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The purpose of this paper is to determine the failure progression resistance of the steel moment-resisting frames subjected to various beam-removal scenarios after application of the design earthquake pertinent to the structure by investigating a generic eight-story building.

The structure is first pushed to arrive at a target roof displacement corresponding to life safety level of performance. To simulate the post-earthquake beam-removal scenario, one of the beam elements is suddenly removed from the structure at a number of different positions. The structural response is then evaluated by using nonlinear static and dynamic analyses.

The results show that while no failure is observed in all of the scenarios, the vulnerability of the upper stories is much greater than that of the lower stories. In the next step, the structural resistance to such scenarios is determined. The results confirm that for the case study structure, at most, the resistance to failure progression in upper stories is 58 percent more than that of lower stories.

Failure and fracture of beam-to-column connections resulting in removal of beam elements may lead to a chain of subsequent failures in other structural members and eventually lead to progressive collapse in some cases. Deficiency in design or construction process of structures when combined by application of seismic loads may lead to such an event.

The purpose of this paper is to briefly summarize and review the theories and methods of complex structures’ dynamic reliability. Complex structures are usually assembled from multiple components and subjected to time-varying loads of aerodynamic, structural, thermal and other physical fields; its reliability analysis is of great significance to ensure the safe operation of large-scale equipment such as aviation and machinery.

In this paper for the single-objective dynamic reliability analysis of complex structures, the calculation can be categorized into Monte Carlo (MC), outcrossing rate, envelope functions and extreme value methods. The series-parallel and expansion methods, multi-extremum surrogate models and decomposed-coordinated surrogate models are summarized for the multiobjective dynamic reliability analysis of complex structures.

The numerical complex compound function and turbine blisk are used as examples to illustrate the performance of single-objective and multiobjective dynamic reliability analysis methods. Then the future development direction of dynamic reliability analysis of complex structures is prospected.

The paper provides a useful reference for further theoretical research and engineering application.

Lack of strict compliance to the principles of total quality management (TQM) by construction organizations has brought about poor quality of the finished building projects. This has been blamed for the incessant structural failure reported in Nigeria. This study appraised TQM implementation in the Nigerian construction industry, with a view to mitigating structural failure rate of construction projects. To achieve this aim, the study aims to assess the practice level of TQM and the factors hindering TQM implementation on construction projects.

The study utilized a well-structured questionnaire and convenient sampling method in the gathering and sampling of data among construction professionals in Imo state, Nigeria. Data analyses were done using, frequency, percentage, mean analytics and Pareto analysis.

The study revealed that major practice of TQM principles with respect to structural failure rate are purchasing: ensuring the procurement of materials of the specified quality standard, ensuring the use of a quality improvement construction process of the organization, site management responsibility: this entails ensuring quality supervision by the project management leadership and monitoring and control of quality during the construction to guarantee firm observance quality standards. Also, the major factors hindering TQM implementation on construction projects are: inadequacy of the necessary machineries, equipment, tools and facilities for the effective execution of work on construction site; breakdown in communication and information exchange between the management and supervisory teams on site; poor attitudes and strategies toward maintenance of equipment, tools and machines; and absence of prompt salary and incentive payment. It was recommended that construction firms must require the suppliers of construction materials to strictly comply with quality specification evidence in quality certification of delivered materials to mitigate structural failure.

This study appraised TQM implementation in the construction industry of Nigeria, with emphasis on Imo state. The study underscores the practice level of TQM and the key factors hindering TQM implementation on construction projects. Following the localized geographical limitation of the study area, a similar research in other part/states of Nigeria or even in other developing countries of African is necessary.

The practices level of TQM and the factors hindering TQM implementation were identified. This will be useful in guiding construction firms, other industry's key stakeholders and regulatory agencies in bringing about a sustainable quality management system for improve profit and value maximization and avoiding incessant structural failure.

This is one of the few studies that have assessed the practice level of TQM and the factors hindering TQM implementation on construction projects in Nigeria. This study took place in Imo state with records of periodic structural failure and building collapse.

This paper aims to provide a comprehensive review of uncertainty quantification methods supported by evidence-based comparison studies. Uncertainties are widely encountered in engineering practice, arising from such diverse sources as heterogeneity of materials, variability in measurement, lack of data and ambiguity in knowledge. Academia and industries have long been researching for uncertainty quantification (UQ) methods to quantitatively account for the effects of various input uncertainties on the system response. Despite the rich literature of relevant research, UQ is not an easy subject for novice researchers/practitioners, where many different methods and techniques coexist with inconsistent input/output requirements and analysis schemes.

This confusing status significantly hampers the research progress and practical application of UQ methods in engineering. In the context of engineering analysis, the research efforts of UQ are most focused in two largely separate research fields: structural reliability analysis (SRA) and stochastic finite element method (SFEM). This paper provides a state-of-the-art review of SRA and SFEM, covering both technology and application aspects. Moreover, unlike standard survey papers that focus primarily on description and explanation, a thorough and rigorous comparative study is performed to test all UQ methods reviewed in the paper on a common set of reprehensive examples.

Over 20 uncertainty quantification methods in the fields of structural reliability analysis and stochastic finite element methods are reviewed and rigorously tested on carefully designed numerical examples. They include FORM/SORM, importance sampling, subset simulation, response surface method, surrogate methods, polynomial chaos expansion, perturbation method, stochastic collocation method, etc. The review and comparison tests comment and conclude not only on accuracy and efficiency of each method but also their applicability in different types of uncertainty propagation problems.

The research fields of structural reliability analysis and stochastic finite element methods have largely been developed separately, although both tackle uncertainty quantification in engineering problems. For the first time, all major uncertainty quantification methods in both fields are reviewed and rigorously tested on a common set of examples. Critical opinions and concluding remarks are drawn from the rigorous comparative study, providing objective evidence-based information for further research and practical applications.

The study investigates the performance of a three-story unprotected steel moment-resisting frame (SMRF) designed for high seismic demand in the fire-only (FO) and post-earthquake uniform and traveling fires (PEF). The primary objective is to investigate the effects of seismic residual deformation on the structure's performance in horizontally traveling fires. The traveling fire methodology, unlike conventional fire models, considers a spatially varying temperature environment.

Multi-step finite element simulations were carried out on undamaged and damaged frames to provide insight into the effects of the earthquake-initiated fires on the local and global behavior of SMRF. The earthquake simulations were conducted using nonlinear time history analysis, whereas the structure in the fire was investigated by sequential thermal-structural analysis procedure in ABAQUS. The frame was subjected to a suite of seven ground motions. In total, four horizontal traveling fire sizes were considered along with the Eurocode (EC) parametric fire for a comparison. The deformation history, axial force and moment variation in the critical beams and columns of affected compartments in the fire heating and cooling regimes were examined. The global structural performance in terms of inter-story drifts in FO and PEF scenarios was investigated.

It was observed that the larger traveling fires (25 and 48%) are more detrimental to the case study frame than the uniform EC parametric fire. Besides, no appreciable difference was observed in time and modes of failure of the structure in FO and PEF scenarios within the study's parameters.

The present study considers improved traveling fire methodology as an alternate design fire for the first time for the PEF performance of SMRF. The analysis results add to the much needed database on structures' performance in a wide range of fire scenarios.

Despite recognizing the significance of risk-based frameworks in fire safety engineering, the usual approach in structural fire design is largely member/component level, wherein effect of uncertainties influencing the fire resistance of structures are not explicitly considered. In this context, a probabilistic framework is presented to investigate the vulnerability of a reinforced concrete (RC) members and structure under fire loading scenario.

The RC structures exposed to fire are modeled in a finite element (FE) platform incorporating material and geometric nonlinearity, in which the transient thermo-mechanical analysis is carried out by suitably incorporating the temperature variation of thermal and mechanical properties of both concrete and steel rebar. The stochasticity in the system is considered in structural resistance, thermal and fire model parameters, and the subsequent fragility curves are developed considering threshold limit state of deflection.

The fire resistance of RC structure is reported to be significantly lower in comparison to the RC members, thereby illustrating the current prescriptive design approaches based on studies of structural member behavior to be crucial from a safety and reliability point of view.

The framework developed for the vulnerability assessment of RC structures under fire hazard through FE analysis can be effectively used to estimate the structural fire resistance for other similar structure to enhance safety and reliability of structures under such extreme threats.

The paper proposes a novel methodology for vulnerability assessment of three-dimensional RC structures under fire hazard through FE analysis and provides comparison of the structural fragility with fragility developed for structural members. Moreover, the research emphasizes to assume 3D behavior of the structure rather than the approximate 2D behavior.

This study aims to discover the impact of failure factors on stakeholder coordination performance (SCP) in the finishing phase of high-rise building projects.

Firstly, this study identifies potential failure factors affecting coordination performance as well as criteria for measuring SCP in the finishing phase of high-rise building projects. Afterwards, a survey questionnaire is designed to collect data from high-rise building projects in Vietnam. Using the factor analysis method, the study discovers the failure constructs. A structural equation model is then built to uncover the relationships between failure constructs and SCP.

The study identified four failure constructs which could significantly affect SCP, namely traditional adversarial relationship (TAR), incompetent parties (IP), poor project planning and organization (PPO) and delays of parties toward construction works (DP). The developed model indicated that TAR, PPO and IP significantly affected stakeholders' coordination performance in the finishing phase of high-rise building projects.

The results of the study fill the gap in knowledge by discovering the causal relationships between failure constructs and SCP in high-rise building projects. The results might provide an initial guideline for stakeholders during the finishing phase of high-rise building projects to enhance their coordination performance.

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

The purpose of this paper is to carry out the application of risk reliability-based underwater inspection (RReBUI).

The consequence of failure factor is calculated qualitatively in accordance with the risk-based underwater inspection (RBUI) method but the criteria are modified as an adjustment to the addition and combination of production and reliability information of the analyzed platforms. The probability of failure (PoF) is determined quantitatively by calculating the structure reliability index based on collapse failure mechanism in which the uncertainty of wave load is considered. The PoF criteria from the RBUI are re-modified to adjust the criterion with the highest and lowest reliability indexes obtained in RReBUI study. Selection of exposure category of the platform is still the same as the RBUI method.

The models of three offshore jacket platforms located in each of Java Sea and Natuna Sea were used for the RReBUI application. These six models were previously used in the traditional RBUI application. The results of RReBUI analysis indicated that including the environmental characteristics in the risk assessment resulted in more reliable inspection interval plans.

The drawback of RBUI is that it cannot be used for platforms spread over a distance or different areas, as the failure parameters of these platforms cannot be compared. Furthermore, the RBUI method does not consider the environmental characteristics in its risk assessment. Unlike RBUI, the purpose of RReBUI method is to assess the reliability of a platform based on both structural and environment characteristics. Therefore, the RReBUI method determines the risk of every platform quantitatively without having to compare the failure parameters based on expert justification. The application of RReBUI for jacket platforms has never been developed in Indonesia.

What constitutes a failure? A failure is not necessarily a total collapse causing damage or loss of life — these are extreme cases. And to analyse failures, it is first necessary to determine the function which the cladding of a building serves.