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This paper aims to describe coupon tests performed at elevated temperatures on S355 to S500 steel grades and comparison of test results with previous research studies and current EN 1993-1-2 material laws. The objective is to state if these steel grades satisfy to the current material laws and if the scope of application of these laws could be extended to S500 grades.

Two experimental programmes were launched to investigate the behaviour of S460M and S500M steel grades developed for hot-rolled sections. The first research programme was focussed on a comparison between S355 and S460 grades, where the second experimental programme was focussed on the recently developed S500M steel grade. The latter one comprised steady-state tests, transient-state tests and two large-scale beam tests.

Results of steady-state and transient-state tests correlate well with the reduction factors defined in EN 1993-1-2, currently limited to S460 grade. On the basis of this study, the scope of EN 1993-1-2 applies to S500 grades. For steady-state tests, the testing procedure (with and without acceleration after Rp0,2) led to noticeable differences. Transient-state tests, which are not standardised up to now, have been performed considering 5 K/min and 10 K/min constant heating rates. The slowest rate leads to lower strengths as creep effects are more significant. However, all the results are in line with EN 1993-1-2 material law. Importance should be given to the reference yield strength of steel at ambient temperature.

The revision of EN 1993-1-2 is on-going and this piece of work provides a contribution for extending the scope of application of material law of steel under fire conditions.

In recent times, the use of steel sections with web openings has become common as slim floor beams because they offer a reduction in weight of the steelwork, accommodate services within the floor depth and provide the composite action. The composite action in these beams is achieved either through the concrete dowels or through concrete plugs. Though these web openings offer several benefits in slim floor beams, they induce the material discontinuity in the steel web, which may affect their shear capacity and/or thermal behaviour. The purpose of this study is to investigate the thermal behaviour of slim floor beams with web openings in fire.

This research presents findings from experimental and analytical investigations conducted to study the thermal behaviour of slim floor beams with web openings in fire. For this purpose, an experimental investigation was conducted, which shows that the presence of web openings has a major influence on temperature development across the steel section as well as along the span of these beams. The behaviour of the tested slim floor beam is validated using finite element modelling. The validated finite element model is then used to conduct a sensitivity study to analyse the influence of different opening spacings, sizes and shapes on the thermal performance of slim floor beams in fire.

Test results show that the presence of web openings has a major influence on temperature development across the steel section as well as along the span of these beams. Temperatures on the web below the openings are found to be higher as compared to those recorded on the adjacent solid steel web. It is also observed that temperatures on the steel web above the openings are lesser than those on the adjacent solid steel web. Parametric studies conducted using the verified analytical modelling methods show that different opening spacings, sizes and shapes have a variable impact on the thermal behaviour of slim floor beams in fire. Closely spaced and larger opening sizes were found to have a more severe influence on their thermal behaviour in fire as compared to widely spaced and smaller openings. It was also found that the behaviour of these beams is influenced by the shape of the openings with rectangular openings resulting in more severe thermal distributions as compared to circular openings.

The findings from this research study are highly valuable as they contribute to the existing knowledge database. There is a lack of experimental and analytical investigation on performance of slim floor beams with web openings at elevated temperatures. The results and conclusions from this study will help in developing innovative designs for slim floor beams and will help in reducing the fire related risk associated with structures comprising of slim floor beams with web openings.

Virtual grocery shopping (VGS), or online grocery shopping, traditionally has seen slow adoption in Canada; however, the COVID-19 pandemic has forced consumers to seek safer ways to shop. Retailers have invested in building new infrastructure to meet the current consumer demands for VGS. However, the main driver for VGS behaviour has not been yet clearly identified. Additionally, it is also not unknown whether the shopping modalities will continue VGS after the pandemic. This study provides insights into consumer intentions to use VGS by extending the model of goal-directed behaviour (MGB) to incorporate consumer technological readiness.

The study collected 935 valid survey responses from an online survey panel of Canadian consumers. A two-step approach was applied to analyse the data, comprising confirmatory factor analysis (CFA) and structural equation modelling (SEM). The data quality and model fit were tested before testing the proposed relationships among the constructs: attitude, subjective norm, perceived behavioural control, positive and negative anticipated emotions, as well as technological readiness, desire and behaviour intentions. The mediation role of desire between frequency of past online grocery shopping behaviours and the future behavioural intention was also tested using SPSS PROCESS.

The study results showed that attitudes, subjective norms, perceived behavioural control, positive and negative emotions, technological readiness and frequency of past VGS have a major impact on consumers' desire to embrace VGS in the future. Consumer desire also played a significant mediating role between frequency of past VGS behaviours and future shopping intention online. In addition, the frequency of past VGS showed an even stronger impact on behavioural intention among female consumers than among male consumers.

The findings of this study provide an original insight into the social, cultural and psychological factors that impact consumers' use of VGS, particularly the impacts of gender.