stress conditions, the Repetitive Partial Discharge Inception Voltage (RPDIV) and the time-To-failure (TTF) are key parameters for the evaluation of the electric strength and endurance respectively. The current research aims at investigating how the characteristics of the stress voltage profile - e.g. rise time, impulse repetition rate, voltage magnitude - can affect the inception of the PD phenomena and the degradation rate of the insulating material properties. The results of both the RPDIV and TTF tests, performed with different voltage characteristics, will be reported. To keep the variability of the results to a minimum, the tests were carried out on Twisted Pairs (TP) of enameled copper wires at constant ambient temperature and humidity. Under those simple test conditions, the focus was on the effects of the voltage profile. The results of the accelerated life tests showed the behavior of the dielectric parameters in relation to the selected characteristics of the stress voltage applied. The paper discusses the correlation between the TTF, the voltage amplitude, and repetition rate highlighting how, in the different test conditions, these parameters play a major role in the degradation rate of the insulating material under investigation. Finally, an attempt at describing the life model of the TPs through a quadratic polynomial expression referred to voltage level and repetition rate is discussed.

关键词： RPDIV time to failure accelerated hfe tests partial discharges impulsive testing

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Calculation of 3D displacement and time to failure of an earth dam using DIC analysis of hillshade images derived from high temporal resolution point cloud data

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LANDSLIDES 2020年第3期17卷 499-515页

作者： Berg, Nancy Hori, Toshikazu Take, W. Andy Queen′s Univ Dept Civil Engn Kingston ON K7L 3N6 Canada Natl Inst Rural Engn Dept Geotechn Hydraul Engn Kannondai 2-1-6 Tsukuba Shi Ibaraki Japan

Point cloud data capturing land surface elevation at two instants in time are commonly used to detect landslides occurrence. In this paper, it is hypothesised that this same point cloud data has the potential to yield much more valuable quantitative information regarding landslide behaviour, including the direction, magnitude, and rate of surface displacement. Given point cloud data contains roughness information, shaded projections (hillshade images) of the slope at two or more instants in time can be processed using digital image correlation (DIC) to track displacement in the plane of the projection. If multiple view angles are used to generate the hill shade images, 3D surface displacements of the landslide surface should theoretically be resolved. Furthermore, if point clouds are generated with sufficiently high temporal resolution, it should be possible to estimate the time to failure. The objective of this paper is to test this hypothesis using point clouds generated at high temporal resolution using digital images of a 3.5 m high earth dam field experiment brought to failure under high reservoir water conditions and an extreme rainfall event. This experiment indicates that the proposed method was successful in generating 3D displacement estimates within 2 cm of collected total station data and an estimated time to failure was within four minutes of the observed slope failure.

关键词： Deformation montoring Remote sensing Photogrammetry time to failure Digital image correlation

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Investigation of critical factors effect to predict leakage current and time to failure due to ECM on PCB under humidity

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MICROELECTRONICS RELIABILITY 2021年 127卷 114418-114418页

作者： Bahrebar, Sajjad Ambat, Rajan Tech Univ Denmark Dept Mech Engn Ctr Elect Corros Sect Mat & Surface Engn DK-2800 Lyngby Denmark

Experiments using the Design of Experiment (DoE) methodology were carried out to investigate the effects of pitch distance (P), temperature (T), voltage (V), and contamination (C) on the leak current measured on surface insulation resistance (SIR) test boards. A 24 full factorial design with eight replications was performed, and the response was measured continuously over a 20 hour period for each experiment. Current measured over time exhibited a clear pattern of an initial low and stable current, followed by a transition to a much higher current. Microscopic analysis of the boards indicates that the transition is due to dendrite formation due to electrochemical migration (ECM). The time at the start of this transition phase was identified as the time to failure (TTF) for each experiment. Leakage current (LC) was also calculated as the mean current prior to failure. Analysis of Variance methods were used to model both TTF and LC. Both TTF and LC were found to be significantly affected by P, T, and C. However, the effect of V was found to be significant only for TTF. The general current behavior over the prolonged experimental period and the resulting statistical models give new insight into the failure process related to ECM.

关键词： Design of Experiment Full factorial design Leakage current time to failure PCB surface

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A time to failure evaluation of AlGaN/GaN HEMT transistors for RF applications

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e-Prime - Advances in Electrical Engineering, Electronics and Energy 2022年 2卷

作者： Latry, Olivier Moultif, Niemat Joubert, Eric Ndiaye, Mohamed Groupe de Physique des Matériaux Normandie Université UNIROUEN INSA Rouen CNRS UMR 6634 Rouen 76000 France CEVAA Technopole du Madrillet Saint Etienne du Rouvray 76800 France

This paper reports an evaluation of time to failure (TTF) of GaN transistors for 5G and RADAR applications. The TTF on Arrhenius curves are extrapolated from performed RF pulsed life tests with different input powers and duty cycles. The paper explains the temperature estimation method used in this study for operating conditions of the aging tests. A degradation mechanism of surface pitting is extrapolated from previous works. With our experiments, tests can show that the supposed scaling DC to RF life tests could be now extended for duty cycles. The high reliability of HEMT AlGaN/GaN on RF pulsed operating conditions is shown for a power bar of RF transistors. © 2022

关键词： 5G AlGaN/GaN High Electron Mobility Transistors HEMT Radar time to failure

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