In the pharmaceutical industry uniform flow of powders is one of the most important considerations in solid dosage manufacture. Improper feeding of powders from storage hoppers into dye-presses can lead to inconsistent product quality, causing economic and health impacts. Investigation into the properties affecting powder flow is crucial. There were four objectives of the current research: 1. To determine the effect of moisture on the flow (Jenike flow index, Hausner Ratio and Carr Index, static and dynamic angle of repose) of selected pharmaceutical powders. 2. To study the effect of particle shape and size on Jenike flow index for selected starch and pharmaceutical powders. 3. To determine the effect of mixture compositions on the Jenike flow index of ordered mixtures of selected pharmaceutical powders. 4. To develop a novel flowability tester based on electrical capacitance tomography (ECT) that measures the dynamic angle of repose of powders.<p>To address the first objective, to determine the effect of moisture content on the flow of four pharmaceutical powders; an active pharmaceutical ingredient (API), aspartame, hydroxypropyl methylcellulose (HPMC), and Respitose® ML001 were selected. The API and Respitose® powders were found to be nonhygroscopic and were tested at near zero moisture contents only (in this case 0.31% and 0.19% respectively). Aspartame was tested at moisture contents of 0%, 2%, 5% and 8% and HPMC at moisture contents of 0%, 2%, 5% and 10%. Powder flowability was measured using the Jenike shear index, the Hausner Ratio, the Carr Index and the static and dynamic angles of repose. The Jenike flow index of aspartame increased from 0.885 to 3.65 with an increase in moisture content, which was attributed to the formation of large, round agglomerates. The Jenike flow index of HPMC decreased from 3.28 to 2.65 with an increase in moisture content, which was attributed to the increasing strength of liquid bridges. The Jenike flow index was the only flowability indicator to capture this complex behaviour. <p>In order to address the second objective, five starches (cow cockle, barley, rye, rice and tapioca), as well as four pharmaceutical ingredients (an API, aspartame, HPMC, and Respitose® ML001), were characterised for size and shape, and then tested for flowability. Powder flowability was measured using the Jenike shear test, the most widely accepted flowability standard in the pharmaceutical industry. It was found that the Jenike flow index decreased linearly with decreasing aspect ratio and decreasing roundness for the powders investigated. It was also determined that particle shape had a greater impact on flowability than size for powders under 30 microns in diameter. <p>To address the third objective, ordered mixtures of pharmaceutical powders were examined to determine their flowability. Six combinations of Respitose® ML001, hydroxypropyl methylcellulose (HPMC), and an active pharmaceutical ingredient (API) in varying concentrations were selected for investigation. Powder flowability was measured using the Jenike shear test, the most widely accepted flowability standard in the industry. The Jenike flow indices of the ordered mixtures were indistinguishable from the Jenike flow index of pure Respitose® at the alpha = 0.1 level.<p>The fourth objective, to develop a novel flowability tester using electrical capacitance tomography to measure the dynamic angle of repose, was investigated at the same time as the effect of moisture content. It was determined that the results of the novel dynamic angle of repose tester did not correlate well with the Jenike shear test. More development is needed before the novel flowability tester is ready for industrial use. The Jenike shear cell remains the only acceptable flow test for complex flow behaviour.

In the pharmaceutical industry uniform flow of powders is one of the most important considerations in solid dosage manufacture. Improper feeding of powders from storage hoppers into dye-presses can lead to inconsistent product quality, causing economic and health impacts. Investigation into the properties affecting powder flow is crucial. There were four objectives of the current research: 1. To determine the effect of moisture on the flow (Jenike flow index, Hausner Ratio and Carr Index, static and dynamic angle of repose) of selected pharmaceutical powders. 2. To study the effect of particle shape and size on Jenike flow index for selected starch and pharmaceutical powders. 3. To determine the effect of mixture compositions on the Jenike flow index of ordered mixtures of selected pharmaceutical powders. 4. To develop a novel flowability tester based on electrical capacitance tomography (ECT) that measures the dynamic angle of repose of powders.<p>To address the first objective, to determine the effect of moisture content on the flow of four pharmaceutical powders; an active pharmaceutical ingredient (API), aspartame, hydroxypropyl methylcellulose (HPMC), and Respitose® ML001 were selected. The API and Respitose® powders were found to be nonhygroscopic and were tested at near zero moisture contents only (in this case 0.31% and 0.19% respectively). Aspartame was tested at moisture contents of 0%, 2%, 5% and 8% and HPMC at moisture contents of 0%, 2%, 5% and 10%. Powder flowability was measured using the Jenike shear index, the Hausner Ratio, the Carr Index and the static and dynamic angles of repose. The Jenike flow index of aspartame increased from 0.885 to 3.65 with an increase in moisture content, which was attributed to the formation of large, round agglomerates. The Jenike flow index of HPMC decreased from 3.28 to 2.65 with an increase in moisture content, which was attributed to the increasing strength of liquid bridges. The Jenike flow index was the only flowability indicator to capture this complex behaviour. <p>In order to address the second objective, five starches (cow cockle, barley, rye, rice and tapioca), as well as four pharmaceutical ingredients (an API, aspartame, HPMC, and Respitose® ML001), were characterised for size and shape, and then tested for flowability. Powder flowability was measured using the Jenike shear test, the most widely accepted flowability standard in the pharmaceutical industry. It was found that the Jenike flow index decreased linearly with decreasing aspect ratio and decreasing roundness for the powders investigated. It was also determined that particle shape had a greater impact on flowability than size for powders under 30 microns in diameter. <p>To address the third objective, ordered mixtures of pharmaceutical powders were examined to determine their flowability. Six combinations of Respitose® ML001, hydroxypropyl methylcellulose (HPMC), and an active pharmaceutical ingredient (API) in varying concentrations were selected for investigation. Powder flowability was measured using the Jenike shear test, the most widely accepted flowability standard in the industry. The Jenike flow indices of the ordered mixtures were indistinguishable from the Jenike flow index of pure Respitose® at the alpha = 0.1 level.<p>The fourth objective, to develop a novel flowability tester using electrical capacitance tomography to measure the dynamic angle of repose, was investigated at the same time as the effect of moisture content. It was determined that the results of the novel dynamic angle of repose tester did not correlate well with the Jenike shear test. More development is needed before the novel flowability tester is ready for industrial use. The Jenike shear cell remains the only acceptable flow test for complex flow behaviour.

Experiments were carried out to study the effect of workmanship and environmental conditions on bond strength for concrete patch repairs. Four repair materials, sand/cement mortar, acrylic modified cementitious mortar, SBR modified cementitious mortar, and flowing concrete, were tested with mainly three test methods (core pull-off test, patch compressive test, and patch flexural test). At the beginning of this project, slant shear tests were also carried out. In the study of the effect of workmanship, the following parameters were included: surface roughness, surface cleanliness, surface soundness, moisture condition, application method, bond coat mistiming, repair material mistiming, and curing methods. In the study of the effect of environmental conditions, four parameters were considered: high temperature curing followed by drying shrinkage, high temperature curing followed by thermal cycling, low temperature curing, and low temperature curing followed by freeze/thaw cycling. A rougher surface produces a higher bond strength, but the increase depends on individual repair material. Sand/cement mortar favours a rough surface, but polymer modified mortars are not very sensitive to surface roughness. Environmental conditions affect the bond strength development, but the effect varies with each repair material. Test results suggest that low temperature curing should be avoided for polymer modified cementitious mortars. In addition to the experimental study, theoretical analyses were carried out to evaluate the available bond test methods. The evaluation was concentrated on answering the following questions: (1) What kind of factors will influence conductinga bond test? (2) What are the response of each factor involved to a specific test method? (3) What kind of influences are crucial in ensuring the full development of the bond strength? (4) Which factors are important to achieve a durable repair? and (5) What kind of a test can be used to monitor the quality of these crucial factors? In total, about 800 tests were conducted (500 core pull-off tests, 90 patch compressive tests, 100 patch flexural tests, and 80 slant shear tests).

The creep models of Sn/3.0Ag/0.5Cu solder material under tensile and shear loads are investigated in this study. The creep test results for Sn/3.0Ag/0.5Cu solder material with four operating temperatures, i.e. 120o, 135 o, 150 o and 165 oC are presented. The experimental results reveal that different creep equations are derived for the Sn/3.0Ag/0.5Cu solder material under tensile and shear loadings. The creep parameters, i.e. stress exponent, material constant and activation energy are curve fitted for the tensile and shear loading tests. The concept of failure toughness of solder ball joints is proposed and studied. The effects of high temperature aging and the thermal cycling loading on the failure toughness of different solder materials and ball sizes have also been explored. The difference between failure toughness values of traditional Sn/37Pb eutectic solder ball joints and the lead free Sn/3.0Ag/0.5Cu solder are compared and discussed. The results simulated from finite element method and experiment measurements under the ball shear test (BST) have been compared and studied. The variation stress, strain distributions and failure toughness during the ball shear testing are studied. The fracture behaviors of different ball joints under the high temperature aging and thermal cycles testing are examined and studied. The ball shear test results measured for the same size Sn/37Pb and Sn/3.0Ag/0.5Cu solder ball joints reveal different load-displacement variations. The relative ductility results are measured for the joint of Sn/37Pb solder ball. However, a high peak load and larger deformation are measured for Sn/3.0Ag/0.5Cu solder ball joints. Based on the definition of failure toughness proposed in this study, the higher failure toughness values are observed for the same size lead free Sn/3.0Ag/0.5Cu solder joints. The variation of failure toughness of different ball joints reveals that the high temperature aging and thermal cyclic loading reduce the failure toughness significantly. However, the measured failure toughness values indicate that the Sn/3.0Ag/0.5Cu solder joints have better ductility for the joints undergoing the high temperature aging and the thermal cycle loadings. Based on the measured results, the better reliability for the Sn/3.0Ag/0.5Cu ball joints is expected, due to the aging and cycling load testing.

Advanced composite materials are widely used for many structural applications in the aerospace/aircraft industries today. Joining of composite structures using adhesive bonding offers several advantages over traditional fastening methods. However, this technique is not yet employed for fastening the primary structures of aircrafts or space vehicles. There are several reasons for this: There are not any reliable non-destructive evaluation (NDE) methods that can quantify the strength of the bonds, and there are no certifications of quality assurance for inspecting the bond quality. Therefore, there is a significant need for an effective, reliable, easy to use NDE method for the analysis of composite adhesive joints. This research aimed to investigate an adhesively bonded composite-aluminum joints of variable bond strength using digital image correlation (DIC). There are many future possibilities in continuing this research work. As the application of composite materials and adhesive bond are increasing rapidly, the reliability of the composite structures using adhesive bond should quantified. Hence a lot of similar research using various adhesive bonds and materials can be conducted for characterizing the behavior of adhesive bond. The results obtained from this research will set the foundation for the development of ultrasonic DIC as a nondestructive approach for the evaluation of adhesive bond line.

Good bond strength between overlay and substrate is a key factor in performance of concrete repairs. This thesis was aimed at studying the evaluation of bond strength between repair material and substrate at the interface. Many factors such as surface roughness, existence of micro cracks, compaction, curing etc influence the bond strength. The quality assurance of the bond strength requires test methods that can quantify the bond strength as well as identify the failure mode. There have been numerous investigations led to development of different test methods. The forces which are applied in each test and the failure mode are important in order to choose the proper test. An interpretive study on test methods is presented. While this study can provide individually useful information on bond strength and bond characterization, it also contains discussions about each test and comparison of test methods.

AbstractThe Iosipescu shear test, also known as asymmetric four point bending of a V-notched beam,is frequently used for measuring in-plane shear properties of composites. The ASTM standard(ASTM D-5379-05) regulates how the test is to be performed. It prescribes a notch openingangle of 90° independently of the material tested, although this has proven to produceinhomogenous strain distributions in the test region (between the notches) for orthotropicmaterials. Commonly, strain gauges are attached in the center of the test region where thedeviation from average strain is high. Thus, systematic errors in the measurement in the rangeof 10% or more may be introduced. The modified Iosipescu shear test, presented in this thesis, uses a variable notch opening angledepending on the material orthotropy and orientation to accomplish even stress- and strainfields in the test region. The variable notch opening angle accommodates both anisotropicmaterials and their orientation. Based on an elastic rescaling theory for orthotropic materials,the geometry was rescaled to recreate the same stress distribution in the test region as forisotropic materials. Specifically the notch opening angle was rescaled depending on theorthotropic ratio, the ratio of the two in-plane principal stiffnesses (Ex/Ey), to obtain theoptimal notch geometry. The rescaling procedure has been verified numerically with FEsimulationsand experimentally for several materials of different orthotropic ratio showingthat this was a very feasible method. Using a whole field optical measurement system duringtesting, significantly more homogenous strain fields were observed than for the standardspecimen geometry. Thus, there is no longer any need for correction factors, relying on FEsimulation,to obtain correct shear moduli. Constitutive shear properties and strength can thusbe more accurately measured, more completely and with fewer sources of error. Notablyhigher shear strengths at larger strains were also recorded compared to standard testing.The function of the new fixture was evaluated and compared with the standard Wyomingfixture. Combined in-situ 3D deformation measurements of both the new fixture and thespecimen showed that out of plane specimen deformation was very low and substantiallylower than the Wyoming fixture. Thus considerably lower parasitic stresses are introducedwith the new fixture. Recommendations regarding fastening of the specimen were determined based on simpleanalysis combined with FE-calculations and experiments. For both isotropic and orthotropic itwas found favorable if the clamp load used to hold the specimen and the expected net peakload and were set about equal. This reduces the risk of failure outside the test region bycrushing, brushing, splitting and etc. The same effects as shown in the FE-simulations werealso observed experimentally and of similar relative magnitude.Problems with differences in strains arising on the front and back face of the specimen duringtesting have been frequently reported in the literature. This is believed to stem from deviationsfrom nominal specimen geometry such as non-parallel and/or non-perpendicular boundingsurfaces. Three types of these combinations were evaluated numerically and the two mostsignificant were confirmed experimentally. The most critical geometrical deviation assessedwas a specimen with slightly conical cross section in the gripping region. For both isotropicand orthotropic materials, very small deviations from nominal geometry, caused unacceptablylarge errors in measurements of constitutive behavior / QC 20100827

In this thesis, the relation between shear load and displacement for the lead-free solder (Sn3.0Ag0.5Cu) and the tin-lead solder (63Sn37Pb) are investigated. Except that, a new shear strength of the solder balls is suggested with considering the plastic strain energy of the solder balls. Three diameters of the Sn/Ag/Cu and Sn/Pb solder balls are studied. The variation of the plastic strain energies for the balls undergone different number of thermal cycles is compared. The effect of high temperature aging on the shear strength is also discussed. The difference between the failure fractures of the Sn/Ag/Cu and Sn/Pb solder ball are executed by using SEM. The experimental results show that the failure mechanism for the Sn/Ag/Cu is quite different from the Sn/Pb solder ball. Generally, the lead-free Sn/Ag/Cu solder is much ductile than the Sn/Pb solder ball in the shear test. Also the better fatigue performances are observed for the Sn/Ag/Cu solder balls.

The goal of this research is to investigate the behavior of polymer concrete confined with a carbon fiber sleeve used as a pile foundation. To evaluate the behavior of a confined polymer concrete pile in this research, four steps was considered. The first step of this investigation considered the mix design of polymer concrete, polymer concrete is a new material which is a combination of epoxy resin and aggregate. Instead of using a traditional mix of cement and water to make concrete, epoxy resin is used. Three dissimilar varieties of aggregate are mixed with different ratios in order to reach the maximum bulk density to obtain the maximum strength. After discovering the optimum ratio which gives the maximum bulk density, several samples of the aggregate are mixed with different ratios of epoxy resin. Next, the samples are investigated in a compression test to observe which ratios have the maximum strength and this ratio is used for a polymer concrete mix design to create a pile foundation. The pile is a built using a cast in place method and confined with a sleeve of carbon fiber. The second part of this investigation determined the structural mechanical properties of confined polymer concrete pile material. The unconfined and confined polymer concrete was tested in compression to determine compressive strength and stress-strain behavior. Similar tests were conducted on unconfined and confined cement concrete for comparison between these materials. Additional tension tests were conducted on unconfined polymer concrete. Then, a carbon fiber sleeve was tested in compression test to determine tensile strength and tension stress-strain behavior. After these tests, the confined polymer concrete is modeled in the computer program MATTCAD which is used to calculate the theoretical bending moment capacity and load-displacement curve. Finally, the confined polymer concrete is tested with the MTS 311 Load Frame in three point load flexure test to determine the experimentally bending moment capacity, load-displacement curve and compare with theoretical results. Confined polymer concrete was tested in one and two way cyclic loading to observe the ductility behavior of this material as laterally loaded piles and compared with cement concrete results in cyclic loading. The third part of this investigation determined the geotechnical mechanical properties of confined polymer concrete pile material. Cyclic Multi Degree of Freedom (CYMDOF) device was used to determine interface reaction and friction angle between confined polymer concrete and soil with interface shear test theory method. Furthermore, the same device was used to determine the friction angle of soil with direct shear test theory, and compare the friction angle results together. The last part of this investigation considered the behavior of different sized confined polymer concrete pile in different types of soil. A confined polymer concrete pile was modeled into PLAXIS and OPENSEES PL computer software to analysis pile in axial load and lateral load respectively. Furthermore, a cement concrete pile was modeled with similar software and conditions to compare these two materials.

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