Results 171 to 180 of about 408,531 (212)

Modeling Drying Shrinkage Stress Gradients in Concrete

Cement, Concrete, and Aggregates, 2004
Abstract The potential for drying shrinkage cracking in concrete is related, in part, to the development of a moisture gradient across the cross-section of the concrete element. A model has been developed that incorporates experimental measurements of internal relative humidity to investigate drying shrinkage stress gradients in concrete
ZC Grasley, DA Lange
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Stress and strain during supercritical drying

Journal of Sol-Gel Science and Technology, 2018
Supercritical drying avoids capillary forces, but damaging stresses can be generated during solvent exchange, pressurization, and depressurization. Each of those steps has been analyzed, so the duration of the process can be minimized without risk to the sample.
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Stress formation during heating in supercritical drying

Journal of Non-Crystalline Solids, 2001
Silica aerogel preparation is analyzed and two different supercritical drying techniques, autoclave drying of the solvent and drying following carbon dioxide exchange of the solvent, are compared in terms of stress formation during the heating step. The model used is a partial differential equation that relates stress to thermal expansion and flow of ...
Betul Unlusu, Sermin G. Sunol, Aydin K. Sunol   +2 more
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Drying Induced Stresses in Viscoelastic Sphere

2001
The main subject of this paper is to study how the constitutive model of saturated porous body influences the numerically estimated drying induced stresses and deformations. Mechanical properties of porous materials are changing during drying. At the beginning they are viscous and in the course of moisture removing become viscoelastic, elastic or even ...
J. Banaszak, S. J. Kowalski
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Drying-Induced Strain and Stress: A Review

Drying Technology, 1996
ABSTRACT This paper is to review the works on strains and suesses in materials during drying.The strains and suesses are caused when temperature and moisture gradients are generated in mterials whose volume changes with heating and moisture removal. In such materials. failure and irregular deformion may be generated which affect considerably the qudity
Masanobu Hasalani, Yoshinori Itaya
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Thermal stress analysis of dry friction clutches

Industrial Lubrication and Tribology, 2018
Purpose The purpose of this paper is to present an approach to compute accurately the distributions of the frictional heat generated, contact pressure and thermal stresses at any instant during the sliding period (heating phase) of the single-disc friction clutch system works in the dry condition and the complex interaction among them.
Kaleli, Hakan, Jobair, Hussein, Schlattmann, Josef, Abdullah, Oday Ibraheem, Beliardouh, Nasser Eddine   +4 more
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Drying shrinkage and stresses

1992
A numerical study of the effects of shrinkage and stresses on drying kinetics was performed. A diffusional model was used, taking into account the deformation of the solid. The materials studied were a medium-shrinkage clay and a highly shrinking gel.
Ketelaars, A.A.J., Jomaa, W., Puiggali, J.R., Coumans, W.J.   +3 more
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Stress development in drying coatings after solidification

AIChE Journal, 2002
AbstractAs a coating solidifies by drying, it tends to shrink. It is liquid enough in early stages that any shrinkage stress is rapidly relieved by viscous flow. It becomes solid enough in later stages to support elastic stress, which results from shrinkage inhibited by adherence to the substrate. Stress can relax by viscous creep in the coating. Thus,
H. Lei, L. F. Francis, W. W. Gerberich, L. E. Scriven   +3 more
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A Stress Model for Lumber Drying Control

Journal of Dynamic Systems, Measurement, and Control, 1982
Rapid changes in lumber value and energy costs have forced concern for more efficient lumber drying and a higher quality end product. Computer automation provides a practical solution to this problem. Mathematical predictions of moisture loss and shrinkage induced stress are required for effective automation. In response to this need an elastic-plastic
R. A. Lessard, D. E. Limbert, J. L. Pokoski, J. L. Hill   +3 more
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Stresses Generated During Convective and Microwave Drying

Drying Technology, 2005
An outline of the mechanistic model of convective and microwave drying of saturated capillary-porous materials is presented. The model was derived in the framework of irreversible thermodynamics. Particular attention is devoted to construction of the term describing the power of microwave radiation absorbed per unit volume, which is converted into ...
Stefan J. Kowalski, Kinga Rajewska, Andrzej Rybicki   +2 more
openaire   +1 more source