Thesis (M.S.)--Oregon State University, 1982. / Map folded in pocket. Typescript (photocopy). Includes bibliographical references (leaves 61-65). Also available on the World Wide Web.

Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains ix, 110 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 90-94).

The results of a study to evaluate the behavior of a flexible culvert with the inclusion of a goefabric above the culvert are presented. In the soil-fabric-culvert system the geofabric becomes an interactive stress-carrying component of the system. Insight into the phenomenon of the stress-attenuation due to the inclusion of a semimechanical reinforcement, like geofabric, is also obtained from this research. The numerical technique of the finite element method is used for the analysis of the soil-fabric-culvert system. In the finite element model, two-dimensional triangular and quadrilateral elements having nonlinear, stress-dependent material properties are used for representing the soil. Beam elements are used to model the culvert, no-compression bar elements are used for the fabric, and two-dimensional interface elements for the contact surfaces between the soil and fabric. Incremental construction sequence and approximate nonlinear geometry are adapted in the analysis. Because of the relatively recent usage of fabrics for engineering purposes, no information regarding their employment as an inclusion in a soil-culvert system is available in the open literature. However, a review of the literature is conducted to bring out the current state of understanding of the behavior of soil-culvert systems without the presence of a fabric. The classical design concepts which reflect the development of the design methodology for flexible culverts are reviewed. The phenomenological concepts of soil-culvert interaction, particularly those of arching in the soil above the culvert and buckling of the soil-surrounded culvert wall are discussed. The burial depths of D/2 and D are considered for the horizontal configuration of the fabric when D = diameter of culvert. A burial depth of 2D is considered for the inclined configuration of the fabric. The following surface concentrated loading conditions are considered for the horizontal configuration of the fabric. Loads of 10 kip are placed symmetrically at S/D = 1/4, 1/2, 1, or 2 and 20 kip load at S/D = 0 (S = distance from vertical centerline of culvert). For the inclined configuration of the fabric above culvert, 50 kip surface concentrated loads are placed at S/D = 0, 1/4, and 1/2 simultaneously. This study shows that the fabric alters the stresses in the soil-fabric-culvert system by two mechanisms: the fabric can carry part of the load in tension and/or it can distribute the load more uniformly over a wider area. Under most practical conditions, the inclusion of fabric causes a significant reduction in the magnitudes of the following culvert design parameters: maximum axial force, maximum moment, vertical crown deflection, and horizontal springline deflection. The presence of fabric is more effective in attenuating the culvert design parameters for the location of surface loads within the horizontal projection of the culvert and for shallow depths of soil cover.

No description available.

Ministries and departments of transportation are working to undertake assessments of deteriorated metal culverts. To assist with these assessments by developing rational methods of classifying culverts, to select those requiring replacement or repair, the current thesis studied the effects of metal corrosion and backfill erosion on culvert stability. Finite element calculations were used to explain how stability is jeopardized by two forms of deterioration, both material failure (yield in the steel) and geometrical nonlinearity (bucking failure). The stability assessments are presented for structures designed using limit states design procedures in the Canadian Highway Bridge Design Code and the LRFD Bridge Design Code of the American Association of State Highway and Transportation Officials. It was found that yield in culverts in intact ground is proportional to plate thickness (thrust and moment are not affected). Buckling strength changes as corrosion occurs, but does not become critical in structures supported by good quality backfill (without erosion). Surprisingly, thrusts decrease when erosion develops adjacent to the culvert, and this implies that factor of safety against yield is increased. However, substantial decreases in buckling strength occur, and elastic instability can then become the critical performance limit after erosion. Three dimensional finite element analysis indicates that local buckling can develop before global buckling, for new structures featuring thin plates, or for thicker structures after corrosion. This form of elastic instability may not be safely estimated using current culvert buckling equations which consider global buckling. Local buckling results were not effectively estimated using the Bryn’s equation (the conventional method used for stiffened plate structures); therefore a preliminary design equation for assessment of local buckling is provided. After verifying the results obtained from this thesis with physical experiments, these findings can provide practitioners with useful evaluation tools for a quantitative assessment to the stability of buried culverts subjected to these two different kinds of deterioration (corrosion and erosion) in order to augment engineering experience or judgment, which is the primary tool currently being used. Moreover, the current study helps future experimental and numerical studies by investigating various significant deterioration scenarios, and the impacts of these scenarios. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-10-08 12:56:13.218

Thesis--University of Missouri, School of Mines and Metallurgy, 1892. / The entire thesis text is included in file. Holograph [Handwritten and illustrated in entirety by author]. Title from title screen of thesis/dissertation PDF file (viewed October 28, 2008)

Thesis (M.S.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 29-31). Also available on the World Wide Web.

Thesis (PhD)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Joel Cahoon. Includes bibliographical references (leaves 131-139).

Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Joel Cahoon. Includes bibliographical references (leaves 66-69).

Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains ix, 168 p. : ill. (some col.) Vita. Includes abstract. Includes bibliographical references (p. 148-167).