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Against the background of shenyang subway shield tunnel construction, the method of numerical simulation methods are used to analyze the factors of surface subsidence caused by shield construction comprehensively, and the universal finite element program ABAQUS is used to establish mechanical model depended on comprehensive consideration the influence factors of soil warehouses pressure, seepage and groundwater.
The shield construction methods of surface subsidence are caused by many factors, and it has been discussed by many literatures [1].
On the one hand, when tunnel are excavated below the groundwater level, groundwater flows into the work face, and produce dynamic and static water pressure caused by groundwater, which change the physical and mechanical properties of rock mass, and change its stress state.
In establishing calculation model, in order to exclude the influences of other factors, assume other factors are invariable.
After consideration the influence of surface subsidence in the three kinds of factors above comprehensive, the surface settlement distribution cloud image shown in Fig. 6.

It is insufficient only to carry out mechanical property of rod-shaped samples.
The decrease in workability adversely affects the overall component cost and the ability to achieve the desired properties.
Because the developments of P/M superalloy are followed as the utilization of turbine engine disc, the related studies are investigated in terms of low cycle fatigue, fatigue crack propagation, thermo-mechanical fatigue, creep strength, burst and tensile properties [1-8], but few papers were published discussing the high cycle fatigue of P/M superalloy.
The effects of surface factors would decrease at high stress state.
Besides peening effect, there are not other main influence factors on initiation site.

Initial imperfections on beam string structure (BSS) include geometric imperfections and residual stresses, which negatively influence the mechanical properties of BSS.
This paper analyzed the mechanical influences of initial imperfections on BSS by FEA, pointed out that initial imperfections do not remarkably influence the properties of BSS in stage of prestressing, but geometric imperfections obviously influence the displacement out of plane in stage of use, which should be controlled to improve the safety of BSS by installing enough lateral supports at the upper chords of BSS in construction.
Introduction The imperfections in beam string structure mainly include geometric imperfections and residual stresses, which negatively influence the mechanical properties of BSS according to general principles of steel structures [1], but researches about the problem are very scarce because of complexity of initial imperfections and high cost of analysis.
On this condition, designers generally neglect the negative influences of initial imperfections and simply leave some margin for their design to treat with the problem, which probably hides some dangerous factors in structure.
The fact of limited plastic development determines that the decrease of stiffness of BSS coming from plastic factor is not apparent so that the whole mechanic properties of BSS are not affected obviously.

Study on Mechanical Properties of a Through Tied Arch Bridge Model with Different Wind Bracing Forms Shengkui Dia, Fuzhou Baib, Aili Zhangc, and Hui Lid School of Civil Engineering, Lanzhou University of Technology(LUT), Lanzhou, Gansu, 730050, China adisk@lut.cn, bbaifuzhou800@163.com, caili696@163.com, dlih@lut.cn Keywords: Through Tied Arch Bridge; The Form Of Wind Bracing; Static Characteristic; Dynamic Characteristic; Stability.
This article will adopt the methods of numerical simulation and experiment to study the effects of the tie arch bridge’s mechanical properties under the several common wind bracing .
The main features are: (1) Research the layout of wind bracing to the mechanical properties of tied arch bridge; (2)Produce the experimental models, and study the dynamic characteristics by experimental method; (3)Analyze the static response of the bridge under the wind loads with different wind bracing.
Fig. 1: Model and additional bob-weight In order to study the effect of the form about wind bracing to the various mechanical properties of the `structure, some steel sheets were reserved on the arch rib when the model was produced, which has bolt holes, and various type of wind bracing have been produced in advance, which guarantee that the wind bracing can be replaced at any time.
Conclusions Through two methods, include the numerical simulation and experiment, the research on mechanical properties of through tied arch bridge under different wind bracing forms, some conclusions can be found as follows: l For the through tied arch bridge, layout of wind bracing is necessary, wind bracing can improve the overall stiffness and stability of the bridge, especially in vertical, but it has little effect to the transverse stiffness and stability.

These affect the mechanical property of the kenaf sandwich panel, which also explains the deviation of flexural property during testing [3].
Fibers having high aspect ratio are good for fiber bonding and entanglement giving better mechanical properties that are required in natural fiber composites [7].
Aspect ratio is also one of the factors that influence the quality of interfacial bonding between matrix and reinforcement that will affect the mechanical properties of the composites structures.
From observation, due to kenaf dispersion not evenly distributed in matrix, affect the mechanical property of kenaf during testing.
Interfacial Effect on the Mechanical Properties of Glass/Phenolic Composite, Shonan Institute of Technology, Japan

Several I-shaped steel beams reinforced by CFRP are unloaded at different levels and the mechanical properties are analyzed and compared.
Many factors should be taken into consideration for structural reinforcement.
Therefore, steel properties of both elastic stage and are set.
Only elastic modulus and Poisson’s ratio are needed for elastic material properties, while plastic properties are reflected through the definition of the true stress and plastic strain of I-shaped steel beam (Fig. 2).
Plastic material properties of I-shaped steel beam are not included in table 1.

As a consequence they may also affect the metallurgical properties.
Traditionally, TPM has been conducted with a view to optimising the products final metallurgical and mechanical properties.
As a consequence they may also affect the metallurgical properties.
The empirical factor a, determined to a value of 0.11, contains specific properties such as mill design, lubricant, work roll surface, alloy, etc..
Both factors increase friction.

Based on the structural characters of roof in fully mechanized top coal caving, mechanical analysis, mechanical calculation and simulation experiment were used to explore the particularity of roof structure in fully mechanized top coal caving.
Comparing with the general fully mechanized mining, the top coal caving has two different basic factors, mining height and the properties of roof.
The change of mining height directly affects the height of caving zone, and the change of roof’s properties affect the transfer mode form overlying strata structure to support’s force.
In this paper, the change and change form of overlying strata structure, determining working characteristics and reasonable support resistance of hydraulic supporting frame, and the relationship between these factors, parameters and properties of mining height and roof were systematically analyzed in the condition of fully mechanized top coal caving.
However, because of the change of mining height and roof properties, it is obvious that the support pressures were difference between the fully mechanized top coal caving and general fully mechanized mining.

For identifying the significant factors that affected the deposition yield, multivariate analysis of variance (MANOVA) and regression analysis based on partial least-square method were used.
HNT incorporation in polymer films has been shown to improve mechanical properties of functional films [8-10].
Titanium dioxide (TiO2) is used for coatings of metal implants because it presents antibacterial properties [1, 12, 13] as well as high biocompatibility [13-15].
Duarte, Structural, Electronic, and Mechanical Properties of Single-Walled Halloysite Nanotube Models, J.
Kawashita, Novel bioactive materials with different mechanical properties, Biomaterials 24 (3) (2003) 2161-2175

Empirical equation of thermal conductivity is obtained and conductivity factor is ensured by test data.
Zhao Jian conducted an experimental study of hydro-thermal properties of rock fractures by heating the rock and forcing the water circulation through the rock fractures[5].
In this paper, by testing thermal conductivity, conductivity factor is ensured for fracture rock.
Thermal Conductivity Test This test’s purpose is determining conductivity factor of rock.
(3) The water in the fracture is laminar, and physical properties is constant.