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Highlights • The influence of grounding system in overhead lines failure. • New simulation-based EMTP was developed for sensibility analysis in grounding systems. • A recommendation for national and international standard for limit values for grounding system was proposed. [ABSTRACT FROM AUTHOR]

An important requirement imposed on storage batteries nowadays is to have sufficient capacity. At the same time a high level of availability, reliability and safety is required as well. Our intention is to determine a capacity degradation threshold and the moment the soft failure of a graphite supercapacitor (SC) occurs. If we do not take into account the idle state, the functioning of the supercapacitor might be expressed by charging and discharging processes under different operating conditions given by the allowed extent of SC design. When looking for the degradation threshold and the moment of soft failure occurrence we performed the experimental part of measuring in the climatic chamber. We performed and recorded the processes of SC charges and discharges at different temperatures: 40 °C, 25 °C and −42 °C and at different charging and discharging currents: 2A, 4A, 6A and 8A. The experimental results were used to model mathematically the SC discharge process. Appropriate tools used for SC discharge are diffusion processes. In this case we apply a Wiener process with drift and an Itô process. [ABSTRACT FROM AUTHOR]

The industry of electric cars has been rising significantly in the last few years. This significant growth is impulsed by lithium-ion batteries (LIBs). LIBs are a stable technology that is the largest applied for storing energy systems in several sectors like electric mobility, laptops, and cell phones. However, LIBs are still sensible and must operate under controlled conditions to avoid failures and anomalies that can cause security and performance issues. Therefore, it is crucial to identify the possible failures in the initial stage. In order to help the precocious failure identification, some data-driven have been impulsed by Machine Learning (ML) techniques to diagnose failures as soon as possible. Following this direction, this work presents the application of six classification ML models to identify failures in LIBs. In order to generate the dataset, the main parameters of eight lithium-ion 18650 cells were collected under four different cases of abuse: overcharging (OC), over-discharging (OD), external short-circuit (ESC) and overheating (OH). The confusion matrix and Sensitivity were used to evaluate and compare the models. The work shows that, on average, the models could detect a failure with the Sensitivity greater than 94% for mechanical, electrical, and thermal failures. Furthermore, the RF model had the better performance of all, with the Sensitivity greater than 97%. In conclusion, according to the excellent results, this approach can be used in LIBs to detect failures in the initial stage. Due to the excellent results, the evolution of this study is embedded this study in the vehicle to classify abuses online to reduce the chances of security and performance issues. • Failures in lithium-ion batteries reduce the battery lifetime. • Three groups of failures are present in LIB: mechanical, electrical, and thermal. • Data-driven combined with Machine Learning techniques improve the detection of failures as sooner as possible and in real-time. • Construction of a mini packing of batteries to generate data. • Random Forest was the best model to detect failures in LIB. [ABSTRACT FROM AUTHOR]

Highlights: [•] We present analysis of a failed stainless steel molten salt corrosion experiment. [•] We examine corrosive gas evolution between molten salt and insulation. [•] Corrosive gas leads to the structural failure of the high temperature system. [•] Stainless steel shows heavy attack through vapor fluorination. [Copyright &y& Elsevier]

Highlights: [•] We examine failure criteria for anisotropic material to apply to wood. [•] Hill, Tsai-Hill, Tsai-Wu, Hoffman and Norris failure criteria were studied. [•] Failure envelope curves for two Brazilian wood species were performed. [•] Comparisons with envelopes curves from experimental results were provided. [•] Hoffman criterion presented the best strength evaluation for these wood species. [ABSTRACT FROM AUTHOR]

Highlights: [•] Cumalıkızık traditional timber structures had been built with a holistic design understanding. [•] Faulty repairs by the building owners and new add-ons created significant hazards to the timber structures. [•] Timber beams formed in the stone walls has an important function in the compensation for the tensile stresses. [•] Adobe-filled timber structural system resist the earthquake forces in harmony. [•] The timber joint details solved with the most appropriate methods. [ABSTRACT FROM AUTHOR]

Highlights: [•] Column shear-axial failure does not necessarily constitute structural collapse. [•] A column failure leads to an increasing shear demand in columns above and below. [•] Columns above a failed column become significantly more susceptible to failure. [•] Shear-axial failure of columns over the same column line is not significantly damaging. [•] Axial failure of a column causes an immediate drop in compression of columns above. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the analysis on broken of architectural glass panel subjected to blast loading is investigated. The architectural glass panel breaks up into fragments when it is overloaded by the external blast. The projection velocity and splash distance of glass fragments are very important parameters to establish fragment flight trajectory. In this paper, the fragment projection velocity is formulated based on energy principles, and the flight path is proposed by solving the acceleration equations established according to the variations of motion direction and force direction of the fragment. Explosive tests of architectural glass panel were carried out in the field test site to investigate the pressure loss effect on the projection velocity during the deformation of the panel. Empirical expressions of glass fragment flight trajectory are developed using a combined theoretical and experimental approach, which may be used to estimate the hazard from broken glazing. [Copyright &y& Elsevier]

Abstract: The causes of recent fires in hydrocarbon heaters are discussed in this paper. In particular, failures are chosen for which root causes involve trying to get around existing operational shortcomings by making changes to control, instead of carrying out a proper Root Cause Analysis to identify actual causes of deficiencies. In one case, the heater would extinguish due to the poor characteristics of fuel gas. A restart routine was devised, in which previous purging was avoided. In the other case, turning off one burner would turn off the remaining. Instead of addressing the reason why a burner would turn off, the operator modified gas inlet control so that the remaining burners would remain on. Details are given of the chain of events that led to these failures. It is concluded that heaters should be carefully chosen or designed to meet specific operation requirements. Modifications should be avoided whenever possible and carefully planned, in association with the manufacturer when they are unavoidable. In every case, safety systems should be in accordance with modern safety standards. [Copyright &y& Elsevier]

Abstract: The safety of a population also relies on the safety of the water pipe network systems. Good quality water supplying is required. A failure of these types of systems may have a huge social impact. The theory of vulnerability of water pipe networks intends to give a contribution in this context by tracing the vulnerable parts of the system and, consequently, giving guidance to increase its robustness. This theory is described in brief and supported on three water pipe networks examples. [Copyright &y& Elsevier]

Abstract: In this research, the high failure rate of indigenously produced mould die of an industrial punching machine utilized for the production of cable trays was investigated. This was aimed at discovering the reason(s) for the disparity in the service life of the indigenously produced die as against the imported ones that had longer service life. The failure investigation was carried out utilizing visual examination, microstructural examination, hardness test and chemical composition determination. The analysis show that the short service life of the indigenous die component is due to incorrect heat-treatment which did not remove the cold-worked structure in built in the material during production, thus resulting in inferior toughness and/or fatigue resistance. It was equally identified that occasional misalignment of the mould upper die teeth and lower die plate due to over exertion of the machine contributes to failure of the die material. [Copyright &y& Elsevier]

Abstract: Preservation and conservation of historical structures are the major points for the continuity of history. Therefore, in order to develop suitable restoration projects without neglecting any of the unique cultural values, it is very important to determine the present conditions of these structures. In this paper, it is aimed to present architectural and engineering properties of Turkish historical arch bridges. For this purpose, deteriorations in construction materials, damage and failure patterns occurred in the masonry arch bridges are classified and discussed using some illustrated photos. Some restoration practices for the bridges have been carried out by Turkish General Directorate of Highways are briefly discussed. [Copyright &y& Elsevier]

Abstract: Fatigue failure is a highly complex phenomenon and any attempt to provide a non-analytical or non-empirical analysis requires the effective classification and management of the data involved. The objective of this research is to create a non-analytical technique that assists detailing of potential fatigue initiating features at design conception. This paper reveals the research methodology behind the development of a new technique, concept design for fatigue resistance (CDFR). Firstly, in a survey of UK industry, current industrial practices in designing for fatigue resistance are investigated to justify the development of a new technique. Secondly, through analysis and cataloguing of 120 fatigue failure cases trends in fatigue mechanisms, their causes and specific factors that contributed to a variety of different feature’s fatigue failure mode(s) are developed. CDFR aims to synthesise the failure process for the designer considering the most frequently occurring factors related to the feature type and failure mode as identified from the failure case database. This paper examines the development of the CDFR technique leading to the proposed utilisation and integration of three powerful and proven approaches: expert system (ES), knowledge based system (KBS) and case-based reasoning (CBR) in order to aid the process of the identification and elimination of future fatigue problems at the earliest possible stages in the development of a product. [Copyright &y& Elsevier]

Abstract: A number of failures have recently occurred in glulam structures in the Scandinavian countries. This paper analyses and discusses two of these failures: Two recently built glulam roof structures with spans of about 75 and 55m that failed under low loading conditions. Gross error in the design was found to be the main cause in one case, but other potential failure causes were identified and analysed. The other structure failed mainly do to poor manufactured connections. By sheer luck, nobody was killed nor injured. Problems in the building process are discussed. In particular changes in the building organization, stronger clients and more time to planning and design are believed to improve poor quality. [Copyright &y& Elsevier]

• An experimental program is developed to assess the RTP behavior under lateral load impact. • Dents are fabricated using a quasi-static indentation procedure to burst the RTP specimens. • Relationships between the lateral load, indentation depth and the burst pressure is extracted. Reinforced Thermoplastic Pipe (RTP) is a flexible composite pipe that currently receives fair acceptance in the oil and gas industry, with high potentials to be used as a replacement to the carbon steel (CS) pipes especially in high corrosive environment. As RTP is relatively new products, their designs and qualifications are governed by the industry practice at present in the absence of comprehensive technical design standards. Most literatures to date are mainly dedicated to the intact RTPs, while the response of the pipe towards various defects have not been fully understood. Quite often, the assessments are made by referring to the design standards of the CS pipes, which are not entirely suitable due to the flexible characteristics of the composite pipe itself. Thus, this paper aims at assessing the performance of a 4″ RTP when exposed to lateral loads from external interferences such as the anchor dropped. Herein, the damaged to the RTP pipe was made in the form of a dent indented by a cylindrical conical nose under the quasi-static indentation procedures carried out experimentally. The damaged or dented pipe was later tested for its burst capacity using a burst testing facility specially fabricated for composite pipes. During the experiments, two types of failure modes were observed, namely single unit and ply-by-ply failures. Outcomes obtained from the experiments were used to describe the relationships between three important parameters, namely lateral load, indentation depth and burst pressure using polynomial regression equations. These simplified equations may be adopted directly in pipeline assessments and operations of RTP pipes exposed to dents. Moreover, outcomes from this paper will be beneficial in qualifying further RTP as a new free-corrosion risk transportation system for the oil and gas industry. [ABSTRACT FROM AUTHOR]