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Based on the advantages of conventional hot-dip galvanizing made from quasi-pure zinc melts in the event of fire, this article aims to perform a series of tests to verify whether a similar effect can be achieved with zinc-aluminum coatings.

The emissivity of galvanized surfaces, which were applied to steel specimens by the batch hot-dip galvanizing process, was experimentally determined under continuously increasing temperature load. In addition to a quasi-pure zinc melt serving as a reference, a zinc melt alloyed with 500 ppm aluminum and thin-film galvanized with a melt of zinc and 5% aluminum were used. For the latter, variants of post-treatment measures in terms of a passivation and sealing of the galvanizing were also investigated.

The results show that lower emissivity can be achieved at higher temperatures by adding aluminum to the zinc melt and thereby into the zinc coating. The design values required for the structural fire design were proposed, and an exemplary calculation of the temperature development in the case of fire was carried out based on the values. The result of this calculation indicates that the savings potential becomes apparent, when using zinc-aluminum coatings.

The presented novel tests describe the behavior of zinc-aluminum coatings under the influence of elevated temperatures and their positive effect on the emissivity of steel components galvanized by this method. The results provide valuable insights and information on the performance in the event of fire and the associated potential savings for steel construction.

Based on the known positive effects of conventional hot-dip galvanizing under fire exposure and indicative results on zinc–aluminum coatings from smallscale tests, a series of tests were conducted on zinc-5% aluminum galvanized test specimens under fire loads to verify the previous positive findings under largescale boundary conditions.

The emissivity of zinc-5% aluminum galvanized surfaces applied to steel specimens was determined experimentally under real fire loads and laboratory thermal loads in accordance with the normative specifications of the standard fire curve. Both large and smallscale specimens were used in this study. The steel grade and surface conditions of the specimens were varied for both test scenarios.

Largescale tests on specimens with typical steel construction dimensions under fire loads showed that the surface emissivity of zinc-5% aluminum galvanized steel was significantly lower than that of the conventionally galvanized steel. Only minor influences from the weathering of the specimens and steel chemistry were observed. These results agree well with those obtained from smallscale tests. The design values of zinc-5% aluminum melt (Zn5Al) required for the structural fire design were proposed based on the obtained results.

The novel tests presented in this study are the first ones to study the behavior of zinc-5% aluminum galvanized largescale steel construction components under the influence of real fire exposure and their positive effect on the emissivity of steel components galvanized by this method. The results provide valuable insights and information on the behavior in the case of fire and the associated savings potential for steel construction.

In this paper, the research program “Optimized use of intumescent coating systems on steel members” is presented. The aim of the project is to quantify the influence of space-enclosing elements on the thermal behavior of supporting steel members. Those elements partially result in a restrained expansion of the fire protection system. Experimental investigations on coated beams and columns directly connected to space-enclosing elements are presented. Additionally, numerical simulations are performed for temperature field calculations of steel elements with intumescent coating. As a new development, the numerical model takes into account the expansion process of the intumescent coating.

Past research showed that overly positive attitudes and intentions towards fast food contribute to obesity. In the face of rising childhood obesity, the purpose of this paper is to explore attitudinal and behavioral reasons behind adolescents' suboptimal food choices. It tests hypotheses about differences between teenagers and adults in customer attitudes and intentions regarding fast food restaurants.

The hypotheses are tested with German survey data and moderated regression analysis.

Teenagers do not underestimate the negative effects of fast food. However, their decision making fails to incorporate existing knowledge on competitive advantages and gives greater weight to customer satisfaction compared with adults. Behavioral differences between teenage and adult consumers result from differences in cognitive development rather than social pressure.

As this study uses subjective consumer data from Germany, future research could validate the conclusions with objective behavioral data from various countries.

Of importance to fast food restaurant managers, the primary determinants of customer attitudes and intentions are food quality, the public brand image, social recognition, and perceived competitive advantages. By contrast, service quality and perceived value are less influential. Satisfying teenage customers is more important than informing them about competitive advantages.

The results imply that fast food‐related childhood obesity may be caused by lack of rationality rather than peer pressure or lack of knowledge.

As an original contribution, the paper compares adolescents' and adults' decision making regarding fast food restaurants and captures the regularly overlooked influences of the public brand image, social recognition, and perceived competitive advantages.

This paper aims to investigate the need for active boundary conditions during fire testing of structural elements, review existing studies on hybrid fire testing (HFT), a technique that would ensure updating of boundary conditions during a fire test, and propose a compensation scheme to mitigate instabilities in the hybrid testing procedure.

The paper focuses on structural steel columns and starts with a detailed literature review of steel column fire tests in the past few decades with varying axial and rotational end restraints. The review is followed with new results from comparative numerical analyses of structural steel columns with various end constraints. HFT is then discussed as a potential solution to be adapted for fire testing of structural elements. Challenges in contemporary HFT procedures are discussed, and application of stiffness updating approaches is demonstrated.

The reviewed studies indicate that axial and rotational restraints at the boundaries considerably influence the fire response of steel columns. Equivalent static spring technique for simulating effect of surrounding frame on an isolated column behavior does not depict accurate buckling and post-buckling response. Additionally, numerical models that simulate fire performance of a column situated in a full-frame do follow the trends observed in actual test results up until failure occurs, but these simulations do not necessarily capture post-failure performance accurately. HFT can be used to capture proper boundary conditions during testing of isolated elements, as well as correct failure modes. However, existing studies showed cases with instabilities during HFT. This paper demonstrates that a different stiffness updates calculated from the force-displacement response history of test specimen at elevated temperature can be used to resolve stability issues.

The paper has two contributions: it suggests that the provision of active boundary conditions is needed in structural fire testing, as equivalent static spring does not necessarily capture the effect of surrounding frame on an isolated element during a fire test, and it shows that force-displacement response history of test specimen during HFT can be used in the form of a stiffness update to ensure test stability.

The present study aimed to investigate whether male consumers report weaker green consumption values than their female counterparts, and whether such a presumed sex difference, at least in part, can be explained by different levels of intrasexual competition. In other words, the study tested the notion that intrasexual competition acts as a psychological mechanism explaining why male (vs female) consumers are sometimes less prone to prefer and purchase sustainable goods, with their higher tendency to compete with same-sex rivals making them less likely to engage in green consumption.

The study was based on a large cross-sectional survey, in which a final sample of 1,382 participants (823 female and 559 male) provided complete responses on well-validated scales measuring intrasexual competition and green consumption values. The large sample size implies that even small effect sizes could be detected with high statistical power. The data were analyzed using a series of Mann–Whitney U tests to compare the responses made by male and female participants. Subsequently, multiple linear regressions as well as regression-based mediation and moderation analyses were performed with control variables added to show robustness of the results, test the proposed chain of events, and demonstrate generalizability.

Male (vs female) participants expressed significantly higher levels of intrasexual competition both generally and on the two subdimensions corresponding to superiority striving and inferiority irritation. Further, they were slightly less inclined to express green consumption values. Importantly, the sex difference in green consumption values was mediated by inferiority irritation as well as the entire intrasexual competition scale but not by superiority striving. Thus, men's inferiority irritation, in particular, and their more pronounced propensity to compete with same-sex rivals, in general, drove them away from green consumption, whereas women's weaker willingness to compete with same-sex rivals instead increased their inclination of “going green.”

Drawing on findings from the domains of competitiveness and gender stereotypes, the current research demonstrates a novel mechanism through which green consumption responses can be understood. Specifically, this study provides empirical evidence for the mediating role of intrasexual competition, especially regarding the more negatively charged subdimension of inferiority irritation, in explaining why male and female consumers may differ in terms of their green consumption values. The present research also contributes to the literature by questioning the unidimensional structure of the intrasexual competition scale and showing that the negative (vs positive) subdimension of this scale is more influential in explaining sex-differentiated patterns in consumers' green consumption values, thereby supporting the notion that “bad is stronger than good.”

This research sheds light on behavioral change by demonstrating the transformative power of a brand on the process of eating behavioral change. The selected brand is Three Times a Day (a culinary blog whose mission is to encourage a healthier diet). This study aims to identify food-related behavioral changes as a result of consumers’ relationship with this brand and identify antecedents to such changes.

A netnography of the brand online community and 14 individual in-depth interviews were conducted.

Netnography results identify four categories of behavioral changes emerging from the relationship with the brand (e.g. choosing healthier/more varied foods, developing an interest in cooking and adopting a healthier lifestyle). Analysis of the individual interviews substantiate the role of brand attachment as a driver of positive change and identify three antecedents: brand-self connection (through past, actual and ideal self), brand exposure and satisfaction of individual needs (i.e. autonomy, competence and relatedness).

Results enrich the literature on behavioral change and highlight the positive role of a brand in the context of improving eating habits. Findings extend the understanding of the consequences of attachment beyond its influence at the attitudinal level by focusing on concrete consumer behavior.

It is recognized that despite good intentions, individuals keep making poor food choices. This important issue is associated with several diseases and increasing social costs. This research explores how to influence consumers in adopting better eating habits.

This study is one of the first to examine the power of a food-related brand to enhance positive eating practices and improve diet.

Studies to date have focused on one or very few factors, rather than exploring a host of influences associated with children’s consumption of energy-dense foods. This is surprising as multiple agents are relevant to children’s food consumer socialisation (parents, peers, social norms and food advertising). This study aims to address these gaps and offers the first comprehensive empirical assessment of a wide cluster of variables.

A cross-sectional study was undertaken with children aged 7-13 years and their parents/main carers, collecting family metrics from parents and data directly from children. Structural Equation Modelling was used to estimate a series of interdependence relationships in four steps, revealing the increased explained variance in children’s consumption of energy-dense foods.

The inclusion of multiple potential factors increased the percentage of explained variance in children’s consumption of energy-dense foods. The models explicate which factors relate to frequent consumption in children, and clarify various indirect influences on children through parents.

For the first time, a wider range of variables was integrated to maximise the percentage of explained variance in children’s behaviour, providing policy makers and social marketers with novel insights regarding areas that need to be prioritised for consumer education. Both direct and indirect relationships were assessed. Data were collected from parents and their children to provide an original methodological contribution and richer data for investigation.