Structural Safety最新文献

{"title":"An enhanced learning function for bootstrap polynomial chaos expansion-based enhanced active learning algorithm for reliability analysis of structure","authors":"Avinandan Modak,&nbsp;Subrata Chakraborty","doi":"10.1016/j.strusafe.2024.102467","DOIUrl":"10.1016/j.strusafe.2024.102467","url":null,"abstract":"<div><p>Sparse polynomial chaos expansion (PCE) combined with the bootstrap resampling method is a viable alternative to obtain an active learning algorithm for reliability analysis. The existing learning functions in PCE-based active learning algorithms do not consider the joint probability density function (PDF) information. The present study explores a sparse PCE-based active learning algorithm based on a newly proposed learning function that maintains a balance between the misclassification probability and the joint PDF information of sample points. In doing so, the coefficients of the sparse PCE are estimated using a Bayesian compressive sensing regressor, as it is noted to be one of the best-performing regression solvers for PCE, irrespective of sampling schemes. The proposed learning function considers the weight of the joint PDF with the local accuracy measure of bootstrap PCE (bPCE) to add new samples iteratively in the existing training set. The convergence is achieved when the ten consecutive failure estimates are within a negligible discrepancy and also checks the confidence bounds of the bPCE estimates. The effectiveness of the proposed approach is demonstrated using two structural engineering examples and one well-known analytical test function and is found to be quite efficient and accurate in estimating reliability.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102467"},"PeriodicalIF":5.8,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140270214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probabilistic design procedure for steel moment resisting frames equipped with FREEDAM connections","authors":"Maria Maglio ,&nbsp;Rosario Montuori ,&nbsp;Elide Nastri ,&nbsp;Vincenzo Piluso ,&nbsp;Alessandro Pisapia","doi":"10.1016/j.strusafe.2024.102465","DOIUrl":"https://doi.org/10.1016/j.strusafe.2024.102465","url":null,"abstract":"<div><p>In this work, the Theory of Plastic Mechanism Control (TPMC) is combined with a probabilistic method to account for the influence of random material variability. Reference is made to steel Moment Resisting Frames (MRFs) equipped with FREEDAM connections. FREEDAM connections are beam-to-column connections equipped with friction dampers to dissipate the seismic input energy. TPMC is used to guarantee that in case of destructive seismic events the structural members such as beams and columns remain undamaged. To this scope, the structure is designed to assure a collapse mechanism characterized by the activation of all the friction dampers of the beam ends and the formation of plastic hinges at the base of the first storey columns only. From the probabilistic point of view, the random uncertainties are given by the static friction coefficient of the contact surfaces and the preloading of the bolts of the friction dampers as well as the yielding resistance of the steel members. The failure domain is related to all the possible failure events, where the term “failure” concerns the development of an undesired mechanism different from the global one. Generally, the design conditions to prevent undesired collapse mechanisms are stochastic events within the framework of the kinematic theorem of plastic collapse. The limit state function corresponding to each event can be represented by a hyperplane in the space of random variables. Consequently, the failure domain is a surface resulting from the intersection of the hyperplanes corresponding to the limit states of each single failure event. Since dissipative zones (member ends or friction dampers) in the frame members are common to many different mechanisms, the single limit state functions are correlated. Therefore, the probability of failure can be evaluated by means of the Bimodal or Ditlevsen bounds by assuming that the failure events are located in series. The output of the work is a simple relationship which provides the overstrength factor of FREEDAM connections to be considered in the column design phase to account for random material variability thus assuring a given level of reliability in the application of TPMC.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102465"},"PeriodicalIF":5.8,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0167473024000365/pdfft?md5=4aaeea824030879c70b75a69c0c556f2&pid=1-s2.0-S0167473024000365-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140138887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the derivation of the delta formulation for decision value","authors":"Sebastian Thöns","doi":"10.1016/j.strusafe.2024.102466","DOIUrl":"10.1016/j.strusafe.2024.102466","url":null,"abstract":"<div><p>This paper contains decision analytical approaches, conditions and models for the quantification of decision values for built environment systems. Specifically, (1) delta formulations of objective functions for decision value quantification are introduced, (2) conditions for decision value are identified and (3) action value analysis formulations are further developed. The delta objective functions are formulated with differences in utility, cost, and probabilities for consistent decision identification by expected utility and value. The delta formulations facilitate the direct calculation of action and information values and the explication of conditions for a positive decision value. Action value objective functions are derived in delta formulation for the action types of utility and system state actions and with action implementation states and action uncertainty models. The delta formulations are exemplified for predicted information and predicted actions values. The paper closes with a synthesis and discussion of decision values and with findings encompassing a computational effort reduction and the identification of predicted information value mechanisms.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102466"},"PeriodicalIF":5.8,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0167473024000377/pdfft?md5=c719fb54a4b017ce8ab377079b2dddab&pid=1-s2.0-S0167473024000377-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140152355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GELF: A global error-based learning function for globally optimal adaptive reliability analysis","authors":"Chi Zhang ,&nbsp;Chaolin Song ,&nbsp;Abdollah Shafieezadeh","doi":"10.1016/j.strusafe.2024.102464","DOIUrl":"10.1016/j.strusafe.2024.102464","url":null,"abstract":"<div><p>Kriging has gained significant attention for reliability analysis primarily because of the analytical form of its uncertainty information, which facilitates adaptive training and establishing stopping criteria for the training process. Learning functions play a significant role in both selection of training points and stoppage of the training. For these functions, most existing learning functions evaluate candidate training points individually. However, lack of consideration for the global effects can lead to suboptimal training. In addition, the subjectivity of these stopping criteria may result in over or undertraining of surrogate models. To overcome these gaps, we propose Global Error-based Learning Function (GELF) for optimal refinement of Kriging surrogate models for the specific purpose of reliability analysis. Instead of prioritizing training points based on their uncertainty and proximity to the limit state like the existing learning functions, GELF for the first time directly and analytically associates the maximum error in the failure probability estimate to the global effect of choosing a candidate training point. This development subsequently facilitates an adaptive training scheme that minimizes the error in adaptive reliability estimation to the highest degree. For this purpose, GELF uses hypothetical future uncertainty information by treating the current construction of the surrogate model as a generative model. The proposed method is tested on three classic benchmark problems and one practical engineering problem. Results indicate that the proposed method has significantly better computational efficiency than the state-of-the-art methods while achieving high accuracy in all the numerical examples.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102464"},"PeriodicalIF":5.8,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0167473024000353/pdfft?md5=318812f372fbadc61cb65870999eed63&pid=1-s2.0-S0167473024000353-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140152354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Johan Spross","doi":"10.1016/j.strusafe.2024.102455","DOIUrl":"https://doi.org/10.1016/j.strusafe.2024.102455","url":null,"abstract":"","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102455"},"PeriodicalIF":5.8,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140062106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction and correlations estimation of seismic capacities of pier columns: Extended Gaussian process regression models","authors":"Ruchun Mo ,&nbsp;Libo Chen ,&nbsp;Yu Chen ,&nbsp;Chuanxiang Xiong ,&nbsp;Canlin Zhang ,&nbsp;Zhaowu Chen ,&nbsp;En Lin","doi":"10.1016/j.strusafe.2024.102457","DOIUrl":"https://doi.org/10.1016/j.strusafe.2024.102457","url":null,"abstract":"<div><p>Assessing the seismic capacity of pier columns is a crucial element in the performance-based seismic design of bridges. Such assessment necessitates a probabilistic approach to accurately determine the marginal probability distributions of seismic capacities and to characterize the dependencies among these variables. In response to this need, this paper employs Multi-Output Gaussian Process Regression (MO-GPR), a probabilistic machine learning method, to jointly model the multiple seismic capacities of pier columns. We initially introduce a probabilistic seismic capacity model that utilizes MO-GPR for pier columns and validate its predictive accuracy in comparison to Bayesian linear regression and existing empirical methods. Subsequently, the methodology is augmented by the integration of hierarchical modeling within the MO-GPR framework, resulting in a Multi-Output Hierarchical Gaussian Process Regression (MO-HGPR) model that effectively estimates intraclass correlation coefficients for specific types of datasets. It is postulated that these correlation coefficients also reflect correlations associated with multiple components of the real structure. This study employs MO-HGPR and MO-GPR separately to investigate the potential correlations of seismic capacities among pier columns and distinct limit states. The results demonstrate that the MO-GPR model exhibits superior prediction accuracy and more effectively portrays uncertainty compared to existing empirical models. Moreover, the correlations of seismic capacities among piers and limit states are both robust and significantly impact the seismic fragility of bridges. This finding highlights the essential nature of considering capacities correlations in seismic fragility or risk assessment processes.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"109 ","pages":"Article 102457"},"PeriodicalIF":5.8,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140030389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On reliability assessment of existing structures","authors":"Dimitris Diamantidis ,&nbsp;Peter Tanner ,&nbsp;Milan Holicky ,&nbsp;Henrik O. Madsen ,&nbsp;Miroslav Sykora","doi":"10.1016/j.strusafe.2024.102452","DOIUrl":"10.1016/j.strusafe.2024.102452","url":null,"abstract":"<div><div>This contribution discusses the reliability assessment of existing structures emphasizing on developments within or initiated by the JCSS. After a bibliographical review, the principles of reliability updating, i.e. Bayesian updating of random variables and updating of event probabilities are summarized. Developments in standards and established verification formats—partial factor or load and resistance factor, reliability-based, and risk-informed—are briefly presented and discussed. The impact of JCSS work in recent standards such as ISO 13822, the draft Eurocode prEN1990-2, and the <em>fib</em> Model Code 2020 as well as in national standards is highlighted. Criteria for defining target reliabilities for existing structures including human safety and optimization are critically reviewed. Obstacles for a wider implementation of reliability-based and risk-informed methods in practice are identified and conclusions for future developments are drawn. Finally, Annex A illustrates updating procedures for resistance variables and Annex B presents a case study.</div></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"113 ","pages":"Article 102452"},"PeriodicalIF":5.7,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140017443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probabilistic modelling of deterioration of reinforced concrete structures","authors":"Dimitri V. Val ,&nbsp;Carmen Andrade ,&nbsp;Miroslav Sykora ,&nbsp;Mark G. Stewart ,&nbsp;Emilio Bastidas-Arteaga ,&nbsp;Jan Mlcoch ,&nbsp;Quynh Chau Truong ,&nbsp;Charbel-Pierre El Soueidy","doi":"10.1016/j.strusafe.2024.102454","DOIUrl":"10.1016/j.strusafe.2024.102454","url":null,"abstract":"<div><div>Reinforced concrete (RC) structures deteriorate over time which affects their strength and serviceability. To develop measures for protecting new RC structures against deterioration and assess the condition of existing RC structures subjected to deterioration an understanding of the deterioration processes and the ability to predict their development, including structural consequences, are essential. This problem has attracted significant attention from researchers, including those working in the area of structural reliability (in particular within the JCSS) since there are major uncertainties associated with the deterioration processes and their structural effects. The paper presents an overview of the probabilistic modelling of various deterioration processes affecting RC structures such as corrosion of reinforcing steel, freezing-thawing, alkali-aggregate reaction, sulphate attack and fatigue, and their structural implications, including the historical perspective and current state-of-the-art. It also addresses the issues related to the inspection/monitoring of deteriorating RC structures and the analysis of collected data taking into account relevant uncertainties. Examples illustrating the application of the presented probabilistic models are provided. Finally, the current gaps in the knowledge related to the problem, which require further attention, are discussed.</div></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"113 ","pages":"Article 102454"},"PeriodicalIF":5.7,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140017468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Life safety in the Reliability-Based design and assessment of structures","authors":"Mahesh Pandey ,&nbsp;Celeste Viljoen ,&nbsp;Andrew Way ,&nbsp;Katharina Fischer ,&nbsp;Miroslav Sýkora ,&nbsp;Dimitris Diamantidis ,&nbsp;Raphaël D.J.M. Steenbergen ,&nbsp;Niels Lind ,&nbsp;Dan M. Frangopol ,&nbsp;David Y. Yang ,&nbsp;Johan V. Retief ,&nbsp;João André ,&nbsp;Jatin Nathwani ,&nbsp;Roman Lenner","doi":"10.1016/j.strusafe.2024.102453","DOIUrl":"10.1016/j.strusafe.2024.102453","url":null,"abstract":"<div><div>We review the developments in life safety and the incorporation thereof in the design and assessment of structures over the last 50 years. Various measures of life safety are presented that have been developed according to the marginal life saving cost principle based on individual, societal and economic considerations. Target probabilities of failure, or target reliabilities, are central to modern structural design and assessment. These are derived either through back-calibration to existing practice or through life cycle cost minimisation, both of which yield comparable safety levels, and are underpinned by lower bounds from life safety. Life cycle cost minimisation is reviewed here, which considers all direct and indirect costs of failure including loss of life and limb, as well as the costs and efficiency of increasing reliability. We discuss the incorporation of life safety into reliability-based design and assessment through the concept of the Life Quality Index, which uses key societal indicators, namely, the GDP and life expectancy, and health economics as a basis for specifying minimum reliabilities for both new and existing structures. The current state of advancement of reliability- and risk-informed design, and recommendations for future developments in life safety are considered.</div></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"113 ","pages":"Article 102453"},"PeriodicalIF":5.7,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140463647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eurocode-compliant system-level reliability analyses of trussed portal frames under climatic loads","authors":"Lauri Jaamala ,&nbsp;Henna Hietikko-Kaukola ,&nbsp;Kristo Mela ,&nbsp;Juha Tulonen ,&nbsp;Anssi Hyvärinen","doi":"10.1016/j.strusafe.2024.102451","DOIUrl":"10.1016/j.strusafe.2024.102451","url":null,"abstract":"<div><p>Eurocode 3 provides <strong>G</strong>eometrically and <strong>M</strong>aterially <strong>N</strong>onlinear <strong>A</strong>nalysis with <strong>I</strong>mperfections-method (GMNIA) in which the entire structure can be designed in system-level. In GMNIA, reliability of structural system is verified by using a system safety factor which is obtained in Eurocode 3 based on numerical or experimental capacity test results. Unfortunately, such test results are scarcely published in the literature thus complicating the determination of the factor for a design engineer. In the so-called Direct Design Method, however, system safety factors are provided in advance for the design engineer by system-level reliability studies. This study determines the Eurocode-compliant GMNIA system safety factor for Warren truss portal frames by using the approach of the Direct Design Method. Advanced numerical models are utilized to perform Monte Carlo-simulations for entire structural systems. These simulations provide statistical distributions of system resistances which are employed in the First-Order Reliability Method to derive the system safety factors. Studied structures are made of S700 cold-formed hollow sections. Various system geometries, system configurations and load combinations consisting of snow and wind loads are investigated and a suitable system safety factor is proposed for the ultimate limit state design of Warren truss portal frames. The proposed system safety factor is applied in a practical comparison in which Warren system is designed both by the conventional Eurocode 3 method and GMNIA. This comparison reveals that GMNIA has a remarkable potential to offer reduced material consumption in design compared to the conventional method.</p></div>","PeriodicalId":21978,"journal":{"name":"Structural Safety","volume":"108 ","pages":"Article 102451"},"PeriodicalIF":5.8,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0167473024000225/pdfft?md5=b59d0cbe447a44d4e72132efbdc11a98&pid=1-s2.0-S0167473024000225-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139923174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}