No description available.

Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed February 12, 2008) Includes bibliographical references.

Thesis (M.S. in civil engineering)--Washington State University, May 2008. / Includes bibliographical references (p. 69-70).

Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2002. / "June 2002" Includes bibliographical references (leaves 349-374).

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 334-340).

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 330-341). Also available in electronic version.

Thirty full scale prestressed concrete struts all having a slenderness ratio of L/D = 40 were tested with three different eccentricities. Stress-strain curves of the corresponding test cylinders were established and the Young's Moduli evaluated. The specimens were fabricated with different percentages of prestressing steel ranging from 0.23 to 1.20%. The initial prestressing forces were set to obtain a final prestress of 140,000 psi in all specimens. The dimensions of the struts, and the quality and manufacturing process of the concrete, were kept constant. Special adjustable supporting devices simulated ideal hinged conditions. The struts were tested to their ultimate capacity and their critical buckling loads were evaluated. The tests proved that, provided the column is made of high quality concrete, the critical load values can be obtained by using Euler's fundamental formula, and these values are independent of the amount of prestressing. For eccentrically loaded struts maximum stresses from a modified secant formula, incorporating effect of prestressing, were compared with those calculated on basis of observed deflections. According to the test results the secant modulus corresponding to the average compressive stress should be used in Euler's formula. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

No description available.

Thesis. 1977. M.S.--Massachusetts Institute of Technology. Dept. of Civil Engineering. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography : leaves 130-132. / M.S.

This thesis investigates the behaviour of hollow and concrete filled steel columns fabricated from thin steel plates. The columns are investigated under axial, uniaxial and biaxial loading. The currently available international standards for composite structures are limited to the design of concrete filled steel columns with compact sections and yield stress of steel up to 460 N/mm2. This thesis consists of both experimental and analytical studies and design recommendations for future use. Three comprehensive series of experimental tests are conducted on hollow and concrete filled steel columns. The principal parameters that have been considered in the test programmes are the slenderness of the component plates, the yield stress of the steel and the loading conditions. In the first test series, three slender hollow steel columns and three slender composite columns are tested under uniaxial loading. The steel utilised is mild steel. High strength steel is utilised in the second test programme. In this test series four stub columns, eight short columns and eight slender columns are tested, each set consists of four hollow and four composite columns. Short columns are tested under axial loading to investigate the confinement effect provided by the steel casing. Slender columns are tested under uniaxial loading to investigate the coupled instability of local and global buckling. The third test programme is quite novel and considers the behaviour of hollow and concrete filled steel columns fabricated with high strength structural steel plate and subjected to biaxial bending. In this test eight short columns and ten slender columns each of them consisting of hollow and composite columns are investigated under biaxial loading. Analytical models are developed herein to elucidate the behaviour of the hollow and composite columns considering cross section slenderness, yield stress and loading conditions. An iterative model considering the coupled global and local buckling in the elastic and plastic range incorporating material nonlinearities is developed to investigate the behaviour of slender columns fabricated from mild steel. An improved deformation control model is developed to investigate the behaviour of slender high strength steel columns considering the confinement effect and local and post-local buckling in the elastic and plastic range. Then a numerical model for biaxial bending is developed to study the behaviour of short and slender concrete filled high strength steel columns under biaxial loading incorporating interaction buckling considering material and geometric nonlinearities. The scope of the thesis presents a wide range of experimental and theoretical studies of an extremely novel nature. It demonstrates the benefit of confinement and the consideration of local and post-local buckling in the elastic and plastic range. It is hoped that this research will contribute to the area of composite steel-concrete structural applications.