Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (M.S. in Engineering)--University of Texas at Austin, 2003. / Includes bibliographical references.

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"Conventional manufacturing methods are sub-optimal for nano-composites fabrication. Inhomogeneous dispersion of the secondary phase and scalability issues are the main issues. This work focuses on an innovative method where the reinforcement is formed in-situ in the melt. It involves the reaction of the molten aluminum with a nitrogen- bearing gas injected through the melt at around 1273 K. AlN particles are expected to form through this in situ reaction. A model has been developed to predict the amount of reinforced phase. Experiments have been carried out to confirm the feasibility of the process and the mechanism of AlN formation discussed. The detrimental effect of oxygen in the melt which hinders the nitridation reaction has been proved. The effect of process times and the addition of alloying elements (Mg and Si) have also been investigated."

This research targets Metakaolin as main material, with various kinds of combination materials and binder, and uses a mechanism to make colding metakaolin lightweight aggregate and then makes five different proportion of metakaolin lightweight aggregate, with an aim to know the effects of different proportion on aggregate through the destruction of point load , sift analysis , and unit weight. Choosing suitable aggregate based on ACI norm to set three groups of different water-cement ratio A(0.54)¡BB(0.46)¡BC(0.35) to mix into lightweight aggregate concrete, this is to find out the correlation between physical properties and mechanical behavior of metakaolin lightweight aggregate concrete through pressure resistance , splitting off , absorption capacities. The result shows that different proportions of metakaolin lightweight aggregate also take different effects, a suitable formula is selected in accordance with the application. Of all the groups, group D (cement¡Gslaked lime¡Gmetakaolin¡Gfly ash¡Gsand =12.5%¡G12.5%¡G28.125%¡G 9.375%¡G37.5%) has the best mechanical and physical performance. The mechanical properties such as pressure resistance and splitting strength of aggregate made from metakaolin lightweight aggregate concrete can meet up with CNS and ASTM norms, and it is superior to fly ash lightweight aggregate concrete.

For glass bottles to compete with plastic ones they need to be very much lighter. As their present weight is often constrained by their current strength, the glass they are made from needs to be very much stronger. In its virgin state glass is very strong, but handling bottles during manufacture introduces minute flaws, lowering their strength considerably. The aim of this work has been to gain a greater understanding of the meclianisms of thermal and mechanical damage and so to improve existing, and develop new hot glass handling materials which will reduce the amount of damage to the glass during hot-end handling To help gain an understanding of the interaction between thermal and mechanical damage mathematical modelling using finite difference techniques was utilised. Experimental investigations of how controlled contact, including thermal shock, weakened high strength glass were also undertaken. It was concluded from these investigations that the nearest to the ideal a real hot glass handling material could approach would be a material which produces mechanical damage which is limited to such a size that the thermal stresses produced by that material do not exacerbate the damage. A dimensionlessg roup was identified which helped to assessif a material had a selection of material properties which render it a likely hot glass handling material. Zirconium and Titanium were identified as possible hot glass handling materials. Carbon based materials proved to be the best handling materials but they have a limited life as they suffer oxidation in use. The oxidation resistance of various Carbon based materials was investigated with thermal gravimetric analysis and a test was designed to assess the strength retention of laminated Carbon-Carbon composites. Various coatings were developed to increase the life of existing hot glass handling materials. A Tit anium /graphite composite was developed in which the Titanium acted as an oxidation resistant skeleton and the graphite provided optimum glass handling ability.

Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / Kurtis, Kimberly E., Committee Co-Chair ; Kahn, Lawrence F., Committee Co-Chair ; Lai, James S., Committee Member ; Gokhale, Arun M., Committee Member ; Castrodale, Reid W., Committee Member. Vita.

Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on June 25, 2010). Bibliography: leaves 89-94.

Master of Science / Department of Civil Engineering / Robert J. Peterman / As of 2005, 23% of the bridges in the Kansas infrastructure are classified as structurally deficient or functionally obsolete according to the ASCE Infrastructure Report Card (ASCE, 2008). One alternative to replacing the entire bridge structure is replacing only the superstructure with lightweight concrete. This option is more economical for city, county, and state governments alike. Replacing the superstructure with lightweight concrete can oftentimes allow the bridge rating to be upgraded to higher load capacities or higher traffic volumes. Furthermore, lightweight concrete can be used initially in a bridge deck to provide reduced weight and a lower modulus of elasticity, therefore lower cracking potential. The Kansas Department of Transportation is interested in the potential benefits of using lightweight aggregate concrete in Kansas bridge decks and prestressed bridge girders. This research project used three types of lightweight aggregate to develop lightweight concrete mixtures for a bridge deck and for prestressed bridge girders. Two of the lightweight aggregates were expanded shale obtained locally from the Buildex Company. One deposit was located in Marquette, Kansas, and the other in New Market, Missouri. The third lightweight aggregate source was expanded slate obtained from the Stalite Company in North Carolina. Aggregate properties including absorption, gradation, and L.A. Abrasion were evaluated. Over 150 lightweight concrete mixtures were created and tested and several mix design variables such as water-to-cement ratio, cement content, and coarse-to-fine aggregate ratio were evaluated. From these results, optimized bridge deck and optimized prestressed concrete mixtures were developed for each type of lightweight aggregate. Special concerns for lightweight aggregate concrete are addressed. These optimized concrete mixtures were then tested for KDOT acceptability standards for the concrete properties of compressive strength, tensile strength, modulus of elasticity, freeze-thaw resistance, permeability, alkali-silica reactivity, drying shrinkage, and autogenous shrinkage. All concrete mixtures performed satisfactorily according to KDOT standards. In addition, an internal curing effect due to the moisture content of the lightweight aggregate was observed during the autogenous shrinkage test.