Engineering Commons^™

Behavior Of High Strength Concrete And Slender Reinforced Concrete Columns With And Without Steel Fibers, Lin Showmay Hsu

Dissertations

A series of compression tests are conducted on 3 in. by 6 in. cylindrical specimens using a modified testing method that give the complete stress-strain behavior for both plain and fibrous high strength concretes with or without tie confinements. The volume fractions of fiber in the concrete are 0%, 0.5%, 0.75%, and 1.0%, respectively. Empirical equations are proposed herein to represent the complete stress-strain relationships of high strength and high strength fibrous concretes with compressive strength exceeding 10,000 psi. Various parameters are studied and their relationships are experimentally determined. The comparison between the experimental and analytical results shows to have …

The Influence Of Pore Fluids On Shear Strength And Stress-Strain Behavior Of Granular Soils, Prasanna Ratnaweera

Dissertations

When a dry granular soil is subjected to an external load, the stresses are transferred through mineral to mineral contacts. The shear strength of such a soil is governed by its contact properties. Presence of a thin layer of fluid between mineral to mineral contacts in a saturated soil will alter its contact properties. Therefore any change in the physical properties of pore fluid can logically be reasoned to influence the deformation characteristics of granular soils.

To investigate the influence of pore fluid viscosity on shear strength and stress-strain behavior of a soil, a series of consolidated drained triaxial tests …

Three-Dimensional Beam-Columns, Mohammad Hassan Shams

Theses

This thesis explores several special cases of three-dimensional beam-columns and suggests that the method of finite differences can be used when a solution of general case is required. The thesis begins with a review of the three-dimensional beam-column equations and then shows how these equations can be used to generate the member stiffness matrix for the nonlinear analysis of three-dimensional frames. Examples are included which discuss the differences between the analytical and numerical solutions.

The Collapse Of The Cypress Viaduct During The Loma Prieta Earthquake Of October 17, 1989, Mohamed M. Eid

Theses

The Loma Prieta earthquake of October 17, 1989 in California was one of the most disastrous earthquakes in U.S history. It caused damage to commercial, residential, and industrial structures, transportation and utilities.

This study includes investigations about the Cypress Viaduct collapse re?ported by:

1. California Governor's Board of Inquiry [4].
2. National Institute of Standards and Technology (NEL) W.
3. 3The Author.

Investigators in the first report concluded that the collapse was due to horizontal ground motion. In the second one, it was due to the vertical ground motion.

In the author's investigation, a detailed static and dynamic analyses are performed to determine …

The Use Of Laboratory Testing To Understand The Behavior Of Collapsible Soil Upon Wetting, Martha H. Denham

Dissertations and Theses

In developing a constitutive model that could predict the settlement due to the collapse, several goals needed to be met. These were to gain an understanding of the collapse phenomenon, knowing the soil properties at the natural water content and how they change after collapse, and develop and test the new model. It was felt that laboratory testing could be of use. The types of test conducted included use of the Oedometer, Pressuremeter, and Triaxial tests. The material that was used for the testing was a "generic" soil manufactured out of diatomite. In all of the tests the soil was …

A Modified Approach To Flood Prediction In Urban Watersheds, Joseph Ofungwu

Dissertations

The purpose of this dissertation was to develop a better method for dealing with the problems of flood prediction in Urban Watersheds. It has long been realized that urbanization activity such as increased imperviousness, drainage improvements, etc. increases runoff volumes. Therefore, traditional flood prediction methods using the Log Pearson III distribution underestimate flood frequencies when applied to urban watersheds without modification.

In attempt to compensate for the effects of urbanization on streamflow, previous workers usually employed regional analysis techniques involving a number of different watersheds at various degrees of urbanization. Results obtained by this approach leave room for improvement primarily …

Inelastic Stability Of Nonproportionally Loaded Steel Sway Beam-Columns And Space Frames, Saleh Ali Eidan

Civil & Environmental Engineering Theses & Dissertations

A comprehensive study of the inelastic stability of steel beam-columns and frames subjected to nonproportional loads is conducted. A set of materially nonlinear differential equations of equilibrium for planar and biaxially loaded beam-columns are first formulated including sidesway. The analysis includes the effect of flexible connections, and initial imperfections in the form of member crookedness and residual stresses. Also, hollow rectangular sections are adopted for the study. First, an iterative numerical solution procedure is formulated for sway beam-columns utilizing central finite-differences with second-order truncation errors. Next, using the beam-column analysis, an inelastic frame analysis procedure is formulated by a conversion …

Materially Nonlinear Finite Element Analyses Of Trusses And Slab-On-Grade Problems, Moayyad Moh'd Al-Nasra

Civil & Environmental Engineering Theses & Dissertations

The overall approach is to employ the finite-element method along with specified material models to account for material nonlinearity. This study includes two different applications: truss structures and slabs-on-grade.

Procedures for materially nonlinear analysis of truss structures, which apply for both determinate and indeterminate cases are proposed. The proposed procedures are simple and can handle a variety of different stress-strain functions, and the applied load does not have to be incremental. Proposed procedures results are verified with the output of NASTRAN.

A finite-element model for slab-on-grade is introduced. The concrete slab is represented by eight-node brick elements, and the joints …

Improved Methodology For Limit States Finite Element Analysis Of Lattice Type Structures Using Nonlinear Post-Buckling Member Performance, Markus Ostendorp

Dissertations and Theses

In an attempt to achieve more efficient designs, the technological frontier is pushed further and further. Every year science probes for a better understanding of natural phenomena, discovering new and improved methods to perform the same task more efficiently and with better results. One of the new technologies is the nonlinear analysis of structural systems using inelastic post-buckling member performance. Inelastic post-buckling member performance is defined as the constitutive relationship between axial load and displacement after the ultimate member capacity has been exceeded. A nonlinear analysis is able to predict the failure behavior of a structural system under ultimate loads …

Seismic Response Of Pipeline Systems In A Soil Liquefaction Environment, Hongzhi Zhang

Civil & Environmental Engineering Theses & Dissertations

This research is a study of the general seismic response behavior of buried pipeline systems during a soil liquefaction process. To aid the design of buried pipelines in a soil liquefaction environment, the purpose of this research is to provide the basic dynamic seismic response of different pipeline systems. Several important parameters such as pipe diameter, buried depth, additional mass and the size of the liquefiable soil zone have been introduced. The pipeline systems under study are cross-types, T-types and straight pipelines, with or without a manhole, buried in a soil liquefiable zone.

Time-varying soil spring constants are used for …

Express Transit Service For The University Of Central Florida, Arturo J. Perez

Retrospective Theses and Dissertations

As one of the fastest growing universities in the State of Florida, the University of Central Florida (UCF) is faced with the hardships placed on higher learning institutions across the nation. The increase of students paralleled by the increase of motor vehicles on the university campus, and the shortage of funding needed to construct the necessary parking facilities to support this growth, has left the University with a big dilemma, whether to try to overcome the parking space deficit by building the needed spaces to accommodate the demand, or provide a mass transit system that would reduce the number of …