Dynamic Effect of Sediment on Dam Hydrodynamics
The dynamic behavior of reservoir sediment during earthquakes is important to an analysis of dam safety when the depth of the water is seriously reduced by the sediment. While the dynamic...
Direct Tensile Test: Stability and Bifurcation
Unnotched specimens of quasibrittle materials that exhibit post-peak strain softening do not deform symmetrically in a direct tension test. The phenomenon (which is similar to the recently...
Two-Dimensional Statistical Micromechanical Models for Microcracked Brittle Solids
Recent development undertaken by the authors in two-dimensional statistical micromechanical models for brittle solids with randomly located interacting microcracks is presented. Overall...
The Initiation of Bifurcations and Localization in Damaging Materials
Criteria for diffuse and discontinuous bifurcations have previously been developed and used to investigate the initiation of necking and localization in elastic-plastic materials. In this...
Softening Models for Concrete: Stability and Uniqueness
A microstructurally-based, numerically oriented, fracture-induced softening model for concrete is presented. Rate-dependent evolution equations for microcrack nucleation, growth, and coalescence...
Damage Mechanics Modeling of the Cyclic Behavior of Plain Concrete
The sudden stiffening behavior of concrete under cyclic loading is discussed and the available experimental investigations to delocalize damage is reviewed. A discussion on the applicability...
Determination of In-Situ Stresses From Acoustic Emissions
Acoustic emissions (AE) are microseismic activities that are generated in concrete by cracking and damage. The rate of Acoustic Emissions, called the 'Event Rate', can provide indication...
Evaluating Polymer Concrete Bridge Expansion Joints Using Acoustic Emission
This study is to simulate the acoustic emission (A/E) of polymer concrete bridge expansion joints subjected to controlled representative loads by a rotating test apparatus on a circular...
Detection of Cracks in Reinforced Concrete Cans
The Acoustic Emission Technique (AET) is known as a good possibility for non destructive detection of cracks in metal down to very small dimensions. To use AET for concrete, an efficient...
On the Modelling of Damage Due to Volumic Variations in Cementitious Composites
Two kinds of volumic variations are considered. Those due to thermal gradients on hardened concrete and those due to hydration processes at early ages. Models based on damage mechanics...
Strain-Based Damage Deactivation in Concrete
Motivated by the 'mode I' microcrack opening and closing mechanism, a procedure for the deactivation of the damage is developed. Strain based projection operators are used to negate the...
Contact Induced Damage
Contact induced damage is an important source of potential failure of engineering components. The particular applications where this damage occurs are in the automotive, aerospace and...
Evolution of Damage in Brazilian Test Using Holographic Interferometry
A common method for estimating the tensile strength of concrete is the Brazilian Test. The test is carried out by loading a cylinder on its side in diametral compression. Accodring to...
The Microstructure of Hardened Cement Paste and Concrete
Concrete is a composite material created from a mixture of a binder (hardened portland cement paste) and a filler (fine and coarse aggregates). Like any other composite material the physical...
Computational Framework for 3D Nonlinear Discrete Crack Analysis
Under contract from the Electric Power Research Institute (EPRI) to investigate the applicability of fracture mechanics to concrete dams, the authors are involved in the development of...
Shear Resistance Models for Concrete Bridges
Statistical models are developed for the shear resistance of concrete bridge girders. Two structural types are considered: reinforced concrete T-beams and prestressed concrete AASHTO girders....
An Elastoviscoplastic Model for High Strength Concrete
An elastoviscoplastic model of overstress type is proposed for high-strength concrete in this study. With its viscosity parameters determined with experimental data from the split-Hopkinson-pressure-bar...
Mechanical Properties of High Performance Concretes
This paper presents some of the initial results of a 4-year research project on mechanical properties of high performance concretes with particular reference to highway applications. High...
Fiber Suppressed Localization in Tension
Tensile fracture in portland cement based fiber composites is studied. Formation and propagation of stable microcracks is examined by means of holographic interferometry. Distributed microcracking...
Scattering of Waves by Steel Reinforcement in Concrete
The application of wave-sensing methods to the non-destructive evaluation of concrete structures requires often the use of simple (or at least tractable) models for the solution of the...
Return to search