Applied Mechanics Commons^™

Numerical Computation Of Transient Response Of 2d Wedge Impact, Naresh Kumar Koyyapu

University of New Orleans Theses and Dissertations

The diverse applications of advanced marine craft ascribed to their high speed and technological advancements has led to the use of stronger and lighter metals in such crafts. High speed, in effect also increases slamming loads as higher speed increases frequency of wave encounter while operating in waves. The present study is limited to wedge impact models. Fundamentally, the study is thus about two-dimensional (2D) wedge impact in water. In an attempt to predict the structural response to impact hydrodynamic force, a beam element based finite element (FE) computer program is written and the results of the code are presented …

Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook

Electronic Theses and Dissertations

This dissertation is concerned with the development of robust numerical solution procedures for the generalized micromechanical analysis of linear and nonlinear constitutive behavior in heterogeneous materials. Although the methods developed are applicable in many engineering, geological, and materials science fields, three main areas are explored in this work. First, a numerical methodology is presented for the thermomechanical analysis of heterogeneous materials with a special focus on real polycrystalline microstructures obtained using electron backscatter diffraction techniques. Asymptotic expansion homogenization and finite element analysis are employed for micromechanical analysis of polycrystalline materials. Effective thermoelastic properties of polycrystalline materials are determined and compared …

Collapse Resistance Of Moment Resisting Frame And Shear Wall Rc Structural Systems Exposed To Blast, Alaa I. Chehab, Christopher D. Eamon, Joshua Griffin

Civil and Environmental Engineering Faculty Research Publications

Various characteristics of a structure influence its response when subjected to a blast load. This has important implications for survivability and resistance to progressive collapse. In this study, the effect of the type of lateral load resisting system on reinforced concrete building resistance to progressive collapse when exposed to blast load is examined. Fourteen different reinforced concrete structures were considered for analysis, with five structures designed as moment resisting frames and nine designed as shear walls systems. Buildings with 3, 6, and 10 stories with 3, 4, and 5-bay symmetric configurations were considered. The structures were exposed to external and …

Numerical Studies For Improving Fracture Toughness Resistance Curve Testing Using Single-Edge (Notched) Tension Specimens, Yifan Huang

Electronic Thesis and Dissertation Repository

The fracture toughness resistance curve, i.e. the J-integral resistance curve (J-R curve) or the crack tip opening displacement resistance (CTOD-R) curves, is widely used in the integrity assessment and strain-based design of energy pipelines with respect to planar defects (i.e. cracks). This thesis deals with issues related to the experimental determination of the J(CTOD)-R curves using the newly-developed single-edge (notched) tension (SE(T)) specimens. In the first study, the plastic geometry factor, i.e. the η_pl factor, used to evaluate J in a J-R curve test based on …

Experimental Building Demonstration Model With Viscous Fluid Dampers, Blake Thomas Reeve, Brianna Jean Kufa, Aden Malek Stepanians, Sophie Carmion Ratkovich

Architectural Engineering

The Architectural Engineering major places a heavy emphasis on structural dynamics and the role of wind and seismic loading in building analysis and design. Buildings of high importance that are critical to community function, such as hospitals, often utilize supplemental damping devices like supplemental viscous fluid dampers or base isolators to reduce the overall demands on the structural system. The design and analysis of these dampers are typically not taught at the undergraduate level, and is frequently performed by mechanical engineers, in lieu of structural engineers.

To better understand and research building behavior with supplemental damping devices, our multi-disciplinary team …

Evaluation Of Alternative Implementation Methods Of Failure Sampling Approach For Structural Reliability Analysis, Kapil Patki, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

In this paper, several alternative approaches are used to implement the failure sampling method for structural reliability analysis and are evaluated for effectiveness. Although no theoretical limitation exists as to the types of problems that failure sampling can solve, the method is most competitive for problems that cannot be accurately solved with reliability index-based approaches and for which simulation is needed. These problems tend to have non-smooth limit state boundaries or are otherwise highly nonlinear. Results from numerical integration and three extrapolation approaches using the generalized lambda distribution, Johnson's distribution, and generalized extreme value distribution are compared. A variety of …

Design Live Load Factor Calibration For Michigan Highway Bridges, Christopher D. Eamon, Valid Kamjoo, Kazuhiko Shinki

Civil and Environmental Engineering Faculty Research Publications

In this study, a reliability-based calibration of live load factors for bridge design specific to the State of Michigan was conducted. Two years of high frequency WIM data from 20 representative state-wide sites were analyzed, and load effects were generated for bridge spans from 6 to 122 m (20 to 400 ft), considering simple and continuous moments and shears, as well as single lane and two lane effects. Seventy-five year statistics for maximum live load were then estimated with probabilistic projection. Bridge girders considered for the calibration included composite steel, prestressed concrete, side-by-side and spread box beams, as well as …

Field Tests Of Two Prestressed Concrete Girder Bridges For Live Load Distribution And Moment Continuity, Christopher D. Eamon, Alaa Chehab, Gustavo Parra-Montesinos

Civil and Environmental Engineering Faculty Research Publications

Two similar bridges constructed with a live load continuous connection were tested for live load distribution and joint continuity. Girder distribution factors (GDFs) were compared to AASHTO equivalent values. For positive moments on all girders as for negative moments on interior girders, results using AASHTO equivalent GDFs were found to be generally conservative. However, for negative moments on exterior girders, test results exceeded AASHTO values, with 2-lane results significantly so. GDF results were verified with a FEA model, which produced similar behavior to the field tests. With respect to joint continuity, it is estimated that a simple span would produce …