Engineering Commons^™

Material And Energy Flow Analysis Of The Irish Construction Sector, Rachel Woodward

Theses

A national flow model for concrete was developed using the framework of material and energy flow analysis. Using this framework, the Irish concrete material and energy cycles for the year 2007 were constructed by firstly analysing the material life cycle of concrete which consists of the three phases of production (including extraction of raw materials and manufacture of cement), usage into stock (ready-mix and other concrete products), and waste management. In this year, approximately 35Mt of raw materials were extracted to produce both 5Mt of cement and 33Mt of concrete, with 4.5Mt of cement going into the production of concrete. …

Behaviour Of Unbonded Post- Tensioned Segmental Box Girders With Dry Joints, Michael Matson

Theses

The primary objective of this thesis is to examine the capacity of shear keys used in dry jointed precast post-tensioned segmental box girder bridge construction. The use of dry joints, in lieu of the more traditional glued joints, is becoming more popular in climatically suitable countries. The time and cost savings achieved using this construction form arc significant, due to the economies of scale involved.

The shear capacity of dry jointed keys is calculated using a number of available formulae. However, in previously published papers, significant differences have been noted in the results obtained from these formulae, deeming further investigation …

Miniature Embedded Module For Prognostic Health Monitoring (Phm) Of Electronic Systems, Liam Moore

Theses

Sensing systems for reliability prognostics are used extensively in life- and mission- critical electronics systems. They allow monitoring of reliability stresses in real time and scheduling of preventative maintenance before system failure. However, reliability prognostics systems are, in general, large and expensive and cannot be used in lower cost, small sized or portable products.

This thesis presents a sensing module for reliability prognostics which is only 1cm in volume and uses only commercial off-the-shelf components. In its 1cm package, the module combines all the necessary elements to act as an embedded prognostic sensor system for multi axial strain, vibration, humidity …

The Optimum Energy Crop In Ireland For Biofuel, Eoin Deasy

Theses

The motivation for this research stems from the potential of biofuels to assist Ireland in meeting obligations outlined in the 'Renewable Energy Source Directive' (2009/28/EC) and to reduce dependency on fossil fuels. The purpose of this work is to establish the merits of biofuel production Ireland ,with a keen focus on the technical, economic and environmental aspects of each. The three biofuel options investigated are biodiesel, bioethanol and biomethane. Eight crop varieties were investigated, these include; wheat, oats, barley, OSR, maize silage, sugar beet, grass silage and potatoes. The approach taken within this thesis was to perform a life cycle …

Rubble-Mound Structure Design In The Coastal Environment, Jack Murphy

Theses

The main aims of this thesis were to investigate the main aspects of the design and implementation of rubble-mound structures as a form of shoreline stabilisation and coastal defence. An emphasis has been placed on the Irish context of how these structures have been implemented in the past. The intention was that this work would improve the understanding of the use of these structures for future projects both in Ireland and internationally.

This work required a literature review which investigated the general aspects of rubble-mound structures, the coastal environment, and the theory of designing the structures’ layout, cross-section and impact …

Protection Of Embedded Systems For Applications Involving High Loading Rate Mechanical Forces, Amjad Alsakarneh

Theses

This thesis describes the development of a methodology to optimise the dimensions and mechanical properties of force-absorbing layers surrounding miniaturised embedded electronic modules subject to high mechanical compressive/impact forces and vibration. While much has been published on the mechanical protection of electronic systems in larger scale applications, where traditional mechanical shock absorbers and springs can be used to protect the electronics, little has been published on the mechanical protection of miniature electronic modules embedded in smart structures and materials where traditional methods of mechanical protection are not feasible. The generalised system concept used in this thesis is of module encapsulation …

Geotechnical, Environmental And Regulatory Aspects Of Brownfield Development, Martin Casey

Theses

Brownfield sites are a common feature of the urban landscape, have significant development potential and when remediated are the catalysts for urban regeneration. However, site specific information regarding geotechnical and environmental aspects of the site, including regulatory issues are needed in terms of bringing the land back into beneficial use. This research project discusses current Irish practice and regulation in respect of brownfield development. A comparison is made between Ireland, the United Kingdom, and the European Union in this regard. A review of all available literature indicates a number of shortcomings in respect of the geotechnical, environmental and regulatory aspects …

Semi-Automatic Management Of Knowledge Bases Using Formal Ontologies, Andreas Textor

Theses

This thesis presents an approach that deals with the ever-growing amount of data in knowledge bases, especially concerning knowledge interoperability and formal representation of domain knowledge. There arc multiple issues that must be addressed with current systems. A multitude of different formats, sources and tools exist in a domain, and it is desirable to develop their use further towards a standardised environment. Such an environment should support both the representation and processing of data from this domain, and the connection to other domains, where necessary. In order to manage large amounts of data, it should be possible to perform whatever …

Creep Behaviour Of Hand Laminated Glass Reinforced Polymer Composites., Brain Quinn

Theses

The creep behaviour of hand laminated, glass fiber reinforced polyester composites were studied at coupon level, due to the use of similar materials in long term load bearing civil and structural engineering applications. Creep predictions were made by fitting the parameters of several viscoelastic models to experimental creep data as well as two accelerated test methods, time temperature superposition (TTS) and frequency time transformations (FTT). TTS experiments were carried out in a dynamic mechanical analyzer (DMA) in three point bending mode for three types of material systems. Creep compliance master curves representing the linear viscoelastic creep response at reference temperatures …

Calorific Values Of Building Materials And Their Effect On The Structural Environment, Graham Doyle

Theses

As materials are seen to be a distinct source of fire and to avoid the destructive effects of fire to people and the environment, there is certainly a need for an assessment of building materials, internal finishes and contents to be conducted in a fire engineering context. This report examines the effect of these materials on the structural environment with a view of ultimately determining compartmental fire loads.

Research has shown that there is a significant lack of information available in regards to the calorific values of materials, and in particular building materials. In addition, material calorific values and generic …

Composition-Structure-Property Relationships For Experimental Composite Nerve Guidance Conduits, Xiaofang Zhang

Theses

Many Nerve Guidance Conduits (NGCs) have been approved by the Food and Drug Administration (FDA) as an alternative to nerve autografting for guiding peripheral nerve regeneration. However these materials offer little therapeutic potential for favourable axon growth environment, and difficulty in balancing the mechanical properties and the degradation rate of the implanted material is also a contemporary challenge. This project involved the design of experimental composite NGCs comprising glass particles and Pluronic FI27 in the copolymer (poly(lactic-co-glycolic acid)) and examined the composition-structure-property relationships for such materials. Three glasses (0.5Si-(x) Na-0.2Ca-0.13Zn-(0.17-x) Ce) (0.0.04 > x > 0.14) were produced. Glasses were characterised using …

Scenario Generation And Climate Change Modelling Of Nitrous Oxide Emissions From Grasslands In Ireland, Mark Cochrane

Theses

Described as a two-year study in relation to nitrous oxide emissions from agricultural grassland in the Republic of Ireland under a set or climate and environmental policy scenarios. Nitrous oxide is a greenhouse gas, with a global warning potential approximately three hundred times that or carbon dioxide. lt is required under the Kyoto Protocol that national inventories or all greenhouse gas emissions are established. The Intergovernmental Panel on Climate Change (IPCC) Tier approach is designed to establish current inventories of greenhouse gas emissions; however a scenario approach is also employed in order to estimate emissions in future years. Scenario sets …

Design Of A Centralised Anaerobic Digestion Plant In Ireland., Diarmuid O'Meara

Theses

Climate change is brought about by greenhouse gases emitted to the earth’s atmosphere by fossil fuels. Renewable energy sources are seen as an alternative to fossil fuels. Examples of renewable energy sources are biofuels which are a method of reducing the emission of greenhouse gases. One form of biofuels is biogas that is produced during the anaerobic digestion process. In this thesis pig slurry is used to produce biogas.

In this project, the optimum design process for a centralised anaerobic digestion plant was established in the literature review, The optimum process for anaerobic digestion plant design in Ireland was investigated. …

Semi-Rigid Steelwork Connections, Conor Murphy

Theses

This thesis sets out to assess the stiffiiess of typical fin plate steelwork connections. The classification of joints as pinned, semi-rigid or fixed is described and the different models of moment-rotation relationship are explained. Eurocode treatment of steelwork connections is assessed with particular emphasis on joint stiffness. Procedures for the design of fin plate connections are set out and an example presented and a spreadsheet developed. Tests on a number of fin plate connections were carried out in the Heavy Structures Laboratory, to determine the moment rotation characteristics. The finite element software LUSAS was used to analyse the fin plate …

A Finite Element Study Of Precast Prestressed Concrete Circular Tanks Subject To Elevated Temperatures, Michael Minehane

Theses

The current study investigates the influence of heated water storage, upward of 95°C, on precast prestressed concrete circular tanks. Modem design standards for liquid- retaining concrete structures stipulate that thermal effects are to be considered for the serviceability limit state. They are also to be considered for the ultimate limit state when deemed significant. The standards, however, do not provide guidance for the analysis of such effects. Research in this area is also limited and exclusively concerned with ambient thermal conditions, with a maximum temperature of 30 °C in any instance.

A finite element study incorporating thermo-mechanical coupling investigates the …

Feasibility Report On Use Of Anchored Gravity Bases For Offshore Wind Turbines, Anthony Hayes

Theses

In recent years, the demand for renewable energy in Europe has been rising substantially, as a result of statutory demands put in place by the European Union. It is expected that a relatively large proportion of future renewable electricity will be supplied by offshore wind farms. The offshore wind industry is currently attempting to design and evaluate cost effective foundation systems suitable for water depths greater than 30m. There is also a drive to reduce foundation costs for offshore wind turbines at present. This project is a preliminary feasibility report on an anchored gravity base foundation concept for deployment at …

Design Of A Smart System For Monitoring Concrete Curing And Structural Health, William Quinn

Theses

Structural Health Monitoring (SHM) is a rapidly growing sector of the construction industry. Automated monitoring methods arc mainly limited to global monitoring and the application of local monitoring methods has not gained widespread application due to the fact that currently technology requires that the systems are wired to data acquisition devices. This thesis presents a fully embeddable wireless sensor node for the local monitoring of structural concrete. It presents the first reported wireless embedded system implementation of the electromechanical impedance method using both resonant and antiresonant sensors for this purpose.

The first section of this thesis examines the feasibility of …

Ultra Wideband Pulse Shaping, Pawel Rulikowski

Theses

Methods for shaping of sophisticated, transient, ultra wideband (UWB) waveforms and pulses are presented. The methods include novel circuits based on step recovery diodes (SRDs) and quasi-transversal filter concepts but the majority of the work focuses on UWB pulse shaping using completely passive nonuniform transmission lines (NUTLs). It is shown, for the first time, that NUTLs can be used to generate highly sophisticated arbitrary UWB pulse shapes, including modified Hermite polynomial (MHP) and approximate spheroidal wave function (APSWF) pulses which are not known to have been previously generated in practice, and a generalized methodology, verified by experiments, for design of …

Power Cable Fault Finding Using Pseudo Random Binary Sequences, Holger Geisler

Theses

The work that is presented in this thesis documents the results obtained from the pseudo random binary sequence (PRBS) cable testing method which utilises a pseudo noise (pN) sequence as a test stimulus to localise faults on a transmission line. The work targets the proof of concept of the PRBS method in a Coaxial cable as well as its eventual evaluation for fault testing accuracy and performance on a real-world underground steel wired armour (SWA) cable. Further, a novel hardware implementation of the method utilising a Field Programmable Gate Array (FPGA) is presented. The theory of the PRBS test method …