Dynamic performance characteristics of an innovative Hybrid Composite Floor Plate System under human-induced loads

This study explored the dynamic performance of an innovative Hybrid Composite Floor Plate System (HCFPS), composed of Polyurethane (PU) core, outer layers of Glass–fibre Reinforced Cement (GRC) and steel laminates at tensile regions, using experimental testing and Finite Element (FE) modelling. Experimental testing included heel impact and walking tests for 3200 mm span HCFPS panels. FE models of the HCFPS were developed using the FE program ABAQUS and validated with experimental results. HCFPS is a light-weight high frequency floor system with excellent damping ratio of 5% (bare floor) due to the central PU core. Parametric studies were conducted using the validated FE models to investigate the dynamic response of the HCFPS and to identify characteristics that influence acceleration response under human induced vibration in service. This vibration performance was compared with recommended acceptable perceptibility limits. The findings of this study show that HCFPS can be used in residential and office buildings as a light-weight floor system, which does not exceed the perceptible thresholds due to human induced vibrations.

Numerical studies of load bearing LSF walls under realistic design fire conditions

Fire safety of light gauge steel frame (LSF) stud walls is important in the design of buildings. Currently LSF walls are increasingly used in the building industry, and are usually made of cold-formed and thin-walled steel studs that are fire-protected by two layers of plasterboard on both sides. Many experimental and numerical studies have been undertaken to investigate the fire performance of load bearing LSF walls under standard fire conditions. However, the standard time-temperature curve does not represent the fire load present in typical residential and commercial buildings that include considerable amount of thermoplastic materials. Real building fires are unlikely to follow a standard time-temperature curve. However, only limited research has been undertaken to investigate the fire performance of load bearing LSF walls under realistic design fire conditions. Therefore in this research, finite element thermal models of the traditional LSF wall panels without cavity insulation and the new LSF composite wall panels were developed to simulate their fire performance under recently developed realistic design fire curves. Suitable thermal properties were proposed for plasterboards and insulations based on laboratory tests and literature review. The developed models were then validated by comparing their thermal performance results with available results from realistic design fire tests, and were later used in parametric studies. This paper presents the details of the developed finite element thermal models of load bearing LSF wall panels under realistic design fire time-temperature curves and the re-sults. It shows that finite element thermal models can be used to predict the fire performance of load bearing LSF walls with varying configurations of insulations and plasterboards under realistic design fires. Failure times of load bearing LSF walls were also predicted based on the results from finite element thermal analyses.

Evaluation of shear stress and slip relationship of composite lap joints

Advanced composite materials offer remarkable potential in the strengthening of Civil Engineering structures. This research is targeted to provide in depth knowledge and understanding of bond characteristics of advanced and corrosion resistant material carbon fibre reinforced polymer (CFRP) that has a unique design tailor-ability and cost effective nature. The objective of this research is to investigate and compare the bonding mechanism between CFRP strengthened single and double strap steel joints. Investigations have been made in regards to failure mode, ultimate load and effective bond length for CFRP strengthened double and single strap joints. A series of tensile tests were conducted with different bond lengths for both type of joints. The bond behaviour of these specimens was further investigated by using nonlinear finite element analysis. Finally a bilinear relationship of shear stress-slip has been proposed by using the Finite element model for single and double strap joints.

Multi-objective design optimisation of GFRP sandwich beams

A novel Glass Fibre Reinforced Polymer (GFRP) sandwich panel was developed by an Australian manufacturer for civil engineering applications. This research is motivated by the new applications of GFRP sandwich structures in civil engineering such as slab, beam, girder and sleeper. An optimisation methodology is developed in this work to enhance the design of GFRP sandwich beams. The design of single and glue laminated GFRP sandwich beam were conducted by using numerical optimisation. The numerical multi-objective optimisation considered a design two objectives simultaneously. These objectives are cost and mass. The numerical optimisation uses the Adaptive Range Multi-objective Genetic Algorithm (ARMOGA) and Finite Element (FE) method. Trade-offs between objectives was found during the optimisation process. Multi-objective optimisation shows a core to skin mass ratio equal to 3.68 for the single sandwich beam cross section optimisation and it showed that the optimum core to skin thickness ratio is 11.0.

Safety enhancement of water-filled road safety barrier using interaction of composite materials

Road safety barriers are used to redirect traffic at roadside work-zones. When filled with water, these barriers are able to withstand low to moderate impact speeds up to 50kmh-1. Despite this feature, Portable Water-filled barriers (PWFB) face challenges such as large lateral displacements, tearing and breakage during impact; especially at higher speeds. This study explores the use of composite action to enhance the crashworthiness of PWFBs and enable their usage at higher speeds. Initially, energy absorption capability of water in PWFB is investigated. Then, composite action of the PWFB with the introduction of steel frame is considered to evaluate its enhanced impact performance. Findings of the study show that the initial height of the impact must be lower than the free surface level of water in a PWFB in order for the water to provide significant crash energy absorption. In general, an impact of a road barrier with 80% filled is a good estimation. Furthermore, the addition of a composite structure greatly reduces the probability of tearing by decreasing the strain and impact energy transferred to the shell container. This allows the water to remain longer in the barrier to absorb energy via inertial displacements and sloshing response. Information from this research will aid in the design of new generation roadside safety structures aimed to increase safety in modern roadways.

Alternative structural design strategies for bridge decks in low traffic volume roads

This research is part of a major project with a stimulus that rose from the need to manage a large number of ageing bridges in low traffic volume roads (LTVR) in Australia. The project investigated, designed and consequently constructed, involved replacing an ageing super-structure of a 10m span bridge with a disused Flat-bed Rail Wagon (FRW). This research, therefore, is developed on the premises that the FRW can be adopted as the main structural system for the bridges in LTVR network. The main focus of this research is to present two alternate deck wearing systems (DWS) as part of the design of the FRW as road bridge deck conforming to AS5100 (2004). The bare FRW structural components were first examined for their adequacy (ultimate and serviceability) in resisting the critical loads specified in AS5100(2004). Two options of DWSs were evaluated and their effects on the FRW examined. The first option involved usage of timber DWS; the idea of this option was to use all the primary and secondary members of the FRW in load sharing and to provide additional members where weaknesses in the original members arose. The second option involved usage of reinforced concrete DWS with only the primary members of the FRW sharing the AS5100 (2004) loading. This option inherently minimised the risk associated with any uncertainty of the secondary members to their structural adequacy. This thesis reports the design phases of both options with conclusions of the selection of the ideal option for better structural performance, ease of construction and cost. The comparison carried out here focuses on the distribution of the traffic load by the FRW as a superstructure. Advantages and disadvantages highlighting cost comparisons and ease of constructability of the two systems are also included.

Educating the ‘Design Innovation Catalyst’ for change

Conventionally, design has played a compartmental role in the innovation process within most conservative companies around the world. Generally, companies have focused on the product design execution or the manufacturing and production arenas, and in some instances design is seen as merely a stylistic afterthought. Gradually, design is being regarded as a dynamic and central tactical business resource and consequently organisations globally look to design to help them innovate, differentiate and compete in a changing economic climate. Considering this, the question is raised; how can the specific knowledge and skills of designers be better articulated, understood, implemented and valued as a core component of strategic innovation in businesses? In seeking to answer this question, this paper proposes the new frontier of the design profession coined the ‘Design Innovation Catalyst’. This paper outlines the role of the new design professional and discusses the subsequent implications for design education. Furthermore, questions surrounding how designers will develop these new capabilities and how the design led innovation framework in application can contribute to the future of design will also be presented. It is anticipated that the findings from this research will help to better equip designers to enable them to play a more central role in business and strategic innovation now and in the future.

Safety enhancement of water-filled road safety barrier using interaction of composite materials

Road safety barriers are used to redirect traffic at roadside work-zones. When filled with water, these barriers are able to withstand low to moderate impact speeds up to 50kmh-1. Despite this feature, there are challenges when using portable water-filled barriers (PWFBs) such as large lateral displacements as well as tearing and breakage during impact, especially at higher speeds. In this study, the authors explore the use of composite action to enhance the crashworthiness of PWFBs and enable their use at higher speeds. Initially, we investigated the energy absorption capability of water in PWFB. Then, we considered the composite action of a PWFB with the introduction of a steel frame to evaluate its impact on performance. Findings of the study show that the initial height of impact must be lower than the free surface level of water in a PWFB for the water to provide significant crash energy absorption. In general, impact of a road barrier that is 80% filled is a good estimation. Furthermore, the addition of a composite structure greatly reduces the probability of tearing by decreasing the strain and impact energy transferred to the shell container. This allows the water to remain longer in the barrier to absorb energy via inertial displacement and sloshing response. Information from this research will aid in the design of next generation roadside safety structures aimed to increase safety on modern roadways.

Experimental impact and finite element analysis of a composite, portable road safety barrier

This thesis provides an experimental and computational platform for investigating the performance and behaviour of water filled, plastic portable road safety barriers in an isolated impact scenario. A schedule of experimental impact tests were conducted assessing the impact response of an existing design of road safety barrier utilising a novel horizontal impact testing system. A coupled finite element and smooth particle hydrodynamic model of the barrier system was developed and validated against the results of the experimental tests. The validated model was subsequently used to assess the effect of certain composite materials on the impact performance of the water filled, portable road safety barrier system.

From strategic design to design integration

Within a growing awareness of design as central to the strategic success and the sustained competitive advantage of firms, this paper examines how companies pursue design driven innovation (Verganti, 2008, 2009) and respond to design led innovation initiatives (Matthews & Bucolo 2013). Specifically, this paper reports the findings of a collaborative research project where CEO sponsored senior managers from five multi-national organisations, met regularly over a twelve-month period, to discuss their progress on applying a design led approach in their firms. This longitudinal research project traced the process and progress of change instigated by the senior management representatives, as well as the deeper investigation of the barriers and challenges to re-frame design more strategically in their organisation. Data were collected through workshops and interviews throughout the twelve-month period, regarding the firms’ journeys and also the barriers and challenges firms faced in order to become design led. The findings present a novel set of implications for both designers and management scholars. This paper seeks to contribute to research and practice by investigating the processes and outcomes of a design led innovation program and to propose implications for practice for designers and management.

Photovoltaic DC-DC module integrated converter for novel cascaded and bypass grid connection topologies - design and optimisation

Grid connected photovoltaic (PV) inverters fall into three broad categories - central, string and module integrated converters (MICs). MICs offer many advantages in performance and flexibility, but are at a cost disadvantage. Two alternative novel approaches proposed by the author - cascaded dc-dc MICs and bypass dc-dc MICs - integrate a simple non-isolated intelligent dc-dc converter with each PV module to provide the advantages of dc-ac MICs at a lower cost. A suitable universal 150 W 5 A dc-dc converter design is presented based on two interleaved MOSFET half bridges. Testing shows zero voltage switching (ZVS) keeps losses under 1 W for bi-directional power flows up to 15 W between two adjacent 12 V PV modules for the bypass application, and efficiencies over 94% for most of the operational power range for the cascaded converter application. Based on the experimental results, potential optimizations to further reduce losses are discussed.

Protocol for a randomised blocked design study using telephone and text-messaging to support cardiac patients with diabetes : a cross cultural international collaborative project

Background The prevalence of type 2 diabetes is rising internationally. Patients with diabetes have a higher risk of cardiovascular events accounting for substantial premature morbidity and mortality, and health care expenditure. Given healthcare workforce limitations, there is a need to improve interventions that promote positive self-management behaviours that enable patients to manage their chronic conditions effectively, across different cultural contexts. Previous studies have evaluated the feasibility of including telephone and Short Message Service (SMS) follow up in chronic disease self-management programs, but only for single diseases or in one specific population. Therefore, the aim of this study is to evaluate the feasibility and short-term efficacy of incorporating telephone and text messaging to support the care of patients with diabetes and cardiac disease, in Australia and in Taiwan. Methods/design A randomised controlled trial design will be used to evaluate a self-management program for people with diabetes and cardiac disease that incorporates the use of simple remote-access communication technologies. A sample size of 180 participants from Australia and Taiwan will be recruited and randomised in a one-to-one ratio to receive either the intervention in addition to usual care (intervention) or usual care alone (control). The intervention will consist of in-hospital education as well as follow up utilising personal telephone calls and SMS reminders. Primary short term outcomes of interest include self-care behaviours and self-efficacy assessed at baseline and four weeks. Discussion If the results of this investigation substantiate the feasibility and efficacy of the telephone and SMS intervention for promoting self management among patients with diabetes and cardiac disease in Australia and Taiwan, it will support the external validity of the intervention. It is anticipated that empirical data from this investigation will provide valuable information to inform future international collaborations, while providing a platform for further enhancements of the program, which has potential to benefit patients internationally.

An examination of learning design in elite springboard diving

The overarching aim of this programme of work was to evaluate the effectiveness of the existing learning environment within the Australian Institute of Sport (AIS) elite springboard diving programme. Unique to the current research programme, is the application of ideas from an established theory of motor learning, specifically ecological dynamics, to an applied high performance training environment. In this research programme springboard diving is examined as a complex system, where individual, task, and environmental constraints are continually interacting to shape performance. As a consequence, this thesis presents some necessary and unique insights into representative learning design and movement adaptations in a sample of elite athletes. The questions examined in this programme of work relate to how best to structure practice, which is central to developing an effective learning environment in a high performance setting. Specifically, the series of studies reported in the chapters of this doctoral thesis: (i) provide evidence for the importance of designing representative practice tasks in training; (ii) establish that completed and baulked (prematurely terminated) take-offs are not different enough to justify the abortion of a planned dive; and (iii), confirm that elite athletes performing complex skills are able to adapt their movement patterns to achieve consistent performance outcomes from variable dive take-off conditions. Chapters One and Two of the thesis provide an overview of the theoretical ideas framing the programme of work, and include a review of literature pertinent to the research aims and subsequent empirical chapters. Chapter Three examined the representativeness of take-off tasks completed in the two AIS diving training facilities routinely used in springboard diving. Results highlighted differences in the preparatory phase of reverse dive take-offs completed by elite divers during normal training tasks in the dry-land and aquatic training environments. The most noticeable differences in dive take-off between environments began during the hurdle (step, jump, height and flight) where the diver generates the necessary momentum to complete the dive. Consequently, greater step lengths, jump heights and flight times, resulted in greater board depression prior to take-off in the aquatic environment where the dives required greater amounts of rotation. The differences observed between the preparatory phases of reverse dive take-offs completed in the dry-land and aquatic training environments are arguably a consequence of the constraints of the training environment. Specifically, differences in the environmental information available to the athletes, and the need to alter the landing (feet first vs. wrist first landing) from the take-off, resulted in a decoupling of important perception and action information and a decomposition of the dive take-off task. In attempting to only practise high quality dives, many athletes have followed a traditional motor learning approach (Schmidt, 1975) and tried to eliminate take-off variations during training. Chapter Four examined whether observable differences existed between the movement kinematics of elite divers in the preparation phases of baulked (prematurely terminated) and completed take-offs that might justify this approach to training. Qualitative and quantitative analyses of variability within conditions revealed greater consistency and less variability when dives were completed, and greater variability amongst baulked take-offs for all participants. Based on these findings, it is probable that athletes choose to abort a planned take-off when they detect small variations from the movement patterns (e.g., step lengths, jump height, springboard depression) of highly practiced comfortable dives. However, with no major differences in coordination patterns (topology of the angle-angle plots), and the potential for negative performance outcomes in competition, there appears to be no training advantage in baulking on unsatisfactory take-offs during training, except when a threat of injury is perceived by the athlete. Instead, it was considered that enhancing the athletes' movement adaptability would be a more functional motor learning strategy. In Chapter Five, a twelve-week training programme was conducted to determine whether a sample of elite divers were able to adapt their movement patterns and complete dives successfully, regardless of the perceived quality of their preparatory movements on the springboard. The data indeed suggested that elite divers were able to adapt their movements during the preparatory phase of the take-off and complete good quality dives under more varied take-off conditions; displaying greater consistency and stability in the key performance outcome (dive entry). These findings are in line with previous research findings from other sports (e.g., shooting, triple jump and basketball) and demonstrate how functional or compensatory movement variability can afford greater flexibility in task execution. By previously only practising dives with good quality take-offs, it can be argued that divers only developed strong couplings between information and movement under very specific performance circumstances. As a result, this sample was sometimes characterised by poor performance in competition when the athletes experienced a suboptimal take-off. Throughout this training programme, where divers were encouraged to minimise baulking and attempt to complete every dive, they demonstrated that it was possible to strengthen the information and movement coupling in a variety of performance circumstances, widening of the basin of performance solutions and providing alternative couplings to solve a performance problem even when the take-off was not ideal. The results of this programme of research provide theoretical and experimental implications for understanding representative learning design and movement pattern variability in applied sports science research. Theoretically, this PhD programme contributes empirical evidence to demonstrate the importance of representative design in the training environments of high performance sports programmes. Specifically, this thesis advocates for the design of learning environments that effectively capture and enhance functional and flexible movement responses representative of performance contexts. Further, data from this thesis showed that elite athletes performing complex tasks were able to adapt their movements in the preparatory phase and complete good quality dives under more varied take-off conditions. This finding signals some significant practical implications for athletes, coaches and sports scientists. As such, it is recommended that care should be taken by coaches when designing practice tasks since the clear implication is that athletes need to practice adapting movement patterns during ongoing regulation of multi-articular coordination tasks. For example, volleyball servers can adapt to small variations in the ball toss phase, long jumpers can visually regulate gait as they prepare for the take-off, and springboard divers need to continue to practice adapting their take-off from the hurdle step. In summary, the studies of this programme of work have confirmed that the task constraints of training environments in elite sport performance programmes need to provide a faithful simulation of a competitive performance environment in order that performance outcomes may be stabilised with practice. Further, it is apparent that training environments can be enhanced by ensuring the representative design of task constraints, which have high action fidelity with the performance context. Ultimately, this study recommends that the traditional coaching adage 'perfect practice makes perfect", be reconsidered; instead advocating that practice should be, as Bernstein (1967) suggested, "repetition without repetition".

Design and flight testing of an integrated solar powered UAV and WSN for remote gas sensing

This paper describes a generic and integrated solar powered remote Unmanned Air Vehicles (UAV) and Wireless Sensor Network (WSN) gas sensing system. The system uses a generic gas sensing system for CH4 and CO2 concentrations using metal oxide (MoX) and non-dispersive infrared sensors, and a new solar cell encapsulation method to power the UASs as well as a data management platform to store, analyse and share the information with operators and external users. The system was successfully field tested at ground and low altitudes, collecting, storing and transmitting data in real time to a central node for analysis and 3D mapping. The system can be used in a wide range of outdoor applications, especially in agriculture, bushfires, mining studies, opening the way to a ubiquitous low cost environmental monitoring. A video of the bench and flight test performed can be seen in the following link https://www.youtube.com/watch?v=Bwas7stYIxQ.

Assessing land-use and transport integration via a spatial composite indexing model

Achieving sustainable urban development is identified as one ultimate goal of many contemporary planning endeavours and has become central to formulation of urban planning policies. Within this concept, land-use and transport integration is highlighted as one of the most important and attainable policy objectives. In many cities, integration is embraced as an integral part of local development plans, and a number of key integration principles are identified. However, the lack of available evaluation methods to measure extent of urban sustainability levels prevents successful implementation of these principles. This paper introduces a new indicator-based spatial composite indexing model developed to measure sustainability performance of urban settings by taking into account land-use and transport integration principles. Model indicators are chosen via a thorough selection process in line with key principles of land-use and transport integration. These indicators are grouped into categories and themes according to their topical relevance. These indicators are then aggregated to form a spatial composite index to portray an overview of the sustainability performance of the pilot study area used for model demonstration. The study results revealed that the model is a practical instrument for evaluating success of local integration policies and visualizing sustainability performance of built environments and useful in both identifying problematic areas as well as formulating policy interventions.