External thermal insulation composite system (ETICS) is a widespread method appearance of the facades of existing and new civil and industrial buildings. With its frequent application becomes engaged his durability issues and possible rehabilitation and more topical. Influences affecting durability ETICS is still under investigation, as well as systematic and practical way to usable redevelopment. The main theme of this work is to summarize knowledge in ETICS issue, particularly from the viewpoint adhesive and leveling materials based on Portland cement and final finishes. The theoretical part is discussed ETICS composition, the composition of its components, technical requirements and factors affecting durability. The experimental part focuses on the redevelopment of ETICS and verification using colloidal silica for modification of construction materials, which are part of the ETICS.

Vehicle dynamic simulations form a significant part of the design and development process of vehicles. These simulations are used to study and improve the vehicle’s durability, ride comfort and handling capabilities. All forces acting on the vehicle are either generated in the tyre-road interface or are due to aerodynamic effects, where at low speeds the latter one can be ignored. The accuracy of the tyre model describing the forces on the tyre-road interface is thus of exceptional importance. It ensures that the simulation model is an accurate representation of the actual vehicle. Various approaches are adopted when developing mathematical tyre models. Many of these models are developed to study the handling capabilities of passenger cars over a smooth road. Passenger car tyres are the focal point as larger tyres introduce some difficulties due to their size and load rating. Off-road truck tyres also differ in their construction which will influence force and moment generation of the tyre. Research efforts are increasing to meet the need of tyre models that can describe the behaviour of the tyre over uneven terrain with sufficient accuracy. This thesis addresses the question of whether existing mathematical tyre models can accurately describe the forces and moments generated by a large off-road tyre while driving over rough terrain. The complexity of different mathematical tyre models varies greatly, as does the parameterisation efforts required to obtain the model parameters. The parameterization of most tyre models relies on some experimental test data that is used to extract the necessary information to fit model parameters. The selection of a suitable tyre model for a simulation is often dependent on the availability of such experimental data and the effort to identify the required parameters. In this study the parameterisation process for four different tyre models, are discussed in detail to highlight the difficulties in acquiring the test data and the effort to parameterize the model. The models considered are the One Point Contact, 3D Equivalent Volume contact, 3D Enveloping Contact and FTire model. Experimental measurements are conducted on a 16.00R20 Michelin XZL tyre. Laboratory tests, as well as field tests, over discrete obstacles and uneven hard surfaces are used for parameterisation and validation purposes. Simulation results are compared to experimental test data to determine whether the models could be used to describe the tyre road interactions with sufficient accuracy. Recommendations are made for tyre model selection and model accuracy for simulations over rough off-road surfaces. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Mechanical and Aeronautical Engineering / unrestricted

Epoxy-coated rebar (ECR) has been used in approximately 300 Florida bridges, in an attempt to control corrosion of the substructure in the splash-evaporation zone. Early severe ECR corrosion was observed in the substructure of several Florida ECR bridges (Group 1) where the substructure was built with permeable concrete of high apparent chloride diffusivity DApp. Other ECR bridges built during the same period and having similar DApp were projected to show corrosion damage starting on the following decade. Examination of several of those bridges (Group 2) confirmed that projection. Other recently examined Florida ECR bridges (Groups 3 and 4) were built with very low to moderate permeability concrete having correspondingly low to moderate DApp values at normally sound concrete locations. Those bridges were projected not to show early corrosion at normal locations and that projection has also been confirmed. However, some incidence of thin structural cracks exists affecting a small fraction of the substructure. Chloride transport there is much faster than through the matrix in otherwise low permeability concrete and work has confirmed that early corrosion can develop there. A predictive ECR corrosion model was applied that replicated most of the damage function features observed in the field. The model divides the substructure in separate elements with individual chloride exposure, concrete permeability, concrete rebar cover, and extent of ECR coating imperfections. Additionally, a model for projecting impact of preexisting cracking on corrosion damage was developed. The projections indicate that relatively isolated cracking should only create topical concrete damage with reduced maintenance requirements. However, model projections indicated that even though assuming that the incidence of damage is limited to a small region around the crack, if the crack orientation with respect to the rebar were adverse and chloride transport were greatly enhanced (as it could be expected in relatively wide cracks), corrosion damage from localized concrete deficiencies could significantly increase maintenance costs. Electrochemical Impedance Spectroscopy (EIS) measurements of ECR in extracted cores showed good potential for non destructive characterization of the extent of coating damage. A possible method accounting for frequency dispersion effects in the high frequency response (of importance to assess extent of defects) was introduced.

In order for composites to become an accepted material for infrastructure application, life prediction and durability must be understood. The majority of studies have examined the strength and fatigue response of composites under hot and/or moist conditions. Various researchers have also studied life prediction methods for composite materials under fatigue, primarily for high performance applications. Little work has been done to study durability under combined service conditions for composites used in civil infrastructure applications. This thesis focuses on the development of a life prediction model for use with fiber reinforced polymer composites in bridge service environments. The Tom's Creek Bridge of Blacksburg, VA is used as a guiding case study. First, the tensile properties of the composite were studied as a function of temperature and moisture. Damage accumulation was studied as a function of cyclic loading and temperature cycles. The enviro-mechanical conditions, including moisture, temperature and fatigue loading, were then used in a computer simulation to predict the life of a vinyl ester/glass composite under an approximate bridge service environment. Finally, a laboratory simulation was conducted that approximates the temperature and humidity that is seen at the Tom's Creek Bridge, but in an accelerated time frame. A multi-stress fatigue pattern, mimicking cars and trucks passing over the bridge, was used. One year of conditions was accelerated to approximately six hours and thirty-three minutes using a servo-hydraulic test frame and environmental chamber. The final results showed that life prediction methodology conservatively predicted the lifetime of a vinyl ester/glass composite under the enviro-mechanical conditions. The damage of the composite was predominately driven by cyclic loading. The environmental conditions of moisture and temperature had only a small affect on the lifetime of the composite. This lack of environmental sensitivity is largely due to the durability of the resin system. / Master of Science

>Magister Scientiae - MSc / Polymer electrolyte membrane fuel cells (PEMFC) are in the forefront of energy production and have drawn a great deal of attention in both fundamental and application in recent years. It is a promising energy system used in commercialized electric vehicles presenting with the following advantages: low-temperature operation, high power density (40%–60%), nearly zero pollutants compared to conventional internal combustion gasoline vehicles, simple structure, and so on. There are, however, two major obstacles which obstruct PMFCs pathway to commercialization— durability and cost. Recent advances in PEMFC systems showed the most common fuel cell catalysts to be Platinum (Pt) (or platinum alloys) supported by high surface carbon in both the cathode and anode. However, carbon is very susceptible to corrosion and results in lower durability of Pt supported catalysts.

In this thesis the corrosion resistance of two types of steel materials were evaluated, Corten A as a representative of WS (weathering steel) and the corrosion resistance of anti-corrosion protection formed by the zinc coating. The different kinetics of corrosive processes was found during the NSS test. WS steel exposed to 400 hours of NSS laboratory test showed growth of the corrosion rate, however, after this period of time there has been a significant decline in this rate. Conversely, when using Zn as anodic protection, the corrosion losses decrease linear up to 300 hours of exposure, but after this time there was a relatively significant linear increase in corrosion rate. During measurements on existing VHV pylons they were measured corrosion decreases of steel and Zn anti-corrosion protection. Normal corrosion rate for weathering steel with 10 m.a-1 and for Zn corrosion loss 1.8 m.a-1 were found. Technical and economic assessment were evaluated using variant of new poles with Zn surface layer and revitalization of existing pylons from WS steel. With regard to all aspects obtained from laboratory tests and economic assessments, friendlier version of revitalization of existing VHV pylons from WS steel using a sufficient corrosion resistance of these steels were found out.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21365号 / 工博第4524号 / 新制||工||1705(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 西山 峰広, 教授 竹脇 出, 教授 河野 広隆 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

This thesis aims to contribute to the growing body of warm mix asphalt (WMA) research by evaluating the differences in behavioral properties of three WMA mixtures, representing the three warm mix technology (WMT) categories (foaming, chemical additives, and organic waxes), relative to a control hot mix asphalt (HMA) in a specific set of conditions which is not well documented in literature. These conditions are: plant produced mixtures with all virgin aggregates and binder (i.e. no recycled materials) and no additives other than the warm mix technology. These mixtures were evaluated at low, intermediate, and high testing temperatures before and after a set of conditioning protocols (CPs), which utilized varying levels of isolated and combined oxidative, moisture, and freeze-thaw damage. A key feature of this thesis is that damage induced by these CPs has been benchmarked relative to measured field aging effects through studies which evaluated the three WMA mixtures and one HMA mixture used to obtain the results presented here, along with additional mixtures not considered in this thesis.

This dissertation undertakes to cast a new and discerning eye on the continuing enigma of Canadian federal innovation policy. Towards that end the dissertation employs the Developmental Network State (DNS) framework and pursues the question of whether the DNS can be used to explain why Canada - and specifically federal innovation policy since 2000 - has seemingly been unable to increase national Research and Development investments and positively impact Canada’s rate of innovation. Theoretically the dissertation argues that the DNS framework can be used to mend the gap between National Innovation Systems literature with its proclivity for an undertheorization of the state and historical institutionalism, which while robustly conceptualizing the state, has been less engaged with the innovation problématique. While admittedly including some modest conceptual sharpening of the framework, the argument draws on four key pillars of the DNS: policy durability over time; targeted resourcing that can enable innovation; thickening of triadic networks among business, academe and government and incentives for capitalization. The research methodology encompasses both qualitative and quantitative (particularly in the sense of economic) techniques and includes 54 in-depth interviews conducted with innovation leaders across the nation. With respect to the evidence assembled around the health of the Canadian innovation system, OECD indicators over the period of the 2000s generally show deteriorating trends, although investment in Higher Education R&D (HERD) is very much the stalwart exception. As for the four lines of inquiry investigated regarding federal policy, the issue of policy durability in large part reveals an increasing number of priorities overlaid at times with exceedingly ambitious objectives and the ongoing challenge of fashioning a more enduring federal strategy. As for targeted resourcing, while federal investments have been both sustained and substantive and while there has been particular attention to macroeconomic stability and research infrastructure, there has been a continuing pattern of oscillation between a focus on research and one on commercialization. With respect to triadic thickening of networks, the evidence continues to reveal the relatively shallow nature of collaboration - this despite robust funding, institutional mechanisms for networking and an ongoing priority on this issue by government. Here again however business financing of HERD stands out as the exception. In contrast, on incentives for capitalization there has been significant progress, although access to late-stage capital remains a challenge. Additionally, the study undertakes an examination of two sectors - Artificial Intelligence (AI) and pharmaceutical manufacturing, employing a “quasi-experimental” technique that examines impacts of policy initiatives over a period that dates back to 1987. In the case of AI, the enabling conditions of DNS do coalesce to form a robust innovation ecosystem. In the case of pharma, policy efforts have not been so sustained or holistic and innovation indicators duly tell this tale of deteriorating trends. In sum, what emerges is that federal innovation policy in the Canadian context has developed in rather truncated form - and it has tracked within the confines of more historically adept and enduring strategies such as upstream Research and Development and fiscal policy. Indeed, the pillars of the DNS framework serve to illuminate the dissonance between policy intent and impact, highlighting the unique nature of federal innovation policies as they have endeavoured to establish the agendas, funding, networks and capital that can provide a formula for advancing Canada on this front. This case study also suggests that the DNS itself may need honing - specifically that policy durability is not only a sufficient condition for innovation but in fact an anchoring one enabling other dimensions to follow suit.

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