Failure Case Studies Research Articles

Slope stability analysis of unsaturated colluvial slopes based on case studies of rainfall-induced landslides

Landslides in colluvial soils under rainfall have been identified as a significant problem due to their loose, heterogeneous nature and low shear strength. Evaluation of the stability of colluvial slopes under rainfall conditions is challenging. This study investigated two landslide failure case studies of colluvial soils to understand the failure patterns using finite element (FE) and limit equilibrium (LE) slope stability analysis methods under unsaturated conditions. Transient seepage conditions due to rainfall infiltration and failure were analysed using hydromechanical models. Here, a FE fully coupled hydromechanical model and a sequential coupling of a FE hydrological and LE mechanical model were used to evaluate the failure of variably saturated slopes. Results from the case studies revealed that the failure occurred due to the rise in the groundwater table in both cases. It was evident that there can be significant disparities in the pore water pressure profiles with the fully coupled and sequentially coupled analysis. The dynamic capability of the two models can also affect the interplay between the hydrological and mechanical aspects. When the thickness of the colluvium layer is large, the failure could potentially occur as a deep-seated failure along the boundary of overburden and the bedrock surface due to the large driving force. However, when the thickness is small, failure can occur along the colluvium-weathered rock surface. The outcomes from the study will contribute to mitigate the uncertainty of failure prediction of landslides in colluvial soils.

Liability Mechanisms and Dispute Resolution in Crypto Exchange Contracts: Balancing Code-Based Execution and Legal Enforceability

This paper examines the tension between code-based execution and legal enforceability in smart contracts used by cryptocurrency exchanges. As decentralized finance grows in prominence, there is an increasing need to balance the immutability and automation of blockchain-based agreements with traditional legal protections and dispute resolution mechanisms. We analyze current approaches to liability allocation and conflict resolution in major crypto exchanges, identifying key challenges in harmonizing algorithmic governance with existing contract law. Case studies of recent exchange hacks and failures are used to illustrate the limitations of purely code-based systems. We then propose a hybrid model that preserves the efficiency of automated execution while incorporating safeguards for human intervention in exceptional circumstances. This framework aims to enhance user protections, regulatory compliance, and overall trust in decentralized financial infrastructure. Our findings have implications for exchange operators, regulators, and contract law as it evolves to address blockchain-enabled agreements.

Case Studies – an Indispensable Source of Experience and Knowledge

Owing to the peculiarities of the design environment that structural engineers have to face – an environment where prototypes are designed and erected without intensive and purposeful development and testing – case studies of failures and/or near misses are an indispensable source of experience and knowledge and form the basis for enhancing and updating the set of technical rules and regulations. By discussing actual and historic case studies, the development of the tools and methods of forensic engineering as well as of the findings from these for the design, erection, supervision, inspection and maintenance of civil engineering structures will be addressed. The interface problems, when different parties are involved, are highlighted, and the necessity of establishing a good and reliable co-ordination mechanism is carved out. Because of the increasing fragmentation of the design process, in combination with the use of complex software tools and inevitable pressure of time, often a comprehensive design review process is the last line of defence to avoid incidents due to minor lapses or serious misjudgements.

Profiles of suction stress of layered soils under infiltration conditions and its applications

Suction stress is critical for understanding the hydrological and mechanical behavior of unsaturated soils in construction and engineering. Many soils encountered in these fields exhibit layering due to geological sedimentation or artificial reinforcement. This study establishes the vertical distributions of matric suction and degree of saturation for layered soils under one-dimensional (1D) steady-state seepage, using the Darcy law and constitutive relationships of unsaturated soils. A closed-form suction stress is derived for an arbitrary number of layers and soil types. Hypothetical layered soils with varying hydraulic properties at four infiltration rates are assessed. Results show that soil stratification affects the suction stress profiles, with the impact depending on infiltration rates, soil configuration, and layer thickness. Abrupt variations in suction stress occur at most layered interfaces due to differences in permeability between adjacent layers. The suction stress profiles can be used to evaluate the earth pressure and stability of layered slopes under seepage conditions. Several case studies of multi-layered slope failures in Southern Italy are presented to demonstrate the suitability of the proposed framework for evaluating the stability of layered slopes under rainfall conditions.

Design to Failure: What Went Wrong?

Failures resulted from a lack of awareness of the dangers involved, a lack of competent geotechnical engineering engagement, poor communication, and a tendency to invest insufficient resources to complete a thorough design. Various factors, including changes in the water table, progressive soil erosion, soil heterogeneity, excavation activities, soil liquefaction, and natural disasters such as earthquakes and landslides, can cause geotechnical failures. This demonstrates the need for geotechnical engineers to have the necessary knowledge and skills to build safe structures with a low risk of geotechnical failure. Prediction and anticipation are the arts of geotechnical design rather than a comprehensive quantitative analysis. As a result, this paper will offer various case studies of geotechnical failures to provide recommendations.

SAGBO on Inner and Outer Surface of Large Alloy 800H Pipe

Abstract One of the objectives of this series of case studies presented in section Failure Analysis of Practical Metallography is to educate colleagues who are new in the field, to inform them about failure mechanisms, not least about the rarer, more exotic ones and about metallurgical causes of failure that were utterly unexpected to occur in the particular failure case studies presented here. The subject of this contribution is a failure mechanism called Strain-assisted Grain Boundary Oxidation (SAGBO). This failure mechanism is not rare at all in hot-going nickel-base components in the aerospace industries. However, SAGBO was certainly unexpected to occur in large pipes that remained well below 400 °C in service.

A Bayesian approach to assess under-deposit corrosion in oil and gas pipelines

Under-deposit corrosion (UDC) and microbiologically influenced corrosion under deposits (UD-MIC) have increasingly been identified as severe forms of localized corrosion threatening the integrity of pipelines. This work utilizes a knowledge-based, semi-quantitative Bayesian approach to capture UDC and UD-MIC susceptibility and severity. This article proposed a Bayesian Network framework to study susceptibility to UDC and UDC corrosion rate. The effective corrosion rate is introduced as a measure to combine the susceptibility and corrosion rate. This measure could identify high-risk locations by assessing the probable corrosion rate while highlighting the pipeline's vulnerability to deposit settlement. Four case studies of pipeline failures due to UDC illustrate the framework's validity. A case study for a sweet gas pipeline is adapted to explore the model's robustness in assessing cases with low probabilities of UDC occurrence. The gas pipeline data, the corrosion key performance indicators spanning six years, general information on the pipeline, and the Bayesian network are made publicly available through a repository.

The journey of business transformation: unfreeze, change and refreeze – a multiple case study

PurposeThe purpose of the study is to identify which factors facilitate and hinder change management in the business strategy execution journey and contribute to its transformation.Design/methodology/approachCompanies that have implemented organizational transformation projects, as an adaptive response to their survival, were studied. The authors chose to work with three companies that went through strong changes in the period between 2014 and 2019. A total of 12 professionals were interviewed, encompassing top management and team members.FindingsCases were described, and the learning from them culminated in the recommendation of six managerial propositions, which should guide change agents in the planning and execution of their business transformation journeys.Research limitations/implicationsThe findings were observed in the three case studies that implemented change management strategies. Failure case studies were not considered, which could present other managerial propositions.Originality/valueThe results of the article highlight the importance of coalition issue before the urgency in the organizational change model and also the importance of institutionalization along the change journey. As a managerial contribution is the model called “framework of the journey of execution and transformation of corporate strategy”, which serves as guidance for executives and agents of change in organizations.

Epic product fails of history

When we first think of failure, we often go to our own personal stories. Sometimes, however, those failures are brought into the public view. As a reminder that even famous companies are made up of fallible people, the following are some short case studies of epic product failures. For now, we’ll focus on products and services because they’re easier to relate to. You might have even held them in your hand and thought to yourself, “This thing is dumb,” or “I would not make that same mistake.”

Consideration of a Tack Coat Bond Strength Test to Minimize the Potential for Slippage Failures on Flexible Airfield Pavements

Slippage failures on flexible pavements are a potential problem for airports given the large wheel loads and high tire pressures of modern aircraft. While not common, when slippage failures do occur the impact can be significant on flexible pavement performance. This paper has three components: (1) case studies of slippage failures that have occurred on airfield pavements; (2) a literature review of relevant interlayer bond strength test procedures; and (3) the results of an analytical, field, and laboratory research investigation. Component (3) was conducted to assess the suitability of interface bond strength tests to evaluate the sufficiency of interlayer bond strength between lifts of asphalt pavement, either new construction or an overlay of existing pavement. The analytical study found that for a fully bonded pavement (no-slip condition), subgrade strength was the primary factor affecting horizontal stress at the interface followed by wheel load. Field cores were obtained from recently constructed asphalt pavements and brought to the laboratory for monotonic direct shear testing to determine bond strength as well as monotonic indirect tensile testing to determine mixture strength. Testing was conducted at 77°F (25°C) and 136°F (58°C). Results showed better repeatability at room temperature with similar relative performance ranking to the critical case high temperature test. Bond strength was influenced by in-place mixture density. Overall, the bond strength test method was practicable for use in field laboratories for acceptance testing.

Identifying and interpreting government successes: An assessment tool for classroom use

Journalists, politicians, watchdog institutions, and public administration scholars devote considerable energy to identifying and dissecting failures in government. Studies and case-studies of policy, organizational, and institutional failures in the public sector figure prominently in public administration curriculums and classrooms. Such a focus on failures provides students with cautionary tales and theoretical tools for understanding how things can go badly wrong. However, students are provided with less insights and tools when it comes to identifying and understanding instances of success. To address this imbalance, this article offers students a framework to systematically identify, comprehensively assess and carefully interpret instances of successful public governance. The three-stage design of the funnel introduces students to relevant debates and literatures about meaningful public outcomes, the prudent use of public power, and the ability to sustain performance over time. The articles also discuss how this framework can be used effectively in classroom settings, helping teachers to stimulate reflection on the key challenges of assessing and learning from successes.

Engineering judgement in undergraduate structural design education: enhancing learning with failure case studies

ABSTRACT Universities face the challenge of developing undergraduate structural engineering students' design judgement. This study evaluates whether introducing ‘learning from failure', centralised around ‘real-world' case studies, serves to facilitate the development of engineering judgement in structural design. The study identifies the use of three characteristics of engineering judgement: diagnostic, inductive, and interpretive in the work of the first-year undergraduate structural design students. Thematic analysis, combined with a constant comparison method and the rigour of inter-researcher reliability, was used to develop coding and mapping to evaluate students' work. The majority of students correctly applied diagnostic engineering judgement to the definition of a problem for a failure case study; and displayed the inductive aspect of judgement. Students' interpretive understanding embraced multi-faceted considerations, with engineering practice, complexity in causality, and learning from history being dominant. Introducing case studies deepened students’ enquiry, stimulating the development of a more nuanced understanding of structural engineering judgement.

Towards Model‐based HSI Engineering: A Universal HSI Model for Utility Optimization

AbstractThis article targets designers of tools for developing utility‐critical systems, including safety‐critical, usability‐critical, and productivity‐critical systems, as well as consumer products. Analyses of operational failure case studies indicate that many of them are due to insufficient support for coping with operational complexity. Operational complexity may be defined in terms of exceptional situations. Prior studies indicate the feasibility of reducing the operational complexity by merging theories from various domains with practices employed in various industries. The article presents a semi‐quantitative study of a universal HSI model, consisting of seven layers of generic mini models (GMM) used to cope with exceptions. Following the APA guidelines, the paper has four sections: introduction, method, results, and discussion.

DELAY RISK ASSESSMENT IN CRUSHER SYSTEM CONSTRUCTION AT PT FREEPORT INDONESIA UNDERGROUND MINE

The construction of a crusher system is a very important sequence in the underground mining stage. Therefore, the delays in completing construction will have a negative effect on production achievement. Of the three crusher systems with a capacity of around 2,500 tons per hour that have been completed to support the development of a new underground mine at PT Freeport Indonesia (PTFI), two of them have experienced a delay in completion of more than one month while the remaining one was completed faster. This study aims to assess the risk of delays in the construction of a crusher system in PTFI’s underground mine. The risk of delay was identified and registered from the history of the construction reports of the three previous crusher systems. Then the opinions of 35 selected experts are collected to provide an assessment on four scales of both consequences and likelihood scores. This expert assessment is used for risk analysis to determine the severity level of each risk. The result of this study identified 79 risks of delay in the construction of a crusher system in PTFI’s underground mine which can be grouped into five categories: 16 risks related to work area, 8 risks related to construction drawing, 22 risks related to materials, 3 risks related to administration, and 30 risks related to resources. From the results of risk analysis and evaluation, it was found that 17 risks of high severity delays required risk treatment: 1 risk in the work area, 11 risks to material, and 5 risks to resources. In very specific projects such as the construction of a crusher system in a remote underground mine, the risks related to materials and resources management are of high severity impact for project delays. Keywords: construction delay analysis, construction failure case studies, construction risk assessment, project risk management

The lack of failure reports in published psychotherapy case studies: Implications for dis-‘illusioning’ of research and practice

ABSTRACT Analysis of single cases represents an essential strategy for developing our understanding of paradoxical outcome and illusory mental health. Based on findings from both practice-based and randomized controlled outcome studies, 35-40% of clients fail to improve over the course of psychotherapy.We examined the prevalence of failure cases in the Single Case Archive, a database that includes more than 3000 psychotherapy case studies from a variety of ISI-ranked journals. We found that only 4% of these studies describe any form of failure in treatment. Thematic analysis of the titles and abstracts of failure case studies revealed that the majority did not focus on investigating the nature or meaning of failure but were primarily interested in other theoretical and practical matters. We propose a number of explanations for this apparent publication bias in case study research and discuss implications for further research.

The detrimental effects of water on electronic devices

Water in its various forms can affect the performance and reliability of today's electronics in unique ways. This paper discusses the forms of water and the degradation effect of water on electronics, identifies the types of failure mechanisms in electronics induced by liquid and vapor phase water, presents case studies of water-related failures, and provides recommendations for preventing water-imposed degradation in electronics. Test methods and standards based on different forms of water and specific applications of electronics are also presented.

Case studies of operational failures of vanadium redox flow battery stacks, diagnoses and remedial actions

Vanadium redox flow batteries show enormous scope in large-scale storage and load balancing of energy from intermittent renewable energy sources. Although a number of studies have been published in the last two decades on various aspects of these flow batteries, very few have reported on practical aspects such as design considerations, guidelines and operational failures. Adequate attention to engineering aspects, failure detection and diagnosis are essential for smooth operation of the flow batteries. This paper discusses a few case studies of operational failures during the design and development of kilowatt-scale flow batteries together with their diagnoses and remedial actions. Specifically, failures in the membrane, tubing network and state of electrode have been discussed and suitable recommendations and guidelines are given to avoid these. In each case, rectification of the malfunction was confirmed through results obtained using electrochemical testing protocols established in previous studies. Based on these experiences, good practice guidelines have been recommended for proper fabrication, assembly and characterization of stacks.

Analysis of Sand-Control-Installation Failures Provides Insights, Paths Forward

This article, written by JPT Technology Editor Judy Feder, contains highlights of paper SPE 199251, “Understanding Sand-Control-Installation Failures,” by Raymond Tibbles, SPE, Kesavan Govinathan, SPE, and Ian Mickelburgh, SPE, DuneFront, et al., prepared for the 2020 SPE International Conference and Exhibition on Formation Damage Control, 19-21 February, Lafayette, Louisiana. The paper has not been peer reviewed. Sand-control-installation failures range from minor issues that can be remedied easily to catastrophic events that put the entire well and investment at risk. The complete paper introduces several case studies of such failures and details the investigative process and techniques used to identify root causes. A commercial software tool incorporating data-analysis techniques and a methodical evaluation work flow were used to understand the cause of the failures and determine how they can be prevented in future operations. Examples include events such as screen and washpipe damage, bridging, hole collapse, and packer-seal failure. Introduction Potential modes of failure tradition ally have been investigated with material- balance calculations and surface-pressure measurements. However, this simple approach is unable to diagnose clearly the specific failure mode and often is insufficiently precise to be conclusive, especially for high-value wells. While surface data provide an overview of the operation, the data are influenced by many factors involving the entire system, making it difficult to differentiate multiple events and locate them in the flow path. Mass-balance calculation is also a rudimentary analysis with many inherent assumptions. Often, estimations of perforation or openhole volumes are inaccurate, location of voids cannot be identified in the event of an incomplete pack, and gravel volume and mass measurements do not help in understanding packing mechanisms. Attempts have been made to develop logging techniques to obtain a clearer picture of the outcome of a gravel pack. While this effort has met with some success in cased holes, it has proved to be difficult to apply in open holes. Regardless, identification of the presence of voids in a gravel pack does not provide a clear explanation of why they formed and how they may be prevented in the future.

Marine Propulsion System Failures—A Review

Failures of marine propulsion components or systems can lead to serious consequences for a vessel, cargo and the people onboard a ship. These consequences can be financial losses, delay in delivery time or a threat to safety of the people onboard. This is why it is necessary to learn about marine propulsion failures in order to prevent worst-case scenarios. This paper aims to provide a review of experimental, analytical and numerical methods used in the failure analysis of ship propulsion systems. In order to achieve that, the main causes and failure mechanisms are described and summarized. Commonly used experimental, numerical and analytical tools for failure analysis are given. Most indicative case studies of ship failures describe where the origin of failure lies in the ship propulsion failures (i.e., shaft lines, crankshaft, bearings, foundations). In order to learn from such failures, a holistic engineering approach is inevitable. This paper tries to give suggestions to improve existing design procedures with a goal of producing more reliable propulsion systems and taking care of operational conditions.

Failure Cases Analysis in Aerospace Field

The major concern in the aviation industry is the flight safety. Although great effort has been put into the development of material and system reliability, the failure cases of fatal accidents still occur nowadays. Due to the complexity of the aviation system and the interaction among the failure components, it is difficult to do the failure analysis of the related equipment. This study focused on surveying the failure cases in aviation, which were extracted from failure analysis journals, including Engineering Failure Analysis and Case studies in Engineering Failure Analysis, in order to obtain the failure sensitive factors or failure sensitive parts. The analytical results showed that among the failure cases the fatigue failure is the largest in number of occurrence. The most failed components are the disk, blade, landing gear, bearing, and fastener. The frequently failed materials are steel, aluminum alloy, superalloy and titanium alloy. Therefore, in order to assure the safety in aviation, more attention should be paid to the fatigue failures.