ABSTRACT COMPARISON OF ANALYSIS METHODS OF EMBEDDED RETAINING WALLS HARMANDAR, Serkan M.S., Department of Civil Engineering Supervisor : Prof. Dr. Yener &Ouml / zkan Co -Supervisor : Dr. Oguz &Ccedil / aliSan December 2006, 123 pages In this study a single-propped embedded retaining wall supporting a cohesionless soil is investigated by four approaches, namely limit equilibrium, subgrade reaction, pseudo-finite element and finite element methods. Structural forces, such as strut loads, wall shear forces, bending moments are calculated by each method and results are compared. The analyses are carried for for three values of internal friction angle of soil / 30o, 35o, and 40o. Effects of modulus of soil elasticity of the backfill and wall stiffness on structural forces are investigated by using different values for these parameters. It is found that, in those of obtained by, limit equilibrium approach results in embedment depth greater than other methods. Minimum strut loads for the same soil and structure parameters are obtained by limit equilibrium method. An increase of Young&rsquo / s modulus of the soil results in decrease of the strut loads.

Aerospace research for next-generation travel increasingly focuses on the use of advanced composites to reduce weight and cost while retaining strength. One subset of materials with great potential is based on the combination of resin matrix and glass-fiber reinforcement. This research explores the application of a candidate nanopaper coating with a given composite. Prior research applied a set of given heat fluxes to the top surface of the composite for a set of given periods of time, and subsequently performed a 3-point flexural test to determine the elastic modulus for both the coated and uncoated composite for all of the combinations of heat flux and time. A finite element (FE) model is developed using the ANSYS general purpose finite element analysis (FEA) software that models the degradation in strength/stiffness properties based on heating condition and with the goal of predicting cracking using the element death feature in ANSYS. This thesis describes the prior research suggesting both the need for and novelty of this model, and the procedures used to form the model. The loading conditions of the 3-point flexural test are replicated, and four measures of accuracy are developed based on the force versus displacement curve of the test and the FE model. It is envisioned that continuum-level models developed as a part of these research be applied for design of next-generation space components These measurements are used to verify the FE model, and this model is then employed to extrapolate beyond the context of experimental conditions.