Review of current fire design rules for cold-formed steel wall systems

Light gauge steel frame wall systems are commonly used in industrial and commercial buildings, and there is a need for simple fire design rules to predict their load capacities and fire resistance ratings. During fire events, the light gauge steel frame wall studs are subjected to non-uniform temperature distributions that cause thermal bowing, neutral axis shift and magnification effects and thus resulting in a combined axial compression and bending action on the studs. In this research, a series of full-scale fire tests was conducted first to evaluate the performance of light gauge steel frame wall systems with eight different wall configurations under standard fire conditions. Finite element models of light gauge steel frame walls were then developed, analysed under transient and steady-state conditions and validated using full-scale fire tests. Using the results from fire tests and finite element analyses, a detailed investigation was undertaken into the prediction of axial compression strength and failure times of light gauge steel frame wall studs in standard fires using the available fire design rules based on Australian, American and European standards. The results from both fire tests and finite element analyses were used to investigate the ability of these fire design rules to include the complex effects of non-uniform temperature distributions and their accuracy in predicting the axial compression strength of wall studs and the failure times. Suitable modifications were then proposed to the fire design rules. This article presents the details of this investigation on the fire design rules of light gauge steel frame walls and the results.

Development of a simplified design method to predict the fire rating of LSF walls

Recent fire research into the behaviour of light gauge steel frame (LSF) wall systems has devel-oped fire design rules based on Australian and European cold-formed steel design standards, AS/NZS 4600 and Eurocode 3 Part 1.3. However, these design rules are complex since the LSF wall studs are subjected to non-uniform elevated temperature distributions when the walls are exposed to fire from one side. Therefore this paper proposes an alternative design method for routine predictions of fire resistance rating of LSF walls. In this method, suitable equations are recommended first to predict the idealised stud time-temperature pro-files of eight different LSF wall configurations subject to standard fire conditions based on full scale fire test results. A new set of equations was then proposed to find the critical hot flange (failure) temperature for a giv-en load ratio for the same LSF wall configurations with varying steel grades and thickness. These equations were developed based on detailed finite element analyses that predicted the axial compression capacities and failure times of LSF wall studs subject to non-uniform temperature distributions with varying steel grades and thicknesses. This paper proposes a simple design method in which the two sets of equations developed for time-temperature profiles and critical hot flange temperatures are used to find the failure times of LSF walls. The proposed method was verified by comparing its predictions with the results from full scale fire tests and finite element analyses. This paper presents the details of this study including the finite element models of LSF wall studs, the results from relevant fire tests and finite element analyses, and the proposed equations.

Improved design rules for cold-formed steel columns

Current design rules for determining the member strength of cold-formed steel columns are based on the effective length of the member and a single column capacity curve for both pin-ended and fixed-ended columns. This research has reviewed the use of AS/NZS 4600 design rules for their accuracy in determining the member compression capacities of slender cold-formed steel columns using detailed numerical studies. It has shown that AS/NZS 4600 design rules accurately predicted the capacities of pinned and fixed ended columns undergoing flexural buckling. However, for fixed ended columns undergoing flexural-torsional buckling, it was found that current AS/NZS 4600 design rules did not include the beneficial effect of warping fixity. Therefore AS/NZS 4600 design rules were found to be excessively conservative and hence uneconomical in predicting the failure loads obtained from tests and finite element analyses of fixed-ended lipped channel columns. Based on this finding, suitable recommendations have been made to modify the current AS/NZS 4600 design rules to more accurately reflect the results obtained from the numerical and experimental studies conducted in this research. This paper presents the details of this research on cold-formed steel columns and the results.

Improved design rules for fixed ended cold-formed steel columns subject to flexural-torsional buckling

This paper has presented the details of an investigation into the flexural and flexuraltorsional buckling behaviour of cold-formed structural steel columns with pinned and fixed ends. Current design rules for the member capacities of cold-formed steel columns are based on the same non-dimensional strength curve for both fixed and pinned-ended columns. This research has reviewed the accuracy of the current design rules in AS/NZS 4600 and the North American Specification in determining the member capacities of cold-formed steel columns using the results from detailed finite element analyses and an experimental study of lipped channel columns. It was found that the current Australian and American design rules accurately predicted the member capacities of pin ended lipped channel columns undergoing flexural and flexural torsional buckling. However, for fixed ended columns with warping fixity undergoing flexural-torsional buckling, it was found that the current design rules significantly underestimated the column capacities as they disregard the beneficial effect of warping fixity. This paper has therefore proposed improved design rules and verified their accuracy using finite element analysis and test results of cold-formed lipped channel columns made of three cross-sections and five different steel grades and thicknesses.

Experimental studies of the shear behaviour and strength of lipped channel beams with web openings

Cold-formed steel members are increasingly used as primary structural elements in the building industries around the world due to the availability of thin and high strength steels and advanced cold-forming technologies. Cold-formed lipped channel beams (LCB) are commonly used as flexural members such as floor joists and bearers. However, their shear capacities are determined based on conservative design rules. Current practice in flooring systems is to include openings in the web element of floor joists or bearers so that building services can be located within them. Shear behaviour of LCBs with web openings is more complicated while their shear strengths are considerably reduced by the presence of web openings. However, limited research has been undertaken on the shear behaviour and strength of LCBs with web openings. Hence a detailed experimental study involving 40 shear tests was undertaken to investigate the shear behaviour and strength of LCBs with web openings. Simply supported test specimens of LCBs with aspect ratios of 1.0 and 1.5 were loaded at midspan until failure. This paper presents the details of this experimental study and the results of their shear capacities and behavioural characteristics. Experimental results showed that the current design rules in cold-formed steel structures design codes are very conservative for the shear design of LCBs with web openings. Improved design equations have been proposed for the shear strength of LCBs with web openings based on the experimental results from this study.

Improved shear design rules for lipped channel beams with web openings

Cold-formed steel Lipped Channel Beams (LCB) with web openings are commonly used as floor joists and bearers in building structures. The shear behaviour of these beams is more complicated and their shear capacities are considerably reduced by the presence of web openings. However, limited research has been undertaken on the shear behaviour and strength of LCBs with web openings. Hence a detailed numerical study was undertaken to investigate the shear behaviour and strength of LCBs with web openings. Finite element models of simply supported LCBs under a mid-span load with aspect ratios of 1.0 and 1.5 were developed and validated by comparing their results with test results. They were then used in a detailed parametric study to investigate the effects of various influential parameters. Experimental and numerical results showed that the current design rules in cold-formed steel structures design codes are very conservative. Improved design equations were therefore proposed for the shear strength of LCBs with web openings based on both experimental and numerical results. This paper presents the details of finite element modelling of LCBs with web openings, validation of finite element models, and the development of improved shear design rules. The proposed shear design rules in this paper can be considered for inclusion in the future versions of cold-formed steel design codes.

Implementing the self-management threshold learning outcome in Australian legal curricula : insights from self-determination theory

In 2010, six Threshold Learning Outcomes (TLOs) for law were developed by the Australian Learning and Teaching Council's Discipline Scholars: Law. The final of these outcomes, TLO 6, concerns self-management. This thesis examines strategies for implementing self-management in Australian legal education by first contextualising the development of TLO 6 in light of other relevant national and international developments in higher education, and secondly, analysing this learning outcome through the lens of Self-Determination Theory (SDT), an influential branch of educational psychology. It is argued that the central concept of autonomous self-regulation in SDT provides insights into factors that are relevant to law students’ capacities for long-term self-management, which is reinforced by analysis of the literature on law students’ distress. Accordingly, curriculum design that supports students’ autonomy may simultaneously promote students’ self-management capacities. The discussion of theoretical and practical perspectives on autonomy supportive curriculum design in this thesis thus illuminates potential pedagogical approaches for the implementation of TLO 6 in Australian legal curricula.

Evaluating consent and legitimacy amongst shifting community norms : an EVE Online case study

The legitimate resolution of disputes in online environments requires a complex understanding of the social norms of the community. The conventional legal approach to resolving disputes through literal interpretation of the contractual terms of service is highly problematic because it does not take into account potential conflict with community expectations. In this paper we examine the importance of consent to community governance and argue that a purely formal evaluation of consent is insufficient to legitimately resolve disputes. As online communities continue to grow in importance to the lives of their participants, the importance of resolving disputes legitimately, with reference to the consent of the community, will also continue to grow. Real consent, however, is difficult to identify. We present a case study of botting and real money trading in EVE Online that highlights the dynamic interaction of community norms and private governance processes. Through this case study, we argue that the major challenge facing regulators of online environments is that community norms are complex, contested, and continuously evolving. Developing legitimate regulatory frameworks then depends on the ability of regulators to create efficient and acceptable modes of dispute resolution that can take into account (and acceptably resolve) the tension between formal contractual rules and complex and conflicting community understandings of acceptable behaviour.

Auditor obligations in an evolving legal landscape

Purpose – The purpose of this paper is to look at auditor obligations to their clients and potentially to third parties such as investors, with a focus on the quality of financial disclosure in an evolving legal framework. Design/methodology/approach – The article outlines and compares established and emerging trends relative to information disclosure and contractual performance in parallel contexts where information asymmetry exists. In particular, this article considers the disclosure regime that has evolved in the insurance industry to address the substantial imbalance in the level of knowledge possessed by the insured in comparison to the prospective insurer. Abductive reasoning is used to identify causal constructs that explain the data pattern from which the theorised potential for judicial revision of the interpretation of “true and fair” in line with “good faith” in legal regulation is derived. Findings – The authors conclude that there is little doubt that a duty of good faith in relation to auditor-company contractual dealings and potentially a broader good faith duty to third parties such as investors in companies may be on the horizon. Originality/value – In the context of stated objectives by organisations such as the International Federation of Accountants to reconcile ethical and technical skills in the wake of the global financial crisis, there is an increased need to rebuild public and investor confidence in the underpinning integrity of financial reporting. This paper offers a perspective on one way to achieve this by recognising the similarities in the information asymmetry relationships in the insurance industry and how the notion of “good faith” in that relationship could be useful in the audit situation.

Organized crime in Oceania

Oceania has a relatively low level of crime prevalence yet in the smaller and under-developed PICs we have shown that transnational crime has become increasingly common. A risk contained but potentially dangerous if state failure or fragility undermines law enforcement capacities. We predict that as the pace of globalization quickens and the demand for raw materials and resources grows some parts of the Pacific will be prone to criminal enterprises run by both indigenous and foreign crime groups. Australia and New Zealand will remain attractors of illicit goods notably ATS but will in turn be source countries for diminishing fish stock such as beche de mere and abalone as well forest timber. Finally the role of states such as Australia and New Zealand in helping to maintain law enforcement capacities throughout the region will be crucial if organized crime in Oceania is to be kept in check while demand for illicit resources grow.

Transnational organized crime in Oceania

Oceania has a relatively low level of crime prevalence yet in the smaller and under-developed PICs we have shown that transnational crime has become increasingly common. A risk contained but potentially dangerous if state failure or fragility undermines law enforcement capacities. We predict that as the pace of globalization quickens and the demand for raw materials and resources grows some parts of the Pacific will be prone to criminal enterprises run by both indigenous and foreign crime groups. Australia and New Zealand will remain attractors of illicit goods notably ATS but will in turn be source countries for diminishing fish stock such as beche de mere and abalone as well forest timber. Finally the role of states such as Australia and New Zealand in helping to maintain law enforcement capacities throughout the region will be crucial if organized crime in Oceania is to be kept in check while demand for illicit resources grow.

Susceptibility of the critical structural components of railway bridges to the changes in train speed

Modern trains with different axle configurations, speeds and loads are used in railway networks. As a result, one of the most important questions of the mangers involved in bridge managements systems (BMS) is how these changes affect the structural behavior of the critical components of the railway bridges. Although researchers have conducted, many investigations on the dynamic effects of the moving loads on bridges, the influence of the changes in the speed of the train on the demand by capacity ratios of the different critical components of the bridge have not yet been properly studied. This study is important, because different components with different capacities and roles for carrying loads in the structure may be affected differently. To investigate the above phenomenon in this research, a structural model of a simply supported bridge is developed. It will be verified that the dynamic behavior of this bridge is similar to a group of railway bridges in Australia. Demand by capacity ratios of the critical components of the bridge, when it is subjected to a train load with different speeds will be calculated. The results show that the effect of increase or decrease of speed should not be underestimated. The outcome is very significant as it is contrary to what is currently expected, i.e. by reducing the speed of the train, the demand by capacity ratio of components may increase and make the bridge unsafe for carrying live load.

The consequences of not taking reasonable steps to obtain finance

In Hauff v Miller [2013] QCA 48 the Queensland Court of Appeal considered an issue that has not previously arisen at appellate level. The case concerned the interaction of the well-known subject to finance clause and other standard contractual provisions...

Homeostatic epistemology : reliability, coherence and coordination in a Bayesian virtue epistemology

How do agents with limited cognitive capacities flourish in informationally impoverished or unexpected circumstances? Aristotle argued that human flourishing emerged from knowing about the world and our place within it. If he is right, then the virtuous processes that produce knowledge, best explain flourishing. Influenced by Aristotle, virtue epistemology defends an analysis of knowledge where beliefs are evaluated for their truth and the intellectual virtue or competences relied on in their creation. However, human flourishing may emerge from how degrees of ignorance are managed in an uncertain world. Perhaps decision-making in the shadow of knowledge best explains human wellbeing—a Bayesian approach? In this dissertation I argue that a hybrid of virtue and Bayesian epistemologies explains human flourishing—what I term homeostatic epistemology. Homeostatic epistemology supposes that an agent has a rational credence p when p is the product of reliable processes aligned with the norms of probability theory; whereas an agent knows that p when a rational credence p is the product of reliable processes such that: 1) p meets some relevant threshold for belief (such that the agent acts as though p were true and indeed p is true), 2) p coheres with a satisficing set of relevant beliefs and, 3) the relevant set of beliefs is coordinated appropriately to meet the integrated aims of the agent. Homeostatic epistemology recognizes that justificatory relationships between beliefs are constantly changing to combat uncertainties and to take advantage of predictable circumstances. Contrary to holism, justification is built up and broken down across limited sets like the anabolic and catabolic processes that maintain homeostasis in the cells, organs and systems of the body. It is the coordination of choristic sets of reliably produced beliefs that create the greatest flourishing given the limitations inherent in the situated agent.

On facilitating regional integration and economic development with collaborative technologies in the South Pacific

The current global economic instability and the vulnerability of small island nations are providing the impetus for greater integration between the countries of the South Pacific region. This exercise is critical for their survival in today’s turbulent economic environment. Past efforts of regional integration in the South Pacific have not been very successful. Reasons attributed to this outcome include issues related to damage of sovereignty, and lack of a shared integration infrastructure. Today, the IT resources with collaborative capacities provide the opportunity to develop a shared IT infrastructure to facilitate integration in the South Pacific. In an attempt to develop a model of regional integration with an IT-backed infrastructure, we identify and report on the antecedents of the current stage of regional integration, and the stakeholders’ perceived benefits of an IT resources backed regional integration in the South Pacific. Employing a case study based approach, the study finds that while most stakeholders were positive about the potential of IT-backed regional integration, significant challenges exist that hinder the realisation of this model. The study finds that facilitating IT-backed regional integration requires enabling IT infrastructure, equitable IT development in the region, greater awareness on the potential of the modern IT resources, market liberalisation of the information and telecommunications sector and greater political support for IT initiatives.