Mechanical Damage Characteristics of Red Sandstone Under Triaxial Cyclic Loading

Laser-induced thermal–mechanical damage characteristics of window materials are the focus problems in laser weapon and anti-radiation reinforcement technology. Thermal–mechanical effects and damage characteristics are investigated for cleartran multispectral zinc sulfide ( ZnS ) thin film window materials irradiated by continuous laser using three-dimensional (3D) thermal–mechanical model. Some temperature-dependent parameters are introduced into the model. The temporal-spatial distributions of temperature and thermal stress are exhibited. The damage mechanism is analyzed. The influences of temperature effect of material parameters and laser intensity on the development of thermal stress and the damage characteristics are examined. The results show, the von Mises equivalent stress along the thickness direction is fluctuant, which originates from the transformation of principal stresses from compressive stress to tensile stress with the increase of depth from irradiated surface. The damage originates from the thermal stress but not the melting. The thermal stress is increased and the damage is accelerated by introducing the temperature effect of parameters or the increasing laser intensity.

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Study on the Engineering Properties of Saturated Red Sandstone

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.638-640.589 ◽

2014 ◽

Vol 638-640 ◽

pp. 589-593

Author(s):

Hong Yi Wang ◽

Wu Xiu Ding ◽

Jin Jin Yang

Keyword(s):

Construction Projects ◽

Elasticity Modulus ◽

Triaxial Compression ◽

Mechanical Damage ◽

Confining Pressure ◽

Peak Strength ◽

Engineering Properties ◽

Compression Tests ◽

Red Sandstone ◽

Slope Excavation

Red sandstone with a strong water softening can cause difficulties of construction projects, especially for slope excavation and support engineering. Therefore, the study on the engineering properties of saturated red sandstone has a important meaning. The mechanical parameters of saturated red sandstone are obtained by the triaxial compression tests. The test results indicate that the ralations between peak strength, elasticity modulus and confining pressure for the saturated specimens are similar with the natural specimens, that is, with the increasing of confining pressure, the peak strength and the elasticity modulus will increase, but the growth rate becomes slowly. Under the same confining pressure, the peak strength and the elasticity modulus of saturated specimen are more smaller than the natural one. The mechanical damage caused by water recedes when the confining pressure increases, so for the geotechnical engineering with larger influence of water, the increasement of confining pressure by the supporting structures is conducive to the stability of rock mass. The research results will provide a theoretical basis for the red sandstone engineering.

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Damage characteristics of sandstone subjected to pre-peak and post-peak cyclic loading

Acta Geodynamica et Geomaterialia ◽

10.13168/agg.2019.0011 ◽

2019 ◽

pp. 143-150 ◽

Cited By ~ 4

Author(s):

Yubao Zhang

Keyword(s):

Cyclic Loading ◽

Damage Characteristics

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Mechanical Damage to the Intervertebral Disc Annulus Fibrosus Subjected to Cyclic Tensile Loading

Advances in Bioengineering ◽

10.1115/imece2003-43302 ◽

2003 ◽

Author(s):

David A. Ryan ◽

Jeffrey J. MacLean ◽

James C. Iatridis

Keyword(s):

Cyclic Loading ◽

Material Properties ◽

Annulus Fibrosus ◽

Permanent Deformation ◽

Mechanical Damage ◽

Quantitative Relationship ◽

Peak Stress ◽

Tensile Loading ◽

Number Of Cycles

Damage progression in the circumferential direction of the disc annulus is likely to occur in vivo in response to cyclic loading with associated degradation in tensile material properties, yet this information is not available in the literature. We hypothesize that damage of the annulus will be increased by the number of cycles and magnitude of strain applied to the tissue. Therefore, the objective of this study is to obtain a quantitative relationship between number of cycles and magnitude of tensile strain and damage on the annulus fibrosus. Damage to the annulus is assessed through measurement of permanent deformation (% elongation) and peak stress in the tissue under cyclic loading conditions.

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