The composite action of a bridge deck and girder is essential to the optimization of the superstructure. The transfer of forces in the deck to the girders is done across a shear interface between the two elements. The transfer occurs through the cohesion of the concrete at the interface and then through the shear reinforcement across the interface. Adequate shear strength is essential to the success of the superstructure. A collection of 537 horizontal shear tests comprised the database for the study of various concrete types and interface surface treatments. The predicted horizontal shear strength calculated from the AASHTO LFRD bridge design code was compared to the measured shear strength. The professional bias was computed for each specimen. The professional biases, standard deviations, and coefficients of variation for each category were calculated. The material properties factor along with fabrication factor was researched. The loading factors were researched and calculated for use in calculating the reliability index. The final step was to compute the reliability index for each category. The process was repeated to learn the reliability of the equation proposed by Wallenfelsz. The results showed that the reliability index for the AASHTO LRFD horizontal shear strength equation wash much lower than the desired target reliability index of 3.5. The reliability index for the Wallenfelsz equation was higher but still not close to the target reliability index. / Master of Science

No / Much of the environmental impact of buildings is associated with consumption of resources and generation of waste. The construction industry in Europe consumes over 70,000 million tonnes of a wide range of materials each year, and generates over 250 million tonnes of waste. Reducing waste is a priority for all the European Governments. Composite flooring formed by connecting the concrete slabs to the supporting steel beams has been widely used for many years throughout the world. The use of composite action between steel and concrete is well established as a cost-effective arrangement for floor systems in multi-storey steel frame building structures. Composite action between steel beams and concrete slabs through the use of shear connectors are responsible for a considerable increases in the load-bearing capacity and stiffness of the steel beams, which when utilised in design, can result in significant savings in steel weight and construction cost. However, shear connectors are welded through the steel decking and cast into the concrete; this made deconstruction and reuse of the steel components almost impossible. A demountable shear connector is developed and tested to assess its potential and suitability in term of replacing the welded through headed shear studs. Test results shown that these shear connectors can be easily demounted after test and have a similar capacity and behaviour of the welded shear connectors. In addition, test results showed that the new demountable shear connectors process high ductility in comparison with the welded shear connectors.

published_or_final_version / abstract / Mechanical Engineering / Doctoral / Doctor of Philosophy

Block shear is a mode of failure in which a steel member fails in tension along one plane and shear on a perpendicular plane along the fasteners. The design process for block shear has been at the center of debate since it first appeared in the 1978 AISC Specification and has evolved over the years. This thesis investigated the block shear design equations as they have progressively changed from the 1978 provisions for Allowable Stress Design (ASD) to the 2005 provisions for Load and Resistance Factor Design (LRFD). Block shear strength capacities were calculated for multiple designs involving coped beams, angles, and structural tees. These analytical values were compared to physical test findings available in the literature. The results of this study compare the different strength predictions to one another, as well as benchmark the AISC provisions to actual physical testing strengths. The comparisons were also used to determine whether the ASD and LRFD specifications follow similar trends. Good agreement between the predicted capacities and the results from physical testing was observed for a majority of the geometries investigated. However, capacity predictions based on increasing the number of rows of bolts for a coped beam and changing the length of the outstanding leg for an angle or tee connection were found to disagree with the test results. A finite element study was also completed to further explore the influence of changing the length of the outstanding leg of tee connections because these geometries showed considerable disagreement between the calculated capacities and the test data.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

No description available.

No description available.

Thesis (M.S. in civil engineering)--Washington State University, August 2009. / Title from PDF title page (viewed on Aug. 11, 2009). "Department of Civil and Environmental Engineering." Includes bibliographical references.

Thesis (M.S.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (December 12, 2006) Includes bibliographical references.

Made available in DSpace on 2014-06-11T19:27:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-11Bitstream added on 2014-06-13T19:34:58Z : No. of bitstreams: 1 roel_p_me_guara.pdf: 1239092 bytes, checksum: e604f05f6643d5209f943625d3855dfb (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O ensaio de tração fora do eixo de simetria, conhecido como ensaio off-axis, trata-se de um método utilizado para identificação do comportamento ao cisalhamento de um determinado material. Neste ensaio os eixos de simetria do material fazem um ângulo com os eixos do corpo de prova. Este ensaio foi proposto com o intuito de extrair o efeito não uniforme da distribuição de tensões que ocorrem no centro do corpo de prova, que naturalmente estão presentes nos ensaios normalizados para o cisalhamento. Os ensaios normalizados consideram a hipótese das tensões serem distribuídas uniformemente, porém desde que o material começa a cisalhar e até a ruptura esta situação não ocorre nestas condições. A proposta deste trabalho é investigar o comportamento ao cisalhamento da madeira de Eucalyptus citriodora através do ensaio off-axis. Com o método dos elementos finitos e o programa comercial ANSYS 9.0 ED ®, foi possível fazer uma simulação numérica do ensaio off-axis para a madeira de Eucalyptus citriodora, que trata-se de uma madeira com alta densidade, e com isso avaliar a aplicação deste ensaio para esta espécie de madeira também, pois na literatura encontram-se aplicações deste ensaio somente para madeiras com baixas densidades. Finalmente, com base nos resultados obtido desta simulação, que trata-se de uma abordagem não destrutiva, foi possível realizar o ensaio offaxis para esta espécie de madeira para obter o seu módulo de cisalhamento. Os resultados obtidos com a simulação mostraram que a distribuição das tensões e deformações são homogêneas no centro do corpo de prova e o valor de módulo de cisalhamento obtido é coerente com o resultado obtido na literatura / The test off-axis of symmetry, known as test off-axis, it is a method used to identify the shear behavior of the determined material. This test the axis of symmetry of the material make an angle with the axis of the specimen. This test was proposed in order extract the effect is nouniform the stress distribution occurring in center of specimen, that naturally appear standardized tests of the shear. The standardized tests consider the hypothesis tension to be distributed evenly, however the shear until failure doesn´t occur under these conditions, due coupling of stress different. The purpose of this study is to investigate the shear behavior of Eucalyptus citriodora through testing off-axis. With the finite element method and the commercial program ANSYS 9.0 ED ®, it was possible to test numerical simulation of off-axis for the timber of Eucalyptus, that it is a timber with high density, and thus evaluate the implementation of this test for this species of wood, too, because in the literature are applications of this test only for woods with low densities. Finally, based on results obtained from this simulation that it is a non-destructive, it was possible to perform the test off-axis for this species of wood to get its shear modulus. The results obtained with the simulation showed that the distribution of stresses and strains are homogeneous at the center of the specimen and the value of shear modulus obtained is consistent with the result obtained in the literature