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With the affect of overlapping dynamic and static stress field, the calculation formula of the critical inner water pressure in water inflow was presented.
And the blasting disturbance would enhance the stress intensity factor of crack tip.
At the moment, fracture was affected by three loads: blasting load, in-situ stress, and high water pressure.
According to Type (10), and the mechanical properties of water fractural rock mass in Xiamen Xiangan subsea tunnel, parameter values were settled as follows: in-situ stress =0.875Mpa（thickness of the overburden was 34m）, side pressure coefficient was 0.7, and =0.4375MPa; poison radio was 0.4 (according to Table 1, =0.943，)；length of fracture named a was 0.1m; internal friction angle of fracture named was 30°; attenuation coefficient of stress wave was 1.636 [1]; charge diameter was 0.021m (fully coupled charge), =4.75GPa；fracture toughness of II type fracture in V rock: , and =1.22MPa.m1/2 ( Runqiu Huang[5]).
According to Table 2, blasting dynamic stress field could significantly affect the critic water pressure.

Aspect ratio of crack is one of key factors of fatigue strength prediction in engineering design and civil structures using fracture mechanics and nondestructive inspection.
Using their geometry approximations, we can evaluate various properties of fatigue phenomena.
Keer, ‘Stress intensity factors for cracks of arbitrary shape near an interfacial boundary’, Engineering Fracture Mechanics, 1987, 21, (1), 27-41
Yagishita, ‘Variation of mixed modes stress intensity factors of an inclined semi-elliptical surface crack’, International Journal of Fracture, 1999, 100, 207–225
Takase, ‘Stress concentration factors for round and flat test specimens with notches’, International Journal of Fatigue, 1995, 17, (3), 163-178.

However, the safety factor obtained by this method usually have non-deterministic human factors.
Obviously, this is also determined by an amount of non-identified human factors.
They belong to the soft rock group, and the water physical properties are very poor.
After encountering the water, the mechanical properties are relatively low.
Once the invading surface and the external factors induced the slope instability are formed, it occurs landslide

While the chips are forming in machining process, the material undergoes severe plastic deformation which affects the integrity of the machined surface and changes the hardness as well as other mechanical properties of both the chip and the machined surface [3].
The factors that affect the plastic deformation in the machined surface include given machining parameters (depth of cut, feed rate and cutting speed), tool geometries (tool rake angle, tool relief angle, inclinational angle, etc) and workpiece material properties (material strength coefficient and strain-hardening exponent).
Thus, cutting speed indirectly affect the values of surface shear strain.
The microstructure and properties of a nickel base superalloy FGH95, J.Univ.
Microstructure, properties and heat treatment process of powder metallurgy superalloy FGH95, J.

Factors that affect the composition of rice husks is geographical situation, in addition to the type of fertilizer and rice varieties also play a role.
In order to emphasize the properties of SiO2 phase extracted and obtained from the rice husk ash, Zeiss brand of EDS (Energy-Dispersive X-ray Spectroscopy) analysis was used.
In addition, due to the presence of SiO2 and other components as rubber filler, rice husk ash has different properties.
Through the mechanical properties tests carried out in this research, the hardness of 62 GPa and the ability to withstand pressure, are lower than the silica products obtained commercially.
Improved characteristics, including properties, modulus, hardness and crack resistance were carried out by adding rice husk ash SiO2 filler to the rubber composite.

Based on the condition of comprehensively considering the nonlinear factors, such as backlash helical gear transmission, time-varying meshing stiffness and composition error, a coupled nonlinear dynamics model of the multi-DOF bending - torsion - axis - pendulum helical gear is built in this paper, and on the basis of the "piecewise linear" backlash function, getting backlash function that is fitting for helical gear transmission system meshing characteristics through high order fitting.
Introduction Gear transmission system is one of the widely used mechanical transmission devices, its mechanical behavior and performance has an important influence on the whole machine, thus, it occupies an important position in the mechanical equipment.
Due to backlash, integrated error, time-varying mesh stiffness, support gap and other factors in the gear transmission system, it leads to a gear system becoming a strong nonlinear system.
For judging and preventing various problems in the later stage of gear transmission system and the engineering practice, it has important theoretical significance to know the change of the mechanical properties.
Establishment of the Bend-Torsion-Shaft-Pendulum Coupling Nonlinear Analysis Model of Helical Gear By considering the meshing characteristics of helical gear, and then combined with the premise of the influence factors of helical gear transmission system, the bending-torsion-axis-pendulum coupling nonlinear analysis model of helical gear is established.

Researches have proved that many factors associate with repairing can affect the residual stresses.
The thermal and mechanical properties of these metals are illustrated in Fig. 3 [8,9].
The material properties associate with thermal analysis are density ρ (kg/m3), specific heat capacity cp (100 J/(℃·kg)) and thermal conductivity k (10 W/℃·m).
The material properties associate with mechanical analysis is elastic modulus E (100 GPa), yield strength σs (100 MPa), Poisson’s ratio μ and the coefficient of thermal expansion α (10-5/℃).
Temperature-dependent material properties of the 12Cr1MoV/P91 dissimilar pipe.

There are many factors affecting the dent resistance, which also lead to the interest of researchers [4-7].
Its material properties are shown in Table 1.
Table 1 Material properties of 6k21-T4 aluminum alloy sheet.
Thilderkvist, Influence of material properties and stamping conditions on the stiffness and static dent resistance of automotive panels, Mater.
Matlock, Material and design factors influencing the quasi-static dent resistance of steel body panels, Soc.

It is known that the unevenness of the cutting depths during the cutting processes, the different physico-mechanical characteristics of the processed materials, values as well as the parameters variation of the working regimes can lead a wear more or less pronounced of the used cutting tools.
The lubricant presence in the cutting area may contribute to the friction and thermal field values reduction, affecting the wear processes.
It can be said therefore that, the tools durability is influenced by all these factors, which requires decisions and actions to reduce the tools or/and the cutting inserts wear processes.
Introduction During the cutting process the tool wears out, due to the high contact pressures, to the high temperatures, to the relative velocities and shocks between the contact surfaces tool-part, but also due to the mechanical and thermal stressess which appears on the tool active faces, having as effect the cutting capacity loss and the processing quality diminishing.
It is mentioned as being the most rough the TiCN, Al2O3 is the most inert from chemical point of view, and the TiN is a material whose characteristics combines advantageous the properties of the other two.

The material and shape of shell are the important factors affecting catalytic converter efficiency and service life.
In addition to these factors, such as catalytic converter design, manufacture and installation method, it associates closely with the engine combustion process and vehicle running condition.
The factors affecting the service life of catalyst are mainly four categories, namely thermal inactivation, chemical poisoning, mechanical damage and catalyst coking.
Generally, lead is added to the gasoline in the form of tetraethyl to increase gasoline antiknock property.
Mechanical damage.