Doctoral Dissertations

Abstract

"Stress wave propagation and interaction in plain concrete leading up to spall fracture was investigated experimentally with a computer numerical analysis of the bar-geometry axial-impact loading. The critical normal fracture strain energy U and mechanical energy W criteria are proposed for the spatial and time dependence explanation of spallation in concrete. The energy criteria are special cases of a more generalized cumulative damage model of the form:....

Finite-difference analyses of the wave propagation and interactions in the split Hopkinson bar showed that early failure in brittle materials limits the application of the conventional method of analysis because equilibrium in the specimen is not reached before failure. The dynamic stress-strain-strain rate curves indicate that the failure strain is more a function of strain rate than is the ultimate stress, the latter case being observed by other investigators. Dynamic unloading stress-strain curves in the post-failure region are shown to be generally similar to those obtained by servo-controlled testing machines at lower strain rates"--Abstract, page ii.

Advisor(s)

Haas, Charles J.

Committee Member(s)

Rollins, Ronald R.
Clark, George Bromley, 1912-
Foster, J. Earl
Pyron, Howard D.
Spokes, Ernest M., 1916-1995

Department(s)

Mining and Nuclear Engineering

Degree Name

Ph. D. in Mining Engineering

Sponsor(s)

United States. Department of Defense

Publisher

University of Missouri--Rolla

Publication Date

1972

Pagination

xiii, 140 pages

Note about bibliography

Includes bibliographical references (pages 89-91).

Rights

© 1972 Esteban Eulogio Miranda, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Library of Congress Subject Headings

Concrete -- Fracture -- Mathematical models
Deformations (Mechanics)
Stress-strain curves -- Mathematical models

Thesis Number

T 2795

Print OCLC #

6037346

Electronic OCLC #

904616802

Comments

Financial support was provided by the U. S. Department of Defense, THEMIS Contract No. DACA-45-69-C-0087.

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