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Taking some deep buried immerse tunnel as the background, the paper discussed the deformation characteristics of gravel bed by physical model experiments to get the settlement and compression modulus, appraised the impact of factors over deformable characteristic.
The test load is applied step by step according to the design load by the loading system, and data such as gravel top settlement, pile stress, gravel pressure data etc are recorded by measurement system to calculate compression modulus, resilient modulus of the gravel bed, and to evaluate the impact of various factors on mechanical properties of the gravel bed.
Reasonable gravel non-uniformity coefficient and curvature coefficient are beneficial to improve the gravel modulus, but a continuous gradation will reduce the gravel porosity, and affect its capacity to accept silt; B2 particle size shows the best mechanical properties, compression modulus of 8.55MPa, high porosity, which were used as final selected gradation.
Gravel crushing will affect the performance and durability of the foundation and bring the project risk.
When selecting gravel gradation, it should also consider the compression modulus, porosity, particle size and other factors

The main reasons for that process are supplement corrosion factors such as a wide range of temperature, humidity as well as chemical agents in the environment.
In this article results of different properties (mechanical, electrical) of electrically conductive concrete are discussed including their alterations due to sulphate attack.
Scheme used to measure electrical properties 2.
Study of electrical properties.
It was found that significant absorption of sulfates is accompanied by a loss of physical and mechanical properties due to the formation of pores and voids.

Several factors associated with the restorations’ surface quality are surface roughness, wear resistance, and mechanical properties [6, 19].
Among these properties, surface roughness has a major impact on the biofilm adhesion and maturation.
Beside arising from physiological factors and patient habits [8, 23].
Wear is the common mechanically factors of degradation dental resin composite.
Martin, Surface properties of resin composite materials relative to biofilm formation, Dent Mater J 26(5) (2007) 613-622

Abstract:- Surface mechanical attrition treatment (SMAT) technique became popular to develop a nanostructured surface layer on metallic materials for upgrading their overall properties and performance.
Introduction Nanocrystalline materials have improved properties, like wear resistance, yield strength, hardness.
Nanocrystalline surface layer can enhance the physical and chemical properties of the components.
Enhanced physical and chemical properties are the results of this gradient microstructure of SMATed cross-sectional surface.
SMAT can be the remedy to enhance their properties.

The surface modification of carbon nanotubes (CNTs) has been recently observed to influence the distribution of CNTs in epoxy resin and the mechanical properties and electrical conductivities of these CNTs.
This investigation studies the consequent enhancement of the mechanical properties and electrical conductivities of CNTs.
Additionally, all of these factors critically affect the creep behavior and the strength of composites.
Hadjiev,“A strategy for improving mechanical properties of a fiber reinforced epoxy composite using functionalized carbon nanotubes,”Composites Science and Technology, vol. 71,(2011), pp.1089-1097 [12] T.
Shimamura,“Mechanical properties of alighed multi-walled carbon nanotube/epoxy composites processed using a hot-melt prepreg method, ”Composites Science and Technology.(2011) [13] Chen, C.

When inserted, these blocks will be affected by a scale factor according to their intended size.
Treating this representation as a regular block does not give any results, while the insertion scale factors cannot follow the actual variation of dimensions.
The radial ball bearing dynamic block (a) and the corresponding Block Properties Table (b) The Parameters Manager lists dimensional constraint parameters, reference parameters, and user parameters [9].
The Block Properties table defines and control values for parameters and properties within a block definition, Fig. 8.b.
When selecting the block reference, the drop-down menu is set to the values defined by the row Reference in the block properties table, Fig. 8.a.

An analysis making it possible to evaluate the effect of the factors affecting the performance of the long-term cable constitutes the principal work in our lab.
Their mechanical properties change during their uses.
The damage by tiredness is described by the deterioration of the mechanical properties of material following cyclic requests.
The various theories representative of this damage is unified theory [5, 9]:  The request of a material in fatigue generally induces a degradation of its physical properties.  
This function of distribution has the following properties: F (-∞) = 0; F (+∞) =1.

The formation of intermetallic compounds in brazed joints between SUS304 and nickel-based filler metal is a major concern, since they considerably degrade the mechanical properties of joints.
The results showed that, the mechanical properties of brazing layer could be stabilized through increasing the brazing temperature over 100° C more than melting temperature of filler metal, and increasing the brazing time over 120min. long, and diffusing enough the intermetallic compounds formed in the brazing layer to the base metal.
In the present study, in order to obtain high brazing strength of stainless steel and undertaken to investigate the properties and microstructure of SUS304/BNi-2 filler metal brazed systems, and the influence of brazing parameters on the maximum joint strength.
Brazed joint properties were evaluated at room temperature and using tensile test.
The mechanical properties of brazing layer could be stabilized through increasing the brazing temperature over 100°C more than temperature of filler metals, and increasing the brazing time 120min. long, and diffusing enough the brittle intermetallic compound formed in the brazing layer to the base metal.

The other group of possible mechanism relates the degradation of the mechanical property of a Cr2O3 scale [14-18].
That is, invasion of water vapor into the substrate is caused by deterioration of the mechanical property of the Cr2O3 scale accompanying the generation of cracks, which is due to dissolution of hydrogen into the Cr2O3 scale or to an originally brittle property of it.
In addition, we discussed change in a mechanical property of Cr2O3 scales formed in H2O-containing atmospheres.
Based on the above results, it may not be adequate that hydrogen dissolved into a Cr2O3 scale results in degradation of the mechanical properties of the Cr2O3 scale.
Based on the above discussion, it could not say that the dissolved hydrogen in Cr2O3 scale degrades the mechanical property of a Cr2O3 scale.

In the stage of nugget growth and mechanical collapse, the growth of the molten nugget and mechanical collapse continue to cause resistance to decrease beyond the peak.
The discrepancy cause the force from the liquid nugget (due to the internal pressure in a liquid expansion and other factors) exceed than the effective electrode force that is a portion of the electrode force.
Although surface expulsion may not affect the strength of the joint if it is limited to the surface, it severely affects surface quality and electrode life.
The risk of expulsion is especially high in resistance spot welding between aluminum alloy and steel because of the very dynamic and unstable characters of the process, which is related to the application of a high current in a short welding time, and the intrinsic electrical, thermal, metallurgical and mechanical properties of aluminum alloy.
References [1] RF Qiu, S Satonaka, C Iwamoto, Mechanical properties and microstructures of magnesium alloy AZ31B joint fabricated by resistance spot welding with cover plates, Science and Technology of Welding and Joining. 14(2009) 691-697