947 resultados para Building engineering
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Differential axial shortening, distortion and deformation in high rise buildings is a serious concern. They are caused by three time dependent modes of volume change; “shrinkage”, “creep” and “elastic shortening” that takes place in every concrete element during and after construction. Vertical concrete components in a high rise building are sized and designed based on their strength demand to carry gravity and lateral loads. Therefore, columns and walls are sized, shaped and reinforced differently with varying concrete grades and volume to surface area ratios. These structural components may be subjected to the detrimental effects of differential axial shortening that escalates with increasing the height of buildings. This can have an adverse impact on other structural and non-structural elements. Limited procedures are available to quantify axial shortening, and the results obtained from them differ because each procedure is based on various assumptions and limited to few parameters. All these prompt to a need to develop an accurate numerical procedure to quantify the axial shortening of concrete buildings taking into account the important time varying functions of (i) construction sequence (ii) Young’s Modulus and (iii) creep and shrinkage models associated with reinforced concrete. General assumptions are refined to minimize variability of creep and shrinkage parameters to improve accuracy of the results. Finite element techniques are used in the procedure that employs time history analysis along with compression only elements to simulate staged construction behaviour. This paper presents such a procedure and illustrates it through an example. Keywords: Differential Axial Shortening, Concrete Buildings, Creep and Shrinkage, Construction Sequence, Finite Element Method.
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PROJECT BRIEF Information provided by the Built Environment Industry Innovation Council as background to this project includes the following information on construction and innovation within the industry. • The construction industry contributes around $67 billion to GDP and employs around 970,000 and generates exports of nearly $150 million. • The industry has one of the lowest innovation rates of any industry in Australia, ranking third last across all Australian industries in terms of its proportion of business expenditure on innovation, and second last in terms of the proportion of income generated from innovation (ABS, 2006). • Key innovation challenges include addressing energy and water use efficiency, and housing costs in preparing for the implementation of the Carbon Pollution Reduction Scheme. The sector will need to build its capability and capacity to deliver the technical and operational expertise required.The broader Built Environment Innovation Project aims to address the following two objectives: 1. Identify current innovative practice across the Built Environment industry. 2. Develop a knowledge exchange strategy for this information to be disseminated to all industry stakeholders. Industry practice issues are critical to the built environment industry’s ability to innovate, and the BRITE project from the CRC for Construction Innovation has previously undertaken work to identify the key factors that drive innovation. Part 1 of the current project aims to extend this work by conducting a stocktake of current and emerging innovative practices within the built environment industry. Part 2 of the project addresses the second of these objectives, that is, to recommend a knowledge exchange strategy for promoting the wider uptake of innovative practices that makes the information identified in Part 1 of the study (on emerging innovative practices) accessible to Australian built environment industry stakeholders. The project brief was for the strategy to include a mechanism to enable this information resource to be updated as new initiatives/practices are developed. A better understanding of the built environment industry’s own knowledge infrastructure also has the potential to enhance innovation outcomes for the industry. This project will develop a coordinated knowledge exchange strategy, informed by the best available information on current innovation practices within the industry and suggest directions for gaining a better understanding of: the industry contexts that lead to innovative practices; the industry (including enterprise and individual) drivers for innovation; and appropriate knowledge exchange pathways for delivering future industry innovation. A deliverable of Part 2 will be a recommendation for a knowledge exchange strategy to accelerate adoption of innovative practices in the built environment industry, including resource implications and how such a recommendation could be taken forward as an ongoing resource.
A research framework to investigate the performance of financial incentives in construction projects
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This paper discusses the issues with sharing information between different disciplines in collaborative projects. The focus is on the information itself rather than the wider issues of collaboration. A range of projects carried out by the Cooperative Research Centre for Construction Innovation (CRC CI) in Australia is used to illustrate the issues.
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Recent theoretical work has suggested “entrepreneurial capabilities” themselves may provide the resource foundations to deliver competitive advantage for entrepreneurial firms. This paper empirically examines how start-ups use such entrepreneurial capabilities to build competitive advantage. We investigate the effects of technological and marketing expertise, knowledge of market trends, flexibility and networking on the ability to obtain a cost leadership or differentiation advantage. Using a large dataset of 1,108 start-ups obtained after random sampling of over 30,193 households, we find that differentiation strategies benefit from most resource advantages. Cost leadership strategies, however, seem only to benefit from technological expertise and flexibility and not related to market-based advantages. By doing so, this study contributes to both entrepreneurship and RBV-theories by showing how entrepreneurial capabilities lead to competitive advantages in nascent and early-stage start-ups.
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The current policy decision making in Australia regarding non-health public investments (for example, transport/housing/social welfare programmes) does not quantify health benefits and costs systematically. To address this knowledge gap, this study proposes an economic model for quantifying health impacts of public policies in terms of dollar value. The intention is to enable policy-makers in conducting economic evaluation of health effects of non-health policies and in implementing policies those reduce health inequalities as well as enhance positive health gains of the target population. Health Impact Assessment (HIA) provides an appropriate framework for this study since HIA assesses the beneficial and adverse effects of a programme/policy on public health and on health inequalities through the distribution of those effects. However, HIA usually tries to influence the decision making process using its scientific findings, mostly epidemiological and toxicological evidence. In reality, this evidence can not establish causal links between policy and health impacts since it can not explain how an individual or a community reacts to changing circumstances. The proposed economic model addresses this health-policy linkage using a consumer choice approach that can explain changes in group and individual behaviour in a given economic set up. The economic model suggested in this paper links epidemiological findings with economic analysis to estimate the health costs and benefits of public investment policies. That is, estimating dollar impacts when health status of the exposed population group changes by public programmes – for example, transport initiatives to reduce congestion by building new roads/ highways/ tunnels etc. or by imposing congestion taxes. For policy evaluation purposes, the model is incorporated in the HIA framework by establishing association among identified factors, which drive changes in the behaviour of target population group and in turn, in the health outcomes. The economic variables identified to estimate the health inequality and health costs are levels of income, unemployment, education, age groups, disadvantaged population groups, mortality/morbidity etc. However, though the model validation using case studies and/or available database from Australian non-health policy (say, transport) arena is in the future tasks agenda, it is beyond the scope of this current paper.
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Since 1995 the buildingSMART International Alliance for Interoperability (buildingSMART)has developed a robust standard called the Industry Foundation Classes (IFC). IFC is an object oriented data model with related file format that has facilitated the efficient exchange of data in the development of building information models (BIM). The Cooperative Research Centre for Construction Innovation has contributed to the international effort in the development of the IFC standard and specifically the reinforced concrete part of the latest IFC 2x3 release. Industry Foundation Classes have been endorsed by the International Standards Organisation as a Publicly Available Specification (PAS) under the ISO label ISO/PAS 16739. For more details, go to http://www.tc184- sc4.org/About_TC184-SC4/About_SC4_Standards/ The current IFC model covers the building itself to a useful level of detail. The next stage of development for the IFC standard is where the building meets the ground (terrain) and with civil and external works like pavements, retaining walls, bridges, tunnels etc. With the current focus in Australia on infrastructure projects over the next 20 years a logical extension to this standard was in the area of site and civil works. This proposal recognises that there is an existing body of work on the specification of road representation data. In particular, LandXML is recognised as also is TransXML in the broader context of transportation and CityGML in the common interfacing of city maps, buildings and roads. Examination of interfaces between IFC and these specifications is therefore within the scope of this project. That such interfaces can be developed has already been demonstrated in principle within the IFC for Geographic Information Systems (GIS) project. National road standards that are already in use should be carefully analysed and contacts established in order to gain from this knowledge. The Object Catalogue for the Road Transport Sector (OKSTRA) should be noted as an example. It is also noted that buildingSMART Norway has submitted a proposal
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After many years of development BIM (Building Information Modelling) is starting to achieve significant penetration into the building sector of the construction industry. This paper describes the current status of BIM and the drivers that are motivating the change from 2D CAD to BIM within the building sector. The paper then discusses what the implications of the technology underlying BIM may be for the civil construction sector of the construction industry. A project carried out by the Cooperative Research Centre for Construction Innovation is used as an example of this technology as well as several international examples.
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"This book investigates the origins and implications of the securitization crisis, described by the chief executive of ANZ as a "financial services bloodbath". Based on extensive interviews it offers an integrated series of case studies drawn from the United States, the United Kingdom and Australia. A central purpose is to not only chart what went wrong with the investment houses and why the regulatory systems failed, but also provide policy guidance. The book therefore combines the empirical with the normative. In so doing, it provides a route map to navigate one of the most significant financial and regulatory failures in modern times."
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The research landscape is changing rapidly, and as a consequence the roles of libraries and librarians in supporting and working with researchers is also changing. Some of the drivers behind the changes in research practices and culture include: new technologies, government funding and measurement of research impact, and the importance of open access to data. In Australia, librarians work with researchers to help them identify high quality resources, increase their publication rate and manage and promote access to their research. QUT Library has established a number of initiatives to support researchers, including: establishment of the QUT digital repository ‘ePrints’; purchase of electronic books and electronic journals; programmes of workshops for researchers ; redesign of Library space and, and the creation of new staffing positions. The creation of the QUT ePrints repository was a major new initiative for the QUT Library. ePrints is a web-accessible repository of research outputs created for QUT staff and postgraduate students. The ePrints information is harvested by Google, and anyone searching for a QUT staff member on Google can find their publications listed in ePrints. This keynote address will discuss the context for the role of libraries in building research endeavours, highlight some examples of strategies and resources to supporting researchers. It will conclude with an outline of some key online resources for researchers in education. This presentation should be relevant for both individual researchers interested in conducting and promoting their own research, and for staff and organisations focused on building their support for research.
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As part of a decision making process, the controlling process in construction companies can be supported by computer application that provides faster and reliable decision. This paper discusses the development of a knowledge-based decision support system for controlling construction companies’ business performance. The knowledge-base was developed using questionnaire survey and case studies. A questionnaire survey was conducted to identify potential problems that can occur in construction companies as well as the source of the problems and their impact on companies’ performance. Case studies were used to identify and analyse various corrective actions. The result of the study shows that decision support system using knowledge-based management system improves the effectiveness and the efficiency of decision making process for selecting the most appropriate corrective action that can improve construction companies’ performance. The application, which had been developed in this research, was designed to support the process of controlling construction companies’ business performance and to assist young manager in selecting the most optimum corrective actions for the problems related to achieving companies’ objectives. This computer application can be used as a learning tool for identifying potential problems that a construction company faces and the most optimum corrective action.
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Decision Support System (DSS) has played a significant role in construction project management. This has been proven that a lot of DSS systems have been implemented throughout the whole construction project life cycle. However, most research only concentrated in model development and left few fundamental aspects in Information System development. As a result, the output of researches are complicated to be adopted by lay person particularly those whom come from a non-technical background. Hence, a DSS should hide the abstraction and complexity of DSS models by providing a more useful system which incorporated user oriented system. To demonstrate a desirable architecture of DSS particularly in public sector planning, we aim to propose a generic DSS framework for consultant selection. It will focus on the engagement of engineering consultant for irrigation and drainage infrastructure. The DSS framework comprise from operational decision to strategic decision level. The expected result of the research will provide a robust framework of DSS for consultant selection. In addition, the paper also discussed other issues that related to the existing DSS framework by integrating enabling technologies from computing. This paper is based on the preliminary case study conducted via literature review and archival documents at Department of Irrigation and Drainage (DID) Malaysia. The paper will directly affect to the enhancement of consultant pre-qualification assessment and selection tools. By the introduction of DSS in this area, the selection process will be more efficient in time, intuitively aided qualitative judgment, and transparent decision through aggregation of decision among stakeholders.
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In this paper we discuss our current efforts to develop and implement an exploratory, discovery mode assessment item into the total learning and assessment profile for a target group of about 100 second level engineering mathematics students. The assessment item under development is composed of 2 parts, namely, a set of "pre-lab" homework problems (which focus on relevant prior mathematical knowledge, concepts and skills), and complementary computing laboratory exercises which are undertaken within a fixed (1 hour) time frame. In particular, the computing exercises exploit the algebraic manipulation and visualisation capabilities of the symbolic algebra package MAPLE, with the aim of promoting understanding of certain mathematical concepts and skills via visual and intuitive reasoning, rather than a formal or rigorous approach. The assessment task we are developing is aimed at providing students with a significant learning experience, in addition to providing feedback on their individual knowledge and skills. To this end, a noteworthy feature of the scheme is that marks awarded for the laboratory work are primarily based on the extent to which reflective, critical thinking is demonstrated, rather than the amount of CBE-style tasks completed by the student within the allowed time. With regard to student learning outcomes, a novel and potentially critical feature of our scheme is that the assessment task is designed to be intimately linked to the overall course content, in that it aims to introduce important concepts and skills (via individual student exploration) which will be revisited somewhat later in the pedagogically more restrictive formal lecture component of the course (typically a large group plenary format). Furthermore, the time delay involved, or "incubation period", is also a deliberate design feature: it is intended to allow students the opportunity to undergo potentially important internal re-adjustments in their understanding, before being exposed to lectures on related course content which are invariably delivered in a more condensed, formal and mathematically rigorous manner. In our presentation, we will discuss in more detail our motivation and rationale for trailing such a scheme for the targeted student group. Some of the advantages and disadvantages of our approach (as we perceived them at the initial stages) will also be enumerated. In a companion paper, the theoretical framework for our approach will be more fully elaborated, and measures of student learning outcomes (as obtained from eg. student provided feedback) will be discussed.
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In this study, poly (e-caprolactone) [PCL] and its collagen composite blend (PCL=Col) were fabricated to scaffolds using electrospinning method. Incorporated collagen was present on the surface of the fibers, and it modulated the attachment and proliferation of pig bone marrow mesenchymal cells (pBMMCs). Osteogenic differentiation markers were more pronounced when these cells were cultured on PCL=Col fibrous meshes, as determined by immunohistochemistry for collagen type I, osteopontin, and osteocalcin. Matrix mineralization was observed only on osteogenically induced PCL=Col constructs. Long bone analogs were created by wrapping osteogenic cell sheets around the PCL=Col meshes to form hollow cylindrical cell-scaffold constructs. Culturing these constructs under dynamic conditions enhanced bone-like tissue formation and mechanical strength.We conclude that electrospun PCL=Col mesh is a promising material for bone engineering applications. Its combination with osteogenic cell sheets offers a novel and promising strategy for engineering of tubular bone analogs.
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Actions Towards Sustainable Outcomes Environmental Issues/Principal Impacts The increasing urbanisation of cities brings with it several detrimental consequences, such as: • Significant energy use for heating and cooling many more buildings has led to urban heat islands and increased greenhouse gas emissions. • Increased amount of hard surfaces, which not only contributes to higher temperatures in cities, but also to increased stormwater runoff. • Degraded air quality and noise. • Health and general well-being of people is frequently compromised, by inadequate indoor air quality. • Reduced urban biodiversity. Basic Strategies In many design situations, boundaries and constraints limit the application of cutting EDGe actions. In these circumstances, designers should at least consider the following: • Living walls are an emerging technology, and many Australian examples function more as internal feature walls. However,as understanding of the benefits and construction of living walls develops this technology could be part of an exterior facade that enhances a building’s thermal performance. • Living walls should be designed to function with an irrigation system using non-potable water. Cutting EDGe Strategies • Living walls can be part of a design strategy that effectively improves the thermal performance of a building, thereby contributing to lower energy use and greenhouse gas emissions. • Including living walls in the initial stages of design would provide greater flexibility to the design, especially of the facade, structural supports, mechanical ventilation and watering systems, thus lowering costs. • Designing a building with an early understanding of living walls can greatly reduce maintenance costs. • Including plant species and planting media that would be able to remove air impurities could contribute to improved indoor air quality, workplace productivity and well-being. Synergies and References • Living walls are a key research topic at the Centre for Subtropical Design, Queensland University of Technology: http://www.subtropicaldesign.bee.qut.edu.au • BEDP Environment Design Guide: DES 53: Roof and Facade Gardens • BEDP Environment Design Guide: GEN 4: Positive Development – Designing for Net Positive Impacts (see green scaffolding and green space frame walls). • Green Roofs Australia: www.greenroofs.wordpress.com • Green Roofs for Healthy Cities USA: www.greenroofs.org