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Client's control of constructionBekr, Ghanim Abdul Rehman January 1990 (has links)
No description available.
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Cost models for constructionAl-Jibouri, S. H. January 1985 (has links)
No description available.
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Numerical modelling of tunnel installation and compensation groutingWisser, Claus January 2002 (has links)
No description available.
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Evaluating the Impact of Lean on Employee Ergonomics, Safety, and Job Satisfaction in ManufacturingMorse, Amanda 23 January 2014 (has links)
The goal of this study was to explore the proposed relationship between employee satisfaction, ergonomics, and safety while implementing a Kaizen event. In order to address this goal, two Kaizen events (K1 and K2) were conducted in a heavy equipment manufacturing plant. Before and after both events, levels of employee satisfaction were documented for Kaizen and Non-Kaizen (NK) participants using the Job Diagnostic Survey (JDS). The objective of the first event (K1) was to improve the efficiency of the task of torqueing the rear axle bolts in Station #1- skid assembly. The K1 methodology followed a traditional Kaizen structure, enhanced with ergonomic and safety evaluation tools, Rapid Entire Body Assessment (REBA) and Job Hazard Analysis (JHA) respectively. During the event (K1), problem areas caused by the current skid were identified, analyzed, and a new skid was developed and implemented via a prototype. After testing the prototype all skids were replaced for full implementation. Ergonomic and safety was again evaluated. By using this approach to redesign the process, it was possible to improve productivity (83%), while reducing employee safety (5 JHA hazards to 1 hazard) and ergonomics (Employee #1 REBA score 13 to 11). The objective of the second kaizen event (K2) was to improve the efficiency of the manufacturing process for the welding subassembly station. The K2 methodology followed a traditional Kaizen structure, where the team identified the key problems for the welding subassembly station, analyzed the concerns for the material arrival, developed a solution for more consistent material delivery, and implemented a solution. By using Kaizen as a tool to address scheduling and material movement it was possible to improve the manufacturing process efficiency (36%). The JDS evaluation revealed mixed results for the impact of a Kaizen event on job satisfaction- some employees job satisfaction levels increased when others decreased. The findings also show that some characteristics (Feedback from Agents (p=0.036), Experienced Meaningfulness of the Work (p=0.036), Growth Satisfaction (p=0.027), Satisfaction with Compensation (p=0.034), and Motivating Potential Score (p=0.025)) were significantly different across participants groups (e.g. K1, K2 and NK). The events helped to encourage communication and involvement making the new processes more efficient and less frustrating for employees. Findings from this research contribute to a better understanding of the impact of lean on employees ergonomics, safety, and job satisfaction.
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VOLWASSENHEID VAN BOUREKENKUNDIGE KOMMUNIKASIE IN DIE KONSTRUKSIEBEDRYFBerry, Frank Herman 27 May 2013 (has links)
Although the quantity surveyors had laid their claim to the building industry for more
than a century, poor scientific knowledge analyses with reference to the professional
communication capabilities and communication instruments in the construction
industry still exists.
The aim of this thesis is to measure the determinants of a communication maturity
model in respect of the communication capabilities of the profession. The proposed
most important determinants used were brought to light through research undertaken
by the University of the Free State in collaboration with the Wirtschafts University in
Vienna, Austria in 2005/6.
The results of the survey indicate that respondents were positive with regard to
professional communication in general. This can influence the construction industry
with continuous advantages for the property development environment.
The survey results indicate that the determinant contractual communication of the
quantity surveyor is experienced the most positive. The determinant leadership
communication of the quantity surveyor is experienced the least positive.
A model of the most important determinants for effective communication was used to
measure the maturity of the professionâs communication capabilities in the
construction industry.
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PROJECT MANAGEMENT IN THE BUILT ENVIRONMENT: THE NEED FOR INDUSTRY SPECIFIC KNOWLEDGEBurger, Michelle 23 July 2013 (has links)
The use of project management has expanded and is used in many industries. The generic component of project management across all industries without the necessary technical knowledge has been debated. This study investigates the knowledge base of construction project management and the need for industry specific knowledge.
The study includes a literature and also empirical research section. The empirical study made use of interviews, a case study and questionnaires. A construction project management knowledge model was developed based on the research and research findings. The research findings suggest that a project manager in the built environment requires various types of knowledge â project management knowledge, industry specific knowledge and knowledge gained through experience. The project management knowledge includes the 13 areas from the construction extension to the PMBOK guide, the industry specific knowledge is divided into four main areas that are knowledge of construction science, knowledge of construction processes, knowledge of design processes and knowledge of financial cost factors and the knowledge through experience is gained through time spent working in the industry.
The construction project management knowledge model aims to contribute to improving the project management environment, aiding in awareness of the various knowledge areas and subareas that are important and the NQF level that is suggested. This could contribute to sufficient education by creating awareness of the level of education a project manager in the built environment requires. Organisations could use the model as reference to determine which areas their project managers could improve on in order to develop and increase project management maturity in the organisation. The project management construction model also offers tertiary institutions a framework for syllabus planning of constructions project management courses. Further research is welcomed and may include improving the model, or using the model as foundation to develop a measuring instrument to determine the knowledge of a construction project manager.
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Experimental and analytical study of the shear transfer in composite shallow cellular floor beamsHuo, Bingyu January 2012 (has links)
This research investigated the longitudinal shear transfer mechanism in composite shallow cellular floor beams. The shear transfer mechanism is different with the headed shear studs used in composite construction. The shear resisting properties and behaviour of the shear transfer mechanism has not been studied previously. Experimental and analytical studies were carried out with the aims of improving and optimizing the design details, and advancing the method of shear connection in shallow floor beam construction. The composite shallow cellular floor beam investigated in this research is a new type of beam fabricated by welding two highly asymmetric cellular tees along the web. The shear connections of this type of composite beam are formed by the web openings, which transfer longitudinal shear force. Four types of these shear connections were studied: concrete-infill-only, tie-bar, ducting and web-welded-stud shear connections. In total, 24 push-out tests were performed in two test series to investigate the load-slip behaviour and shear resistance of the shear connections under direct shear force. The failure mechanisms of the two forms of shear connections were extensively studied, which lead to the development of a design method for the composite action. The concrete infill element passing through the web opening is subject to a complex three-dimensional stress state, and it is difficult to analyse it using the mathematical model rather than empirical formula. Finite Element Analysis of the concrete-infill-only shear connection was performed with a parametric study to further verify the design method that has been developed. Two flexural tests were carried out on a full-scale composite shallow cellular floor beam with a solid slab. The shear connections investigated in the flexural tests were: concrete-infill-only and tie-bar shear connections passed through the web. The behaviour and performance of the shear connections in the flexural tests were compared with those in the push-out tests. The degree of shear connection of the two flexural tests was determined in the back analysis using plastic theory with measured material properties. Based on the findings of the push-out tests and flexural tests, two design methods of deflection check and moment resistance were developed for composite shallow cellular floor beams at the serviceability limit state and the ultimate limit state respectively. The deflection check design method is based on the uncracked section properties of the composite beam. The moment resistance design method developed in this thesis is compatible with the design methods of BS5950 and Eurocode 4 (EC4).
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Design of interlocking bricks for enhanced wall construction, flexibility, alignment accuracy and load bearingKintingu, Simion Hosea January 2009 (has links)
The worldwide housing shortage has stimulated a search for appropriate, easy, fast and cost-effective new ways of wall construction. Among many technologies found to have promise is mortarless technology using dry-stack interlocking bricks/blocks. This thesis is about such mortarless walling technology and in particular: how to improve wall-construction flexibility, the effects of brick irregularities on wall alignment accuracy and wall behaviour (stiffness, strength) when subject to lateral forces. The flexibility of mortarless technology (MT) has been enhanced by the development of new bricks (centre-half bat and tee brick): the introduction of closer bricks led to the formation of two new bonds (patterns) namely Shokse and Lijuja bonds. It is now possible to construct more than half-brick-thick walls, to attach more than half-brickwide piers (buttresses) onto walls, and, using special bricks, to construct polygonal and curved walls using interlocking bricks. Three methods (theoretical modeling, physical experiments and computer simulation) were used to analyze the effects of brick imperfections on wall alignment accuracy. Theoretical analysis confirmed that brick moulders should concentrate on achieving parallel top and bottom faces rather than achieving true square-ness. Physical column assembly compared three brick-laying strategies namely: “random”, “reversing” and “replace”. The columns assembled using the “reversing” and “replace” strategies realized alignment improvement factors of 1.6 and 2.9 respectively over “random” strategy. The research also revealed that grooving, to prevent bricks making contact near their centre lines, improved column alignment by factor 2.13 and stiffness by factor 2.0, thus allowing construction of longer and higher walls without strengthening measures. In order to attain alignment accuracy in accordance with BS 5628-3:2005 in a dry-stack mortarless wall, this research recommends using full bricks with top and bottom surface irregularities not exceeding ±0.5mm for un-grooved bricks, and up-to ±0.9mm for grooved bricks. Further analysis was undertaken with respect to resource-use implications (cement, water, soil) of employing MT. Using MT will save 50% of wall construction cost and 50% cement consumption, which ultimately will reduce 40% of carbon emissions.
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A modelling study of segmentation of naturally ventilated tall office buildings in a hot and humid climateLiu, Pei-Chun January 2012 (has links)
The prevailing paradigm in indoor environment control of office buildings often excludes natural ventilation, due to the fact that its dynamic nature may not be compatible with the close control of mechanical conditioning systems. The challenges will be greater in terms of the potential high magnitudes of wind and buoyancy forces at high levels of tall buildings. This research is concerned with the prospect of tall office buildings that are purely naturally ventilated. It is proposed that “segmentation” might offer the least risky approach for natural ventilation design of non-domestic tall buildings. Accordingly, the generic design procedure are proposed for investigating the influence of segmentation on ventilation air flows: firstly, the single-cell envelope flow model is adopted to evaluate the steady-state bulk flows through openings under a specified design condition; secondly, dynamic thermal modelling with an air flow network module is used, because of the particular importance of the coupling between the airflow and thermal process for evaluating the year-round ventilated cooling potential of targeted spaces. The chosen thermal model utilizes a multi-cell airflow network model (AFN) since the targeted buildings can no longer be described by a single-cell model; thirdly, computational fluid dynamics (CFD) simulation is suggested in the later design stage to cope with insufficient resolution of local airflow distribution in previous modelling stages; finally, the overall performance of comfort ventilation is then interpreted in relation to adaptive thermal comfort theory by the use of Building Bioclimatic Charts, which offers a way of rapidly testing whether or not natural ventilation is likely to produce comfortable conditions. The novelty of this work lies not in the methodology, which uses available modelling tools, but in the evaluation of naturally ventilated tall buildings with reference to segmentation in the climatic context of Taiwan. The effect of segmentation is evaluated by comparing the overall ventilation performance under three different building configurations, namely the isolated, segmented and non-segmented tall buildings. The overall objectives are to determine whether the magnitudes of air flow rates and the resultant flow velocity can achieve the desired comfort ventilation over a range of specified conditions. Potential scenarios where the design goals may not be ensured are identified. The feasibility for naturally ventilated tall office buildings in hot and humid climates is clarified accordingly.
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Enhanced flame retardant polymer nanocompositesElbasuney, Sherif January 2013 (has links)
Fire is a continuous threat to life and property. The total annual UK fire loss is estimated to be 0.25% of its gross domestic product (GDP) (Goddard, 1995). According to fire statistics, more than 12 million fires break out every year in the United States, Europe, Russia, and China killing about 166,000 people and injuring several hundreds of thousands (Morgan and Wilkie, 2007). Polymers which take up 80% of the organic chemical industry, are known for their high flammability with the production of heat, corrosive toxic gases, and smoke (Bent, 2010). Improving the fire retardancy of polymeric materials is a major concern and also a major challenge. Nanotechnology could have a significant impact on polymeric materials through the achievement of polymer nanocomposites (PNs) with enhanced functional properties (Giannelis, 1996, Schartel and Batholmai, 2006). If this can be achieved, there will be an enormous increase in the use of improved flame retardant (FR) PNs in mass transportation, aerospace, and military applications where fire safety will be of utmost importance (Horrocks and Price, 2008). In this research project nanoparticles that could have a synergistic effect with traditional FR systems, or that could have a FR action (nano-fire extinguishers), were formulated and surface modified during continuous hydrothermal synthesis (CHS). The bespoke nanoparticles were developed in a structure that could be easily integrated and effectively dispersed into a polymeric matrix. A solvent blending approach for integrating and dispersing colloidal organic modified nanoparticles into polymeric matrices was developed. The impact of nanoparticles of different morphologies including nanospheres, nanoplates, and nanorods on epoxy mechanical, thermal, and flammability properties was evaluated. A laboratory based technique using a Bunsen, video footage, and image analysis was developed to quantify the nanocomposite's direct flame resistance in a repeatable fashion. A new self extinguishing epoxy nanocomposite was developed which showed an enhanced performance in extreme conditions and with good mechanical properties.
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