Background: Human errors are widely acknowledged as the primary cause of structural failures in the construction industry. Research has found that such errors arise from the situation created by human factors and organizational factors embedded in the task context. However, these contextual factors have not been adequately addressed in the construction industry. Therefore, this study aims to identify the critical Human and Organizational Factors (HOFs) that influence structural safety in frequently performed tasks in structural design and construction. Methods: Through a comprehensive literature review, a framework consisting of potential critical factors called the HOPE framework, is presented. To identify the most critical HOFs that contribute to human error occurrences, a questionnaire survey to experts in the Dutch construction industry was conducted. Finally, the resulting framework was compared with three actual structural failures for validation. Results: This study shows that the HOFs should be extended with project-related factors (P) and working environment-related factors (E) due to the fact that these task contextual conditions play a significant role in shaping professionals' on-the-job performance. Furthermore, a survey identified 14 HOFs as critical in contributing to an error-prone situation in the structural design and construction tasks. Conclusion: The presented HOPE framework and the identified critical HOFs for structural safety can assist engineers with better hazard identification and quality assurance in practice.

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Drift limits are useful thresholds; during design or retrofitting analyses, engineers can compare the expected behaviour of a structure to drift limits that predict when the structure will reach a certain condition. This helps ensure that structures satisfy specified performance goals when exposed to certain hazards. Masonry walls are susceptible to damage from lateral in-plane actions such as wind or earthquake loading; ensuring that in-plane drift remains sufficiently small will help limit this damage. Drift limits based on crack-based damage are scarce, however, with DS1 limits being extrapolated from higher damage grades based on structural strength capacity or ductility. In this work, crack-based damage is evaluated on a multitude of full-scale experimental walls surveyed with digital image correlation. This method observes the initiation and propagation of cracking. Cyclically incremental in-plane tests provide a range of drift-damage relationships. These are explored with machine learning to determine influential predictors and ultimately establish drift limits for light damage. Two types of brick masonry are explored: fired-clay and calcium-silicate. For the latter, light damage begins at an in-plane drift of 0.5 mm/m and can extend to 4.8 mm/m (or 0.48%) for the former before the masonry surpasses light damage and reaches structural damage grades. In comparison to drift limits set by other authors and (international) guidelines to characterise light damage, significant damage, or the ultimate capacity of masonry walls, the resulting drift limits for light damage from this work are set directly on the basis of experiments and are in good agreement with other authors. Most importantly, all the consulted values for ultimate capacity are much larger than the upper threshold for light damage determined herein, with limits for significant damage in the same order of magnitude. This result verifies the accuracy of the experimental crack-based characterisation used to establish the drift thresholds.@en

This study focuses on measuring the influence of critical Human and Organizational Factors (HOFs) on human error occurrence in structural design and construction tasks within the context of the Dutch construction industry. The primary research question addressed in this paper concerns the extent of HOFs’ contribution to human error occurrence. To answer this question, the Classical Model for Structured Expert Judgement (SEJ) is employed, enabling experts to provide their judgments on task Human Error Probability (HEP) influenced by different HOFs, which are subsequently aggregated mathematically. SEJ is chosen as a suitable approach due to the limited availability of applicable data in the construction sector. As a result, the impacts of HOFs are quantified as multipliers, representing the ratio between the observed or evaluated task HEP and its baseline value. These multipliers are then compared with corresponding multipliers from existing Human Reliability Analysis methods and studies. The findings reveal that fitness-for-duty, organizational characteristics and fragmentation exhibit the most pronounced negative effects, whereas complexity, attitude and fitness-for-duty demonstrate the most significant positive impacts on task performance. These results offer valuable insights that can be applied to enhance structural safety assurance practices.

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Historical masonry façades are sensitive to various damaging processes. A recent study, looking at the initiation and progression of cracks in masonry, in the range of 0.1 to 5 mm in width and thus corresponding to light damage [1], has allowed for the calibration of finite-element models that include a material model capable of accurately replicating this damage and which is populated with material properties corresponding to existing structures [6]. The models, which also include a soil-structure interaction boundary designed to account for the effect of the soil during earthquake vibrations [7], have been used to determine the fragility of masonry buildings via the proxy of 2D walls [2]. In the study presented herein, the finite element models are employed to replicate the geometry of (historical) masonry facades to determine their sensitivity to light damage as a consequence of the two damaging processes observed to be most common for this type of façade, namely (differential) settlements and (earthquake) vibrations [3]. The masonry façades were first pre-damaged via settlement distortions which generate just-visible cracks in the order of 0.1 mm to 1 mm in width. Then, an acceleration time history corresponding to two different Dutch earthquake events and two recordings of traffic-induced building vibrations [9] were separately applied at the base of the models. In this manner, the effect of existing damage could be assessed in regards to the aggravation generated by vibrations. The settlement part of the study revealed that long façades were more vulnerable to applied soil distortions, for instance. Then, subsequent vibrations further increased damage for intensities measured with a peak ground velocity (PGV) larger than 2 mm/s while the control set of virgin or uncracked façades remained undamaged at this PGV. At 32 mm/s, many pre-damaged façades also exceeded the light damage range. At equal PGV, the traffic vibrations, with a larger number of effective cycles, resulted in increased damage aggravation in comparison to the earthquake recordings.

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A broad review of the existing literature concerning Human and Organizational Factors (HOFs) and human errors influencing structural safety is presented in this study. Publications on this research topic were collected from the Scopus database. Two research focal points of this topic, namely modelling and evaluating the human error effects on structural reliability, and identifying causal factors for structural defects and failures, have been recognized and discussed with an in-depth literature review. The review of studies with a model focus summarizes the models and methods that have been developed to evaluate structural reliability considering human error effects. Besides, the review of publications on the factor subject outlines the most acknowledged HOFs that influence structural safety. Moreover, an additional spotlight was given to the studies from the offshore industry for the advanced development in HOFs and contributing the first complete Human Reliability Analysis (HRA) method for structural reliability analysis. In conclusion, this study provides a holistic overview of the knowledge developed in existing research on the topic of HOFs and human error influencing structural safety. Furthermore, current developments and challenges are reflected, and future research directions are explored for academics entering and working in this field. Additionally, the insights into HOFs generated from this review can assist engineers with better hazard identification and quality assurance in practice.

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Considering current trends in the Netherlands with regards to sustainability, there is a strong desire at Delft University of Technology to incorporate sustainable structural design strategies in the civil and structural engineering curriculum. Based on literature study and own experiences in practice, a coherent approach was developed, that can help students and practitioners to increase sustainability in their projects. The approach consists of a roadmap with 4 key strategies: increase lifespan of existing structures by reusing them, increase lifespan of existing structural elements by reusing them, design future proof and with a long-life span, and optimise the design for environmental impact. The strategies are explained and illustrated with examples.@en

MKI, MPG, BENG, CO2-neutraal, LCA, EPD, cascadering, circulair bouwen, donorskelet. De duurzaamheidsdiscussie is de laatste jaren opgelaaid en heeft geleid tot nieuwe termen, afkortingen en in gespecialiseerde duurzaamheidsconsultants met eigen jargon. Door de grote hoeveelheid en soms tegenstrijdige informatie, zie je door de bomen het bos niet meer. Wat is duurzaam construeren eigenlijk? Vraag het drie constructeurs en je krijgt vier verschillende antwoorden. Om de studenten van TU Delft hier meer houvast in te geven, is op basis van inzichten uit de literatuur en praktijkervaring een stappenplan opgezet. @en

This chapter focuses on human and organisational factors that are usually behind the technical cause of failure. This is illustrated by a case of the collapse of five balconies in 2003 in Maastricht (The Netherlands) resulting in two fatalities.@en

This chapter focuses on human and organizational factors that are usually behind the technical cause of failure. In this chapter the focus is on the collapse of the extension of the roof of the Football Club Twente stadium in Enschede (The Netherlands) during construction, resulting in two fatalities.@en

Constructieve veiligheid verbeteren; een thema dat mij al bezighoudt sinds ik in 2001 startte als constructeur. In de daaropvolgende jaren werd de bouw opgeschrikt door de ingestorte balkons in Maastricht (2003) en de schade bij het parkeerdek Bos & Lommer (2006). Ik werd me bewust van de grote verantwoordelijkheid die een constructeur heeft en raakte geïntrigeerd door de vraag hoe in een ontwikkeld land als Nederland er zaken faliekant mis konden gaan in de bouw en tot instortingen konden leiden.@en

Column 13 september 2022: Geotechnisch adviseur en docent Bert Everts en hoogleraar geotechniek Arnold Verruijt; afgelopen zomer ontving ik bericht van het overlijden van deze gewaardeerde leermeesters. Deze berichten deden mij stilstaan bij mijn eigen leermeesters, die mij leerden hoe je mooier, veiliger en duurzamer kunt ontwerpen en op een leukere manier kunt samenwerken.@en

Biopartner 5 is de eerste grootschalige toepassing van het Donorskelet-principe. Een 3D BIM-model van het bestaande gebouw is opgesteld om de gecodeerde elementen te kunnen relateren aan hun nieuw positie. Biopartner 5 is ook het hoogst haalbare langs de meetlat van duurzaam construeren, zonder daarbij de kosten uit het oog te verliezen. De verbindingen tussen de kanaalplaten en de stalen liggers zijn demontabel, maar hebben ook een rol in de schijfwerking. Er is wel van sprake van een traditionele fundering: dit blijft vooralsnog de grote opgave voor toekomstige projecten. @en

Column 18 mei 2021: “Ga je nu alleen nog vegetarische gebouwen maken?”. Onlangs voerde ik een levendige discussie met een architect, die alleen nog aan duurzame, ‘Paris Proof’-projecten wilde werken. Dit gesprek zette me aan het denken. Hoe sta ik hier zelf in?@en

During the last decade a lot of attention has been paid to sustainability of structures. Reuse of existing buildings, limiting environmental impact and reuse of elements were applied in practice. In general, reuse of elements, with for instance the use of a donor skeleton, was applied on a very limited scale, as this reuse often comes at a price. In 2018 there was an opportunity to apply a donor skeleton on a larger scale in an office building of 6200 m2. This paper will describe the process of design and construction of this special project, and will derive lessons learned in order to increase application of upscaling of building elements in future projects.@en

Column 25 november 20211:Tijdens mijn studie in Delft stelde een hoogleraar: “Een goede constructeur is een luie constructeur!” Een uitspraak die bij mij bleef hangen. Wat hij bedoelde was dat een constructeur eerst goed moet nadenken over een probleem voordat hij als een dolle sommetjes gaat maken.@en

In this paper, we provide an overview of how Safe-by-Design is conceived and applied in practice in a large number of engineering disciplines. We discuss the differences, commonalities, and possibilities for mutual learning found in those practices and identify several ways of putting those disciplinary outlooks in perspective. The considered engineering disciplines in the order of historically grown technologies are construction engineering, chemical engineering, aerospace engineering, urban engineering, software engineering, bio-engineering, nano-engineering, and finally cyber space engineering. Each discipline is briefly introduced, the technology at issue is described, the relevant or dominant hazards are examined, the social challenge(s) are observed, and the relevant developments in the field are described. Within each discipline the risk management strategies, the design principles promoting safety or safety awareness, and associated methods or tools are discussed. Possible dilemmas that the designers in the discipline face are highlighted. Each discipline is concluded by discussing the opportunities and bottlenecks in addressing safety. Commonalities and differences between the engineering disciplines are investigated, specifically on the design strategies for which empirical data have been collected. We argue that Safe-by-Design is best considered as a specific elaboration of Responsible Research and Innovation, with an explicit focus on safety in relation to other important values in engineering such as well-being, sustainability, equity, and affordability. Safe-by-Design provides for an intellectual venue where social science and the humanities (SSH) collaborate on technological developments and innovation by helping to proactively incorporate safety considerations into engineering practices, while navigating between the extremes of technological optimism and disproportionate precaution. As such, Safe-by-Design is also a practical tool for policymakers and risk assessors that helps shape governance arrangements for accommodating and incentivizing safety, while fully acknowledging uncertainty.

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In 2011 the city of Enschede was shocked by the collapse of the roof of an extension for the FC Twente stadium. The structure collapsed during construction and two fatalities and nine injuries were recorded. The cantilevering steel roof structure was covered with corrugated steel sheets and stabilized by bracings. Investigation showed that the structure was already loaded with the finishing structure before it was completed and stabilized. Contributing influencing human and organizational factors to the incident were the tight schedule resulting in a flawed construction sequence. Furthermore, there was too little attention to the way of execution during design, unjustified trust between parties resulting in inadequate coordination, checking and allocation of responsibilities.

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Column 18 mei 2021: “Heeft u het hout al binnen een jaar nodig?”, vroeg de leverancier van kruisgelaagd hout (CLT) die ik afgelopen week aan de telefoon had. Hout is hot. Sterker nog: het is niet oké als je niet van hout houdt. Want hout is duurzaam, en duurzaam is goed voor de planeet en toekomstige generaties. Nederland kent alleen nog maar houtliefhebbers. Behoudens misschien een paar lezers van Cement, die hout niet grijs genoeg vinden… @en