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Introduction While the unique physical and mechanical properties of loess making it have a greater change in strength and deformation after soaking, this have a greater influence on the stability and security of underground structures.
Coupled with complex topography, hydrogeology, climate and other conditions of the loess regions, these factors make a great security threat to loess tunnel stability, even operated for several years ,parts of tunnels appear serious disease, such as lining split, tunnel leakage, basement subsidence and floor heave[1~2].
Xi'an is located in the warm temperate semi-humid monsoon climate zone with more seasonal rainfall, and follow the increase in sudden severe weather recent years，these aggravate urban water accumulation in the rainy season, loess surrounding rock soaking will affect the tunnel lining system.
Finite Element Calculation Model According to the engineering geological conditions and the mechanical properties of surrounding rock, we adopt the plane elastic-plastic finite element method and D-P yield criterion for the simulation.

Contact Damage in Brittle Curved Coatings: The Influence of Indenter/Coating Modulus Mismatches Tarek Qasim, Chris Ford, Mark Bush, Xiao-Zhi Hu School of Mechanical Engineering, the University of Western Australia, 35 Stirling Highway Crawley W.A. 6009, Australia a tqasim@mech.uwa.edu.au, b chrisf@mech.uwa.edu.au, cmark.bush@uwa.edu.au, d xhu@mech.uwa.edu.au Keywords: Margin damage, Curved surfaces, Radial cracks, Crown failure.
The combination of a hard, brittle outer layer and a compliant, tough inner layer offers high wear resistance and damage tolerance, factors that are crucial to the lifetime of such structures.
These studies have enabled the determination for various damage modes of the dependencies of critical loads on geometrical variables such as coating thickness, indenter radius and sample radius, as well as on material properties such as interlayer elastic modulus mismatch.
Critical loads PR to initiate the radial cracks are significantly affected by the indenter modulus (Fig. 4).
All damage modes should be evaluated, as well as geometrical variables and materials properties.

The mechanical properties of hydrogels are important design parameters in tissue engineering, as the gel must create and maintain a space for tissue development.
In addition, the adhesion and gene expression of cells are tightly related to the mechanical properties of the polymer scaffold [2].
Hydrogels designed for tissue engineering scaffolds may contain pores large enough to accommodate living cells releasing growth factors and creating pores into which living cells may penetrate and proliferate [3].
The seeding and proliferation efficiency were affected by the pore size of the scaffolds.

It was affected by tensile strength therefore local effect has not found spalling in crater field.
Characterization porous such as volume, size, spacing and pore size distribution is primary factor to influence material properties of FC mainly on density and strength.
Experimental 3.1 Material Properties In this investigation pre-foaming method were applied to develop target specimens.
Conclusion Mechanical anchoring occurs when the PF and concrete matrix interlocking.
Ashby, Cellular Solids Structure and Properties, Cambridge University Press, (1997), in press

The paraffin which coats the copper granules can change the structural properties, reduce strength and hardness, and diminish the surface force of copper granules, causing the increase of depolymerization effect and contrarily the decrease of conglobation effect.
The possible reasons are analyzed as follows: on the microscopic level, during milling process, repeated mechanical deformation may have induced many dislocations.
The face-centered cubic copper with a good plastic property is easy to deform and produces a large number of dislocations in a short time, leading to the refinement of crystal grains and the very close approach to the limit of energy conversion.
Table 1 Elongation of Thermal Expansion of Composites at 50℃ [mm] Milling Time / h Heating Time / s 20 30 40 50 20 0.92 1.13 1.29 1.39 50 1.04 1.18 1.35 1.42 80 1.14 1.28 1.41 1.42 Fig.4 Thermal sensitivity of composites with different milling time Because the difference in thermal sensitivity of composites is directly related to the coefficient of thermal conductivity, the factors affecting the thermal conductivity is discussed to explore the relationship between milling time and thermal sensitivity.

As a result the development of heavy forging field is one the factors representing the level of nation’s industry and national defense.
It is difficult to forge titanium alloy, because of narrow forging temperature and large shape-changing resistance of titanium alloy, it would cause easily non-uniform tissue and unstable property, even cracking.
From the aspects of forging strain, damage factor and required loading we compared how different fillet radius of V-shaped anvil edge influence on forging quality.
Furthermore, we also report here how fillet radius of V-shaped anvil edge affect forging quality on different diameters of heavy long-axis forgings in squaring process.
The damage factor is the minimum for Φ600mm axis ingots and V-shaped anvil fillet radius 100mm, for Φ1000mm and Φ1200mm ingots with 50mm anvil fillet radius.

In order to achieve a scientific selection of fly ash used in concrete, the influences of fly ash level on cementitious system rheological parameters, hydration degree and capillary adsorption properties were quantitative analyzed.
The influences of fly ash on concrete macro properties such as workability, mechanics property and durability were mainly inspected when different levels of fly ash were used in practical engineering [2].
The fly ash level was set to be the only variable parameter in concrete mix proportions to exclude impacts of other factors on test results.
The final test results were recorded and the appropriate fluid models were selected to fit and to obtain the paste rheological properties parameters including yield stress and plastic viscosity.
In-depth analysis found that the fly ash level also affected the hydration products increase rate.

Introduction Controlled non-homogeneity of the structure by powder metallurgy processes makes it possible to obtain special properties of materials, which cannot be obtained by conventional technologies [1].
In particular the porosity is beneficial to the sliding bearings, which decides their mechanical properties to a greater extent than any other microstructural factor (grain size, dislocation nature, texture) [4].
Isolated porosity controls the formation of different types of fracture facets related to geometry and properties of particle necks.
Zakharova, Mechanical properties of sintered materials.
Upadhyaya, Densification, microstructure and properties of supersolidus liquid phase sintered 6711Al-SiC metal matrix composites, Sci Sinter, 42 (2011) 363

The other factors that greatly affect the selection of building materials are · thermal comfort, · good mechanical properties (strength and durability), · aesthetic characteristics and · ability to construct quickly.
However, it is also important for sustainable development to consider social and economic factors as well.
· Concrete is a durable material with excellent mechanical properties.
The use of admixtures—materials added to concrete—becomes very popular as the final composite can have better durability and gains some specific unique properties.
HPC is a type of concrete that has a low water- cement ratio, properties of which are improved by the use of super-plasticizers

Studies on Galling Behavior in Square Cup Drawing of High Tensile Strength Steel Lin Qi-quan1, a, Dong Wen-zheng1,b , Wang Zhi-gang2,c 1School of Mechanical Engineering, Xiangtan University, Hunan, Xiangtan,411105,China 2Department of Mechanical Engineering, Gifu University, Gifu 501-1193, Japan axtulqq@126.com, bxtu_wenzheng@163.com, czgwang@cc.gifu-u.ac.jp Keywords: High Tensile Strength Steel; Galling; drawing; DEFORM-3D; Coating Abstract: In this study, galling behavior in macro-scale is investigated in the square cup drawing of a high tensile strength steel in semi-dry and dry condition on laboratory experiments.
From the galling trace in Fig. 2, the galling seems to occur while the drawn cup is sliding after the top edge has passed through the die shoulder, and the sliding distance is possibly a dominant factor in galling.
Its properties including tensile strength and elongation, etc., as shown in Table 1, specifically the friction coefficient of workpiece-die and workpiece-punch were 0.1 and 0.12, respectively. 3.1 Comparing the drawing force between experiment and FEM simulation Fig. 7 shows the drawing force between experiment and FEM simulation.
Additional experiments with coated dies As we discussed above, the die life was seriously affected by the galling occurring on the non-coated dies, consequently, the experiments for TiC (CVD) and DLC-Si (DC -PACVD) were continued with the experimental conditions in Table 2.
Hirose:Transactions of the Japan Society of Mechanical Engineers Ser.