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The work in this thesis examines the suitability of utilising ground waste brick as a cement replacement material. The brick types investigated were obtained from the UK,Denmark, Lithuania and Poland. Cement was partially replaced by various quantities and types of ground brick in mortar and concrete. Compressive strength, pore size distribution and sorptivity of mortar generally all benefit from the presence of ground brick and the greatest effect can be seen after water curing for one year. Compressive strength of concrete is also shown to increase as the fineness of ground brick increases although the optimum particle size for ground brick in concrete is still to be determined. The ground bricks investigated have a significant effect on the performance of ground brick mortar when exposed to sodium sulphate solution and synthetic seawater. It is seen that depending on the chemical and phase composition, the effect of ground brick can increase substantially the rate of deterioration of mortar or can reduce significantly the expansion observed. No definite mechanism was identified as being responsible for the observed deterioration of mortar exposed to sodium sulphate solution although it seems likely that water intake due to ettringite formation and adsorption of water by the resultant colloidal product are the primary causes of expansion. Sulphate content, glass content and oxide chemistry of brick are key factors as to its performance when used as a cement replacement material in mortar. Bricks with a high proportion of low calcium glass make very effective pozzolans. Bricks with high calcium glass or a low proportion of glass should not be used as pozzolans. Small amounts of sulphate in ground brick do not have any serious deleterious effects on ground brick mortars and can be beneficial. It is established that it is technically feasible to partially replace cement with ground brick in mortar and concrete, depending on its chemical and phase composition to produce a more durable, cost effective and (due to the lower cement content) a less environmentally damaging material than that produced without cement replacement.

Corrugated boxes are relatively inexpensive and used extensively to contain and protect consumer products as they move through the distribution system, providing a much-needed function in today’s economy. Also, corrugated boxes are constructed from paper, which is affected by ambient moisture in the atmosphere. Relative humidity regularly varies between 30 to 90 percent depending on location and time of year. Above a relative humidity of 30 percent, paper fibers are affected, resulting in a decrease in the top-to-bottom compression strength of corrugated boxes. Therefore, understanding the moisture effect on box compression strength is essential. The goal of this study is to characterize the effect of relative humidity and, subsequently, the effects of moisture content on the compressive resistance of corrugated board boxes. A total of 3,000 industry supplied boxes are used to evaluate moisture content and compressive strength at seven relative humidity conditions from 30 to 90 percent. Three sets of conditions are repeated to test repeatability for a total of ten batches tested overall. Preconditioning and conditioning of all specimens meet or exceed the requirements of TAPPI T402. All specimens are compression tested by following TAPPI T804. Further, all compression testing is performed in an environmental chamber at test conditions to ensure uniformity. The moisture content for three out of every ten specimens is recorded using a loss-upon-drying moisture balance. Results indicate a second-order polynomial increase in moisture content as a function of relative humidity. The compression strength of corrugated boxes is found to vary linearly with moisture content for the range tested and follows a second-order polynomial decrease with increasing relative humidity. The data from this study are compiled into a table of corrugated box strength reduction factors for comparison with the results from previous studies.

Abstract: With the ever increasing concerns about the structural adequacy of buildings and infrastructures, particularly in harsh environments with limited funding for ongoing maintenance, a significant need exists to develop highly durable and rapidly constructed structural systems. To this aim, recent advances in the development of high-performance material allow for the introduction of innovative girder configuration systems using the ultra-high performance fiber-reinforced concrete (UHPFRC) material as flange and direct embedded steel plate as web. The proposed composite member will result in a durable building or bridge superstructure construction with reduced life-cycle cost, longer life span, and enhanced environmental sustainability (Hegger 2006, Graybeal and Tanesi 2007, and Rauscher 2011). To cope with the higher cost of the high-performance material, innovative designs should be implemented in detailing of composite members to make sure that the material is best used where it is most required. To date, however, there has been very limited research on the structural behaviour of this member configuration. The objectives of the current study are twofold. The first phase focuses on development of a UHPFRC material incorporating 0-5% randomly distributed short steel fibers using the conventional moist curing technique without added heat or pressure to be representative of potential applications requiring in-situ casting. The addition of steel fibers to the UHPFRC matrix was found to significantly enhance the mechanical properties of the UHPFRC material in compression, flexure, tension and shear. In addition, the peak compressive, flexural, equivalent tensile strength, and shear strengths of the material were found to decrease with an increase in the specimen size, indicating that a size effect exists for members constructed with UHPFRC material. The second phase of the research focuses on the development of a composite connection system, which ensures an efficient composite action between embedded steel web and concrete flanges. A commercially available finite element package, ABAQUS® 6.11 was used to simulate the response of the composite connection system subjected to the pull-out load and to minimize the need for full-scale structural testing. A total of 42 specimens were designed, constructed, and tested to capture the experimental response of the composite connections subjected to the pull-out loading. The influence on the pull-out capacity of the composite connection from shape and size of holes (which is cut through the embedded web), embedded length of steel plate, plate thickness, fiber content, double headed stud (which is passed through hole), and concrete member depth are investigated. In addition, comparisons of the connection specimen performance to those constructed with conventional fiber-reinforced concrete (FRC) material were completed. It was found that compared to connection systems constructed with FRC material, the use of UHPFRC can substantially enhance the load carrying capacity and ductility of the connection systems subjected to the pull-out and push-out loading.

The purpose of this study was to examine the compression strength of the corrugated shipping containers having the conventional purpose hand holes and the arc top hand holes. Generally, the arc top hand hole has stronger tear strength than the conventional purpose hand hole, but the arc top hand hole has a larger opening area than the conventional purpose hand hole, and the larger opening area needs more space of a dispersion of compression stress to increase compression resistance. However, when a hand hole has enough space to distribute compression stress, the only one variable is the width of the opening area in shipping containers if the containers have the same dimensions. In this study, two designs of the hand hole have the same width of opening area and are located to have enough space to distribute compression stress. As a result, the resistance forces of containers are the same in each different environment.