Computational Mechanics: Constitutive Modeling and Performance Analysis
The availability of supercomputers in the 80's has brought about a revolution in the analysis and design of complex structures. Parallel with this, computers have played a...

Optical Performance Predictions and Testing of a Composite Reflector
This paper describes the structural analysis and the experimental performance evaluation of advanced composite mirror designs for future NASA astrophysics missions. An interdisciplinary...

Structural Responses in Mechatronics
The design analysis of a circular cylinder, ring-stiffened intermittently, subject to conducting flow, is presented herein (Fan, 1986 & 1990). This composite cylinder is made of...

Thermal Effects in a Transient Study of Fracture
Studies, e.g. Zehnder and Rosakis (1989), indicate that fracture is associated with temperature rises in inelastic zones near the crack edge. To gain more insight into this phenomenon,...

Analysis of a CMC Compact Tension Specimen
A cohesive force model is applied to study the stability of fiber failure in a ceramic matrix composite compact tension specimen. By controlling the length of the bridged crack results...

Characterization of Acoustic Emission Signals
Separation of crack growth signals is of fundamental importance for detecting, locating and determining the significance of an internal flaw using acoustic emission techniques. An analytical...

Optimum Design of Laminated Metal Matrix Composites
With the increased demand for high-strength, lightweight materials that function successfully in high temperature environments, the effective development of metal matrix composites has...

The Application of Computerized Tomography for Determining Material Properties
X-ray computerized tomography (CT) is an imaging technique that has been used by the medical community for a number of years and is well documented. However, the adaption of this technique...

Cement and Concrete Characterization by Scanning Electron Microscopy
The scanning electron microscope (SEM) is a powerful tool for the microstructural and chemical characterization of cement and concrete. Imaging techniques such as secondary electron, backscattered...

Studies of the Interfacial Properties of Fiber Reinforced Cement
The multiple fiber pull-out tests were conducted with steel wires and alkali resistant glass fiber strand in order to characterize the behavior of interface of fiber and cementitious matrix....

Atomistic Simulation and Visualization of Thermal Disorder in a Crystalline Ice
The process of thermal disorder in crystalline ice has been simulated using a molecular dynamics model. The thermal disorder is induced by raising the temperature of the system. The molecular...

Mechanical Behavior of Composites with Interphases
The effect of interphases on the mechanical behavior of fiber-reinforced composites is studied. Two problems, a cracked fiber in a matrix, and a fiber pulled out of a matrix, are discussed....

Theoretical and Experimental Mechanisms of Toughening in Multi-phase Materials
Multi-phase materials are an important class of materials being developed for aerospace primary structural applications. Multi-phase materials are those materials consisting of two or...

Nonlocality of Continuum Approximation of Microcracked Materials
A continuum with nonlocal damage has recently been shown to be an effective approach for the analysis of strain-softening structures. The basic idea is that only the damage, normally caused...

A Phenomenological Approach to Physico Chemical Phenomena Coupled with Damage in Massive Concrete
This paper presents the first experiments which have been done to support the bases of a thermomechanical model coupled with damage and to identify the characteristics parameters needed...

Instability and Plastic Flow of Soils
Materials should according to Drucker's postulate become unstable when the second increment of plastic work is negative. Experimental observations however show otherwise....

Modeling of Successive Impacts in Sand
The principal aspects of numerical modeling of successive, high energy impacts in sand are discussed in this paper. These include the numerical formulation used for solution of the equations...

Comparison of a Microscopic Model and a Macroscopic Model Predictions on the Stress-Strain Behavior of a Soil
The stress-strain behavior of a soil under drained triaxial conditions was simulated using the Microscopic constitutive model TRUBAL. The model parameters for the Macroscopic constitutive...

Constitutive Relations for Granular Solids Accounting for Heterogeneous Deformation Fields
Under high deviatoric stress levels corresponding to large strains, the deformation of granular media is highly heterogeneous. A micro-mechanical approach is developed here to model the...

A Time-Dependent Microplane Model for Creep of Cohesive Soils
The microplane model is used in this paper to describe the time-dependent (creep) behavior of cohesive soils (clays). The constitutive equations are defined on each of a set of microplanes...

 

 

 

 

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