This study presents experimental results from nine large-scale circular concrete columns reinforced with longitudinal and transverse glass fiber-reinforced polymer (GFRP) bars. These specimens were tested under lateral cyclic quasi-static loading while simultaneously subjected to constant axial load. Based on the measured hysteretic loops of moment vs. curvature and shear vs. tip deflection relationships, a series of parameters related to ductility and flexural strength are used to evaluate the seismic behavior of each column. The results showed that concrete columns reinforced with GFRP bars have stable post-peak branches and can achieve very high levels of deformability. Longitudinal GFRP bars maintained their stiffness at high strains and transverse GFRP spirals provided increasing confinement for the entire duration of the test without any spiral damage. The tests showed that, as an innovative material with excellent corrosion resistance GFRP bars can be successfully used as internal reinforcement in ductile concrete columns.

This study presents experimental results from nine large-scale circular concrete columns reinforced with longitudinal and transverse glass fiber-reinforced polymer (GFRP) bars. These specimens were tested under lateral cyclic quasi-static loading while simultaneously subjected to constant axial load. Based on the measured hysteretic loops of moment vs. curvature and shear vs. tip deflection relationships, a series of parameters related to ductility and flexural strength are used to evaluate the seismic behavior of each column. The results showed that concrete columns reinforced with GFRP bars have stable post-peak branches and can achieve very high levels of deformability. Longitudinal GFRP bars maintained their stiffness at high strains and transverse GFRP spirals provided increasing confinement for the entire duration of the test without any spiral damage. The tests showed that, as an innovative material with excellent corrosion resistance GFRP bars can be successfully used as internal reinforcement in ductile concrete columns.

The study was an attempt to determine if a significant change in behavior would occur when a "token economy" was instituted on an open ward. Schizophrenic patients in the token system that resided on one ward were compared with control patients on other wards on a number of desired behaviors. Results indicated an overall increase in the frequency of desired responses when the token reinforcement was initiated. The study also suggests some problem areas involved when instituting and maintaining a token economy in a state hospital.

Religiosity and morality constitute the fundamental components of any culture and set up rules and regulate interpersonal behavior. In the context of religion, to understanding value transgressions, their emotional consequences and the moderating role of social threats (in-group and out-group interactions), the psychological underpinnings of value-reinforcement, and complementing role of self-affirmation at a group level represent the focal points of this dissertation. The findings of study 1 show that value transgression has a direct effect on the level of negative emotion experienced by the transgressor. The social threat that is manipulated by the presence of an out-group member during the time of transgression moderates the relationship between value transgression and level of negative emotion. Furthermore, value reinforcement (e.g, endorsing group value) can weaken the effect of threats and mitigate negative emotions. Study 1 findings show that value reinforcement's absence qualified previous proposition of value transgression and social presence interaction. In study 2, I carry on the investigation by showing that granting opportunities to affirm important group values mitigates their emotional tension. Study 2 results show that group-affirmation may work as a complementary factor that further explains the relationship between value reinforcement and emotional reaction in the event of transgressing group values.

No description available.

No description available.

In most industrialized countries, significant future activity in the construction sector will be related to repair and rehabilitation of aging infrastructure. This will require use of durable and high performance repair materials. Among various mechanisms cited for lack of durability in repairs, early-age shrinkage cracking in overlay materials is of utmost importance. Fiber-reinforcement can be used to alleviate some of the issues related to plastic shrinkage. However, quantifying the performance of cement-based composites under restrained shrinkage conditions remains an issue. Various test techniques are available to measure free and restrained shrinkage, but do not simulate the real constraint imposed by the substrate on the overlay. In this dissertation, an innovative test method called the bonded overlay technique is described. An overlay of fiber-reinforced material to be tested is cast directly on a substrate, and the entire assembly is subjected to controlled drying. Cracking in the overlay is then monitored and characterized. During the development of this test method, instrumentation was included to enable measurement of the crack propagation rate using image analysis, evaporation rate, heat development, and strain using embedded sensors. Using the above technique, the effect of mix proportion including variables such as water-cement ratio (w/c), sand-cement ratio (s/c), and coarse aggregate content were studied. An increase in w/c from 0.35 to 0.6 significantly increased the total cracking. Addition of coarse aggregates reduced shrinkage cracking, however, for the range of s/c investigated, no definite conclusions could be drawn. Mixes with 0-20% fly ash and a 7 lit/m3 dosage of shrinkage reducing admixtures indicated no significant reduction in cracking. The influence of fiber geometry on cracking in overlays was also investigated. Fiber types included different sizes of polypropylene and cellulose fibers and one type of glass fiber (volume fraction ranging between 0-0.4%). Glass fibers at a small dosage of 0.1% were the most efficient fiber and completely eliminated cracking. Of the two field projects considered: one was a plaza deck at the UBC Aquatic Center, where cellulose fibers were used, and the second at the UBC ChemBioE building, where polypropylene fibers were used in slabs-on-grade. Both overlays were instrumented with strain sensors, data from which were monitored over the Internet. Results clearly indicated that fibers reduced the strain development in fiber-reinforced overlays when compared to un-reinforced overlays. An energy-based fracture model was proposed to predict maximum crack widths and in a second study, an equation was proposed to correlate early-age shrinkage and flexural toughness of cellulose fibers. In both models, a reasonable correlation with the test data was observed. In addition, factorial design method was used and a mathematical model was proposed to correlate different variables such as w/c, s/c, and fiber dosage.

296 leaves : ill. ; 27 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Psychology, 1974

Thesis (M.S.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Thesis (B.A. Hons. 1970) from the Department of Psychology, University of Adelaide.