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This review paper seeks to enhance knowledge of how pre-loading affects reinforced concrete (RC) beams under fire. It investigates key factors like deflection and load capacity to understand pre-loading's role in replicating RC beams' actual responses to fire, aiming to improve fire testing protocols and structural fire engineering design.

This review systematically aggregates data from existing literature on the fire response of RC beams, comparing scenarios with (WP) and without pre-loading (WOP). Through statistical tools like the two-tailed t-test and Mann–Whitney U-test, it assesses deflection extremes. The study further examines structural responses, including flexural and shear behavior, ultimate load capacity, post-yield behavior, stiffness degradation and failure modes. The approach concludes with a statistical forecast of ideal pre-load levels to elevate experimental precision and enhance fire safety standards.

The review concludes that pre-loading profoundly affects the fire response of RC beams, suggesting a 35%–65% structural capacity range for realistic simulations. The review also recommended the initial crack load as an alternative metric for determining the pre-loading impact. Crucially, it highlights that pre-loading not only influences the fire response but also significantly alters the overall structural behavior of the RC beams.

The review advances structural fire engineering with an in-depth analysis of pre-loading's impact on RC beams during fire exposure, establishing a validated pre-load range through thorough statistical analysis and examination of previous research. It refines experimental methodologies and structural design accuracy, ultimately bolstering fire safety protocols.

Recent research (Barton and Husk, 2012) suggested that in the UK we are seeing a shift from the traditional “pub-club” drinking pattern to a “home-pub-club” pattern. In the latter model often excessive early evening drinking is occurring in the private sphere in the absence of external control, leading to problems when the drinkers enter the public sphere. Moreover, pre-loading has become a key aspect in the drinking patterns of many of the Night Time Economy (NTE) population with around 60-70 per cent of people drinking some alcohol prior to going out. In the previous work (Barton and Husk, 2012) 50 per cent of people were drinking significant quantities of alcohol prior to entering the NTE. The paper aims to discuss these issues.

However, whilst these statistics give a general overview of patterns of drinking, they fail to provide the depth required to uncover potential mechanisms. It is generally assumed that the driving force behind this cultural shift in alcohol use is price. However, the feeling is that this is too simplistic. To explore this, the authors conducted a set of in-depth qualitative interviews with young people to ascertain why pre-loading is such an entrenched aspect of their drinking culture (n=20).

This paper provides the preliminary findings of that research. It shows, amongst other things, that beyond the price factor many young people seemingly need alcohol to cope with the NTE; that they prefer the safety and control of the environment that drinking in the private sphere provides; and that some of them (despite drinking alcohol) simply do not like pubs.

The paper adds to the discourse on pre-loading by suggesting richly described underlying mechanisms of action.

This paper aims to investigate the performance and positioning accuracy of computer numerical controlled (CNC) feed drive system using a ball screw-based pre-loading impact factor.

Initially, axial displacement of support bearings has been computed in relation to the different preload values. Among the computed values, a basic rule equation has been developed for the calculation of elongation in the bearings. The value of displacements computed from the developed equation has been considered as a pre-loading value, and its behavior on the feed drive system has been analyzed.

The elongation of bearings impacts the positioning accuracy and repeatability of the feed drive system and of CNC machines. Next, an analytical model for the rigorous assessment of CNC feed drive system has been designed and developed. The positioning accuracy of CNC machine in relation with different pre-loading values has been analyzed.

The results obtained from these investigations enhance the positioning accuracy of CNC machining centers. The optimum pre-loading value has been analyzed among the available ranges, and it has been proposed that optimal results have been achieved at 5 per cent of dynamic load rating.

This paper proposes improved explorations toward the performance of the CNC machines by optimizing the positioning accuracy through pre-loading. Finally, analytical estimations have been carried out to prove the validity of the proposal.

Since it is necessary to ensure that the operational benefits from pre‐loading are not outweighed by the cost of its introduction, the first part of this article is devoted to the development of an algebraic expression which provides a rule for assessing the desirability of pre‐loading. There follows an empirical examination of the economic effectiveness of pre‐loading, as practised within the UK distribution industry. The conclusion is that industry is using pre‐loading as an effective measure to reduce warehouse staff costs.

The aim of this paper is to focus on the impact of alcohol pre‐loading on behaviour in the night time economy (NTE).

The project was commissioned by Devon and Cornwall Police. During the course of six months in late 2010/early 2011, 597 arrestees were asked a series of questions relating to their drinking patterns on the evening prior to their arrest.

The research shows that there is a shift from the traditional “pub‐club” drinking pattern to a “home‐pub‐club” pattern where excessive early evening drinking is occurring in the private sphere in the absence of external control. Moreover, pre‐loading has become a key aspect in the drinking patterns of many of the NTE population with around 50 per cent of people drinking significant quantities of alcohol prior to entering the NTE. It also demonstrates that those that pre‐load self‐report higher levels of drinking and thus higher levels of intoxication than those that do not.

Findings are constrained by sample bias, as all informants came from the criminal justice system.

When looking specifically at the relationship between pre‐loading and violence, the research showed that there is a relationship between high levels of self‐reported intoxication and self‐reported feelings of aggression, especially in males. This manifested in the NTE as flash points which seemed to occur at entry points to pubs and clubs. Those pre‐loaders that were arrested for violent crimes cite excessive drinking as the significant factor in their behaviour. The research concludes that pre‐loading alcohol prior to entering the NTE is a major challenge to those charged with keeping order in and around city centre pubs and clubs.

The paper adds to the discourse on alcohol related violence in the night time economy, and the negative consequences of pricing drinkers out of licensed premises.

The study aims to investigate the effects of pre-loading histories (pre-shearing and pre-consolidation) on the liquefaction behaviour of saturated loose sand via discrete element method (DEM) simulations.

The pre-shearing history is mimicked under drained conditions (triaxial compression) with different pre-shearing strain levels ranging from 0% to 2%. The pre-consolidation history is mimicked by increasing the isotropic compression to different levels ranging from 100 kPa to 300 kPa. The macroscopic and microscopic behaviours are analysed and compared.

Temporary liquefaction, or quasi-steady state (QSS), is observed in most samples. A higher pre-shearing or pre-consolidation level can provide higher liquefaction resistance. The ultimate state line is found to be unique and independent of the pre-loading histories in stress space. The Lade instability line prematurely predicts the onset of liquefaction for all samples, both with and without pre-loading histories. The redundancy index is an effective microscopic indicator to monitor liquefaction, and the onset of the liquefaction corresponds to the phase transition state where the value of redundancy index is one, which is true for all cases irrespective of the proportions of sliding contacts.

The liquefaction behaviour of granular materials still remains elusive, especially concerning the effects of pre-loading histories on soils. Furthermore, the investigation of the effects of pre-consolidation histories on undrained behaviour and its comparison to pre-sheared samples is rarely reported in the DEM literature.

Over the last decades, self-healing materials based on polymers are attracting increasing interest due to their potential for detecting and “autonomically” healing damage. The use of embedded self-healing microcapsules represents one of the most popular self-healing concepts. Yet, extensive investigations are still needed to convince on the efficiency of the above concept. The paper aims to discuss these issues.

In the present work, the effect of embedded self-healing microcapsules on the ILSS behavior of carbon fiber reinforced composite materials has been studied. Moreover, the self-healing efficiency has been assessed. The results of the mechanical tests were discussed supported by scanning electron microscope (SEM) as well as by Attenuated Total Reflection–Fourier-transform infrared spectroscopy (ATR–FTIR) analyses.

The results indicate a general trend of a degraded mechanical behavior of the enhanced materials, as the microcapsules exhibit a non-uniform dispersion and form agglomerations which act as internal defects. A remarkable value of the self-healing efficiency has been found for materials with limited damage, e.g. matrix micro-cracks. However, for significant damage, in terms of large matrix cracks and delaminations as well as fiber breakages, the self-healing efficiency is limited.

The results obtained by SEM analysis as well as by ATR–FTIR spectroscopy constitute a strong indication that the self-healing mechanism has been activated. However, further investigation should be conducted in order to provide definite evidence.

Tolerance simulation’s reliability depends on the concordance between the input probability distribution and the real variation. The prescribed clamp force introduced changes in parts’ variation, which should be reflected in the input probability distribution for the tolerance simulation. The paper aims to present a tolerance analysis process of the composite wingbox assembly considering the preloading-modified distribution and especially focuses on the spring-in deviation of the thin-walled C-section composite beam (TC2B).

Based on finite element analysis model of TC2B, the preloading-modified probability distribution function (PDF) of the spring-in deviation is obtained. Thickness variations of the TC2B are obtained from the data of the downscaled composite wingbox. These variations are input to the computer-aided tolerance tools, and the final assembly variations are obtained. The assembly of the downscaled wingbox illustrates the effect of preloading on the probability distribution of the spring-in deviation.

The results have shown that the final assembly variations estimated with the modified probability distribution is more reliable than the variation of the initial normal distribution.

The tolerance simulation work presented in the paper will enhance the understanding of the composite parts assembling with spring-in deviations, improve the chance to choose assembling processes that allow specifications to be met and help with tolerance allocation in composites assembly.

The last decade has been a period of considerable change for physical distribution in the UK. Major restructuring has been overdue, often because companies have in the past failed to appreciate the importance of distribution in the marketing process, but now there is a new awareness of the crucial role that distribution can play in the success of companies. As a consequence, innovation in distribution is taking place at an accelerating rate.

This paper aims to investigate how the 18‐ to 30‐age group currently interacts with wine in a variety of settings. It seeks to establish how young adults in the UK currently perceive, use, purchase and consume wine. This is the next generation of UK wine consumers.

A total of seven focus groups were held throughout England and Wales. Participants were between the ages of 18‐30 and consumed wine. A gender balance reflecting UK wine consumption patterns was maintained. One focus group was run to incorporate atypical young wine consumers.

Wine is for sharing but a bottle is too big for one person. This key result influences behaviours; younger adults may not buy wine, especially in the on‐trade, but with age this inclusivity increased consumption with partners and friends. Paradoxically, whilst the public image of wine remains as a civilised cultured beverage, it is often consumed during heavy drinking sessions in private situations. In addition, young adult consumers may not actually know how much they spend on wine, but use media to suggest suitable prices in public forums.

The sample population used was small and may not be representative quantitatively. However, the use of focus groups enabled the gathering of significant qualitative data.

The 18‐ to 30‐age cohort is smaller than the 45 to 64s, who currently consume the most wine. Understanding how this population interacts with wine, identifying potential new markets, may enable the wine and hospitality industries to react effectively to their needs.

Understanding how young adults interact with wine rather than their parents will increase understanding of changing behaviours in relation to the social usage of wine.