Bridges and other coastal structures in Georgia and throughout the Southeast are deteriorating prematurely due to corrosion. Numerous corrosion initiated failures have occurred in precast prestressed concrete (PSC) piles and reinforced concrete (RC) pile caps, leading to the costly repair and replacement of either the entire bridge or the affected members. With the Federal Highway Administration's goal of a 100-year bridge service life and recent legislative action such as the Bridge Life Extension Act, new emphasis has been placed on the development and implementation of new corrosion mitigation techniques. This thesis involves the mechanical testing, and proposed future test program of high-strength stainless steel (HSSS) prestressing strand to be used in prestressed marine bridge piles. The metallurgy for two types of HSSS strand was selected from a previous study of the corrosion resistance, mechanical properties, and feasibility of 6 candidate HSSS drawn wire samples. Duplex stainless steel (DSS) grades 2205 and 2304 were selected for production of 7-wire 1/2" diameter prestressing strand. DSS wire rod was drawn, stranded, and heat-treated using the same production methods and equipment as used for standard of practice, high carbon prestressing strand. The production process was documented to analyze the problems facing this production method and suggest improvement and optimization. After production, the strands were subjected to a series of mechanical tests. Tension testing was performed to provide a stress-strain curve for the strands and related mechanical properties. Wire samples were also taken at varying points in the drawing process to give more information about the work hardening of the stainless steels. Stress relaxation testing was performed on both strand and wire samples to assess the overall losses and to provide comparisons between strand and wire test results as well as drawn wires before and after heat-treatment. An experimental program for future study was designed to assess the HSSS prestressing strand behavior in precast piles. This testing involves assessment of pile driving performance, pile flexural and shear behavior, strand transfer and development length, long-term prestressing force losses, and material durability.

Främsta anledningen till en tilläggsisolering är att det önskas bättre energihushållning i en byggnad. Detta kan göras med olika material och olika tekniker. Inom byggnadsvårdssammanhang förs det en diskussion om de fuktbuffrande materialen är bättre vid tilläggsisolering då de är hygroskopiska än de icke hygroskopiska som är mest frekvent använda i det konventionella byggandet. Denna rapport utvärderar om det finns några dokumenterade fakta som styrker att de hygroskopiska och ekologiska materialen fungerar bättre i byggnadsvårdssammanhang än de icke hygroskopiska. Olika isolermaterial från de två nämnda grupperna jämförs utifrån olika parametrar. / This report evaluates if there are any known facts that support that the hygroscopic and ecologic materials are better in supplement insulation than non hygroscopic. Different kind of insulate materials from these two mentioned groups are compared from without different kind of parameters.

The aim of this study was to determine the quantity of construction waste for several construction materials and to state the probable origins of this waste, depending on case studies in Turkey. There is a lack of documented quantitative data in Turkey on how much material waste the construction industry generates and what amount of such materials remain unused due to this waste. Although some amount of waste is accepted as unavoidable, the probable reasons for it are unclear. Therefore, the study focused on determining waste percentage values for certain materials based on several construction projects and assessing the reasons for this as stated by the professionals who were involved in the construction process of these projects. For practical reasons, it was confined to the material amounts in the bill of quantities, progress payment reports and invoices for four different construction materials / namely, ready-mixed concrete, rebar, brick and floor block, which belonged to eight different projects of two construction companies. Data compiled on these aspects were analyzed statistically via ANOVA and regression analyses. The results showed that waste percentage values displayed differences among materials. Design-related aspects, skill level and attitude of labor, incorrect calculation of material quantities, contractual clauses and material defects were the most effective reasons for waste within the projects analyzed.

<p>Engine development today is driven by cost, performance and government regulations. Customers want cars and trucks to consume less fuel, last longer, pollute less and be safer. Several of the requirements have tribological associations. For example, product longevity can be improved by lowering friction and using more wear-resistant components. In recent decades, the use of new coating application procedures and techniques has produced remarkably advances in relation to cutting tools. The process temperature at which coatings are applied has been lowered to below 200 oC. Thus it is now possible to coat low-alloy temper-sensitive steels, which are widely used in the automotive industry in machine elements such as gears, bearings and cam followers. </p><p>The aim of this work has been to investigate the possibility of using sputtered amorphous carbon coatings to reduce friction and prevent wear in engine components, and specifically in valve train components. Test equipment simulating near-normal running conditions for the valve mechanism has been developed and used to test standard and coated valve components. The mechanism has also been analysed and simulated numerically. The results show a low velocity difference between the injector cam lobe and the roller, except for a short interval at the top dead centre of the rocker arm. In that region the slip increases significantly at higher speeds due to inertial forces. </p><p>A three-dimensional finite element parameter study of the coating thickness, elastic modulus, asperity contact size and wavelength has shown that tensional stresses at the coating surface increase significantly when asperity contacts approach and interact. Testing of different thicknesses in rolling contact, together with finite element stress analysis, showed that a higher tensional stress level through the coating thickness increases the possibility of cracks propagating down to the interlayer and causing delamination of the coating. Tests with a rapid load increase on two carbon coatings show no transition from mild to more severe wear. Instead the contact is dimensioned by the plastic deformation of the underlying substrate.</p>

Recent improvements in warm mix asphalt technologies have spurred an aggressive adoption of these new practices within the asphalt paving industry. Concerns have arisen among federal and state agencies about the effects of this line of products on the performance of asphalt pavements. An investigation of the effects of lowering mixing, aging and compactions temperatures while varying the loose mix aging time was performed. Hamburg Wheel Tracking, Flow Number, Dynamic Modulus and Fracture Energy testing were used to evaluate mechanistic properties of the materials.

The aim of this study was to investigate and compare the availability of construction materials affect children's constructions and play. Observations were made when the children were allowed to play and build with very little and much of the material play-doh dough in preschool. The study is aimed at children aged 3 – 5 years. Interviews were also conducted with educators in departments where the children spent time to give support to this study. The result shows that the children create as many designs of any material amount. At smaller amount of the same material of construction results show that children vary more among different games. / Syftet med det här examensarbetet var att undersöka och jämföra hur tillgången till konstruktionsmaterial påverkar barns konstruktioner och lek i förskolan. Undersökningen riktar sig mot barn i åldrarna 3 – 5 år. Observationer gjordes när barnen fick leka och konstruera med tillgång till mycket och lite av materialet play- doh deg. Även intervjuer gjordes med pedagoger på avdelningarna där barnen vistades för att ge stöd i arbetet. Resultatet visar att barnen skapar lika många konstruktioner oavsett materialmängd. Vid mindre mängd av samma konstruktionsmaterial visar resultatet att barnen skiftar mer mellan olika lekar.

The objective of this study was to investigate the feasibility of using salvaged timber from deconstructed buildings in Turkey. The intention was to show that the re-use of &lsquo / waste&rsquo / materials, while decreasing the cost of construction also preserves the environment from wasteful and extensive use of natural resources. It is hoped that the findings of such a study will encourage professionals to use second hand timber components in Turkey. In order to deal with the waste problem and to save our planet the re-use of construction materials from economic, environmental, social, and historic points of views should be pursued. This research incorporated information about the re-use of timber, including ongoing projects around the world, as reported by the International Council for Research and Innovation in Building Construction (CIB) Task Group on Deconstruction (TG39), a local survey of individuals, organizations, and businesses that are related to the recycling and reuse of building materials. Local deconstruction works, recovery and re-use of timber elements and components were investigated on the basis of information obtained from the demolition contractors in Bentderesi locality in Ankara, a salvaged materials market. iii Moreover the study aimed to observe how used timber components are recovered from a demolition project. By observing the demolition of a building the author was able to determine the problems in recovering timber with the least damage. The findings of the investigation indicated that the architects and the building industry can play an important role to increase recovery rates and conditions of used timber components in construction, considerably. Instead of using nails for timber joints bolted connections should be preferred since they allow demounting and re-use with minimum damage during the deconstruction process. At the same time defects in timber due to extensive and unnecessary nailing can also be avoided. The decision on type of deconstruction, time and cost estimation, worker ability and sensitivity during disassembly influence the success of deconstruction. Tools and machinery used both on the work site and in the UBMs selling area have direct effects on the condition of recovered materials.

The aim of this study was to provide information about the effects of construction materials on thermal comfort in residential buildings using Ecotect 5.0. Three residential buildings, each of different construction in the province of Yozgat, Turkey were used as study material to this end. At the end of this study, the effects of materials on thermal comfort have been explained by graphical and statistical analysis. Pertinent literature reports that the thermal responses of occupants depend to some extent on the outdoor climate in naturally ventilated buildings with operable windows. Furthermore, an adaptation occurs in these buildings regarding the occupants&amp / #8217 / previous thermal experiences, the availability of control, and shifts in expectations. The study therefore focused on collecting data on both indoor and outdoor air temperature and humidity to show the comfort level in such buildings. By collecting data on 3 houses constructed of different materials the author aimed to show the effects of materials on thermal comfort. The analyses were further extended with computer simulations, which enabled restriction of the parameters on construction materials. The study has shown that in naturally ventilated residential buildings, construction materials affect both thermal comfort and thermal performance of the buildings. Buildings with traditional construction material showed a better performance in achieving the preferred thermal comfort while decreasing energy costs.

Licentiatavhandling (sammanfattning) Luleå : Luleå tekniska universitet, 2005. / Härtill 3 uppsatser + 2 appendix.

Lic.-avh. Luleå : Luleå tekniska univ., 2005.