Engineering Commons^™

Two-Dimensional Computer Modeling Of Joints And Fractures In Continua, Royd R. Nelson

Theses and Dissertations

This thesis presents a numerical formulation which incorporates the effects of joints, cracks, and fractures into a mathematical mode used to in an existing finite element code. Two separate crack definitions were incorporated, one involving a discrete crack model, and the other a continuum approach defining a new material with regularly spaced joints. Several examples are also presented demonstrating the use of this capability.

Development Of A Computer-Aided Graphics Capability To Display Field Test Data, L. Allen Adams

Theses and Dissertations

This thesis develops an interactive computer-aided graphics package for the display of experimental and field test data. EXPERT was developed to be used in conjunction with MOVIE.BYU and DISSPLA, utilizing a bivariate interpolation scheme to create a full field of data using the "sparse" field data as pivotal points. The usefulness and practicality of the program is demonstrated by graphically displaying the data from the Air Force Weapons Laboratory's CHEAT test.

Behavior Of Channel-Shaped Reinforced Concrete Columns Under Combined Biaxial Bending And Compression, Dureseti Chidambarrao

Theses

The inelastic behavior of irregular shaped reinforced concrete columns has been a constant concern for a structural engineer, to design a safe and economic structure in modern buildings and bridge piers. The shape of the elements in a reinforced concrete structure may be used to optimize its structural strength, to make better use of the available space, to improve the aesthetic appearance of the structure, or to facilitate construction. Due to the locations of the columns, the shapes of the buildings and the nature of the applied loads, many columns are subject to combined biaxial bending and axial load.

Seven …

Analysis And Tests [Of] L-Shaped Reinforced Concrete Column Under Combined Biaxial Bending And Axial Compression, Alaedin Majlesi

Theses

A total of five tests on biaxially loaded column specimens were conducted to investigate the complete behavior of load-deformation characteristics from zero load until failure. The specimens were tested under horizontal position with 60 ton hydrolic jack. Pin end was used for both ends to obtain higher accuracy of plotting curves.

Two specimens were tested with dial gages to obtain load-deflection curves and the other three specimens were tested with demec and strain gages to obtain load strain and moment-curvature curves. The strain gages were measured by weston bridge and deme-gages were measured by mechanical dial gage.

The above moment-curvature …

Failure Surface For L-Shaped Reinforced Concrete Short Columns, Mon-Chen Liu

Theses

Combined bending and axial compression for L-shaped reinforced concrete short columns is a common problem. But the present ACI Building Code (ACI 318-77), handbooks and texbooks pay no attention to this problem. A numerical analysis and computer program developed by Hsu fora reinforced concrete member subject to biaxial bending and axial load has been used Using this computer program, the interaction diagrams and failure surface were developed for L-shaped members under combined bending and axial compression. A comparison between theoretical and experimental results was included to examine the validity of failure surface.

Evaluating The Design And Operation Of Irrigation Canals In Egypt, Amany El Kayal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A computer simulation model for temperature data was developed in order to generate synthetic daily temperature. The model consists of two components: a deterministic component represented by a Fourier series fit, and a stochastic component represented by an autoregressive model. The simulation model was proven to be able to preserve the main statistics of the historical series.

The data generated by the above temperature model were used as an input to an irrigation water requirements simulation model. This model incorporates the probabilistic nature of these requirements. The irrigation system of Abo Raya area in Egypt was used to demonstrate the …

Nonpoint Source Pollution To Bear Lake, Utah-Idaho: Magnitude, Periodicity, And Watershed Management Alternatives, Victor J. Kollock

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

From April of 1981 to June of 1982 a Clean Lakes Program Phase 1 Diagnostic Feasibility Study was conducted on Bear Lake, a 282 km² (109m²) fresh-water lake located in southeastern Idaho and northeastern Utah. A portion of this Clean Lakes Program required an itemized inventory of all nonpoint sources affecting the lake's water quality.

A 16 month lake tributary monitoring program, which included the spring runoff periods of 1981 and 1982, provided data from which nutrient loading values (kg/day and kg/yr) were calculated. Analysis of these data, along with land use percentages within the Bear Lake …

Development Of A Computer-Aided Analysis Package For Linear Elastic Fracture Mechanics, William E. Warkentin

Theses and Dissertations

This thesis develops an interactive computer-aided analysis package for solving linear elastic fracture mechanics problems. CHILES 2 (an existing finite element fracture mechanics program) was modified to be interactive. The modified program is named CHILES.BYU and is used in conjunction with QMESH.BYU and MOVIE.BYU to form the total software package. An analysis of glass ceramics and glass ceramic/metal interfaces was performed demonstrating the capabilities of the package. This study demonstrates the usefulness of an interactive package of computer programs to allow an engineer to rapidly investigate different crack configurations.

Scrubs.Byu A Two Dimensional Finite Element Package For Continuum Analysis Using Quadratic Isoparametric Elements, Michael Glenn Long

Theses and Dissertations

This thesis develops a two dimensional, axisymmetric finite element package for solving continuum problems including rubbleization subsidence and nonlinear fracture mechanics. This package includes both a user friendly preprocessor, PRESCRUBS.BYU, and a versatile analysis code SCRUBS.BYU. PRESCRUBS.BYU systematically creates the data file necessary to run SCRUBS.BYU. SCRUBS.BYU provides many options of nonlinear static analysis using either linear or quadratic isoparametric finite elements. Sample problems are presented that demonstrate the capabilities of this package.

Analytical And Experimental Stresses In Concrete Pavements And Unbonded Overlays, Ahmad Jaber

Dissertations and Theses

The principal objective of this study is to determine the accuracy of calculating stresses in concrete pavements and unbonded overlays under different loading conditions. The computed stresses for the single layer pavements are obtained based on Westergaard theory, the finite-element model (ILLI-SLAB), and the elastic layered model (ELSYM5). For the two-layer unbonded systems, stresses are estimated based on the finite-element theory and the Portland Cement Association design method. The experimental results for the comparison were available from a series of tests done on model scale concrete pavements and unbonded overlays. The results of present investigation show that the computed stresses …

Secondary Stresses In Bowstring Timber Trusses, John F. Bradford

Dissertations and Theses

This study was undertaken in order to determine analytically the magnitude of the secondary (i.e., joint deflection induced) moments in the continuous glued-laminated chords of bowstring timber trusses. Traditionally, these moments have been assumed to be small and therefore neglected. The American Institute of Timber Construction makes no mention of these moments in their recommended design procedure.

A Study Of Single Angle Compression Members, James Robert Callaway

Dissertations and Theses

A study was undertaken to investigate the compressive capacity of a specific group of single angle members.

A review of existing literature and techniques was presented. Laboratory compression tests were performed on 22 angle members of four different sizes and two different lengths. Additional tests were performed to determine the yield strength of the material. The results, normalized with respect to the yield stress, were tabulated and discussed.

Two existing analytic models were used to attempt to predict the ultimate capacity of the test members. The first, an elastic method, was based upon the AISC combined stress equation. The second, …

Diseño Alcantarillado Barrio El Sociego Municipio De Madrid Cundinamarca, Mauricio Orlando Sanchez Sanchez, Rafael Eduardo Forero Villamil, Jorge Alberto Carrillo Garcia

Ingeniería Civil

No abstract provided.

Mechanical Properties Of High Strength Sheet Steels, M. Brad Parks

Masters Theses

"In recent years fuel economy has become one of the major criteria for the design of automobiles. In order to improve the efficiency of their vehicles many automotive designers are substituting high strength sheet steels for traditional materials of lower strength. This thesis discusses experimental work which was done to determine the representative mechanical properties and stress-strain relationships of a select group of high strength sheet steels with nominal yield strengths ranging from 80 to 140 ksi. The results show that high strength sheet steels are quite anisotropic with the variation in measured properties depending on the type of sheet …

Computer Usage In The Construction Industry And Construction Education, Stephen Douglas Stulken

Dissertations and Theses @ UNI

The rapid growth of computer usage in American society, and in the construction industry in particular, has important implications for construction education programs. There is a lack of current information about computer usage in the construction industry. Without this information, construction educators are less likely to provide students with relevant computer competencies that relate to the needs of the construction industry.

The objective of this study was to determine to what extent construction education programs provide the necessary computer competencies for their students. This was accomplished by comparing the current status of computer usage in the construction industry with computer-related …

Stability Analysis Of Closed Surge Tanks By Phase-Plane Method, Mostafa A. Sabbah

Civil & Environmental Engineering Theses & Dissertations

The governing equations describing water level oscillations in a closed surge tank with compressed air at the top of the tank are a set of nonlinear ordinary differential equations if the hydraulic system is analyzed as a lumped system. These oscillations are stable or unstable depending on the parameters of the plant and the type and magnitude of the disturbance.

The present available stability criterion has been developed by linearizing the governing equations and is, therefore, valid only for small disturbances.

In the research reported herein, the governing equations are normalized to reduce the number of parameters from nine to …