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The reasons for large deformation properties in Baozhen Tunnel were analyzed and corresponding supporting measures were carried out in this paper.
Analysis of deformation characteristics in Baozhen tunnel Deformation characteristics are influenced by not only the mechanical properties of surrounding rock but also in-situ stresses and construction factors (Liu, 1999)[2].
Curve fracture and break Fig. 1 Failure Characteristics of Surrounding Rock in Tunnel Generally speaking, the process and features of progressive failure are mainly affected by three factors below: (1) The size and state of the in-situ stress.
It is also one of crucial factors, which may bring about geopressure symptoms and mechanical disasters during excavation and maintenance
Fig. 4 Horizontal convergence rate at DK79+127 Fig. 5 Vault settlement rate at DK79+127 Through the analysis above, surrounding rock in Baozhen Tunnel presents properties of large soft rock deformation so the supporting countermeasures should be taken in large deformation part.

Although AZ91 alloy offers a good combination of mechanical properties, it is unsuitable for use at temperatures above 120 °C due to its poor creep resistance and its large decrease in strength at elevated temperatures [5].
Despite the enormous role of the various factors of the constituent phases, however, mechanical behavior of Mg alloys has not been investigated based on the concepts of two-phase materials.
However, different microstructural features between squeeze and die cast alloys such as grain and particle sizes will affect the tensile and creep properties differently [8].
Tensile and Creep Properties.
The room temperature tensile properties are shown in Fig. 3.

Introduction Ultra-fine grained (UFG) metallic materials produced by severe plastic deformation (SPD) have attracted a growing interest owing to their superior mechanical properties without alloying [1,2].
Moreover, it is well known that sliding wear behavior is influenced considerably by not only the mechanical properties of the materials but also the adhesion to the counter material, which would be affected by the microstructure of the friction material.
Wear properties of HPT processed S45C carbon steel were investigated using a ball-on-disk friction method.
Results and Discussion Wear Properties.
Adhesion Properties.

To fulfil this function, cladding must have good thermal and technical properties.
This achieves the optimum ratio of expended financial costs for revitalisation and improvement of the thermal and technical properties of the structure.
The thermal and technical properties of the building envelope have a significant influence on the energy performance of the building.
This is a decisive factor affecting both finances and environmental protection.
It is dependent on many factors, such as weather conditions, quality of maintenance or manner of use.

As the soil is a three-dimensional system which consisting of three parts named as solid particles, water and gas, the mechanical properties of the soil is quite complex under the long-term farming and compaction.
Zhang Rui et al[23] presented the details of application on simulating the soil mechanical dynamic behavior in the field of terramechanics, analyzed the feasibility of the application of DEM to describe soil dynamic property, pointed out a new direction for soil contact problems.
Ying Chen et al[25] analyzed soil-plow contact model in three different soil conditions, and indicated that the discrete element method can be used to analyze the soil-tool contact performance, but it is more complex to analysis the soil disturbance than soil cutting force, and the future directions is to study the relationship between dynamical behavior of the discrete element particles and the microscopic properties. 3 Problems For some results of the two directions in the study, there are many influenced factors in soil-tool contact model; factors to be considered by these studies are different.
Various factors should take into account in the future research; In the study of soil-tools contact force , due to the complexity of the force, it is necessary to consider the force in several directions, as well as the dead load on soil and the force on the tool.
In soil cutting, the ultimate goal to use the discrete element method is to get the changes of soil properties and the mechanical behavior, and provide the basis for design cutting tools.

Previous research found that SMD is affected by physical properties such as viscosity, surface tension and injection pressure [13-16].
The parameters that affect spray cone angle are atomizer design (dimension of the discharge orifice), liquid properties (viscosity and surface tension) and injection pressure [10, 17-20].
Three properties of palm olein blends that affect the characteristics of the spray were measured: kinematic viscosity, density and surface tension.
Table 2 shows the result of physical properties measurement.
Rollbuhler, Factors Influencing the Effective Spray Cone Angle of Pressure-Swirl Atomizers.

Performance of mechanical products depends largely on the parts surface processing quality, the failure of mechanical parts, usually starts from the surface layer; a good surface quality can improve the accuracy of parts, wear resistance, corrosion resistance and fatigue strength [1,3].
Due to the quality of PM60 mould steel after processing is affected by many factors, influencing factors of cutting process are complex, the fluctuating range of cutting parameters are relatively great.
Ltd., the workpiece size was 130 mm×40 mm×40 mm, the chemical composition of workpiece material is shown in Table 1, physical properties is shown in Table 2.
Table 3 Cutting factors level code table Factors Codes Levels 1 2 3 4 Spindle speed n( r/min) A 8000 10000 12000 14000 Feed speed vf (mm/min) B 300 450 600 750 Depth of axial cut ap ( mm) C 0.5 1 1.5 2 Radial depth of cut ae ( mm) D 0.15 0.3 0.45 0.6 Results and Discussions Response Analysis of Signal-To-Noise (S/N ratio).
The greater the value of variable factors explained the large fluctuations of the test.

Spindle performance directly affects the accuracy, stability and range of machining system and applications, thermal characteristics of which has a crucial role during processing.
For spindle thermal properties of a number of scholars at home and abroad have carried out some research.
International Mechanical Engineering Congress and Exposition, Anaheim, CA, USA, 1998
Research on motorized spindle’s thermal properties based on thermal contact.
Thermo-mechanical model of spindles.

The mechanical tensile testing machine (Perkin Elmer Diamond SII DMA), equipped with 18 N load cells, was used for measuring the mechanical properties of the hydrogel.
The reason may be that the polymer chains are highly entangled and resistant to deformation when hydrogel is in the unswollen state, but when the hydrogel is in the swollen state, influxing by the buffer ion and water molecule, its distance between polymer chains get bigger and chains became disentangled, it can’t resist the deformation, which result in the lower mechanical properties.
The Young’s modulus value is also affected by the environment ionic strength, as to the same pH value level, the higher ionic strength is, the higher Young’s modulus value is.
Conclusion The mechanic feature of the hydrogels both sensitive to pH and electronic field strongly depends on the equilibrium swelling ratio, that is the pH value of the solution, increasing the pH value, the mechanic feature of the hydrogel would decrease, which the largest span can reach 80%; The hydrogel would change its volume with adding the electronic field, when increasing the DC value, the swelling ratio would decrease, and the ionic strength is another factor that affects the equilibrium swelling ratio, the higher the ionic strength is, the bigger the decreased span is.

Mechanism of bank collapse Collapse of the reservoir bank is affected by many factors (water, soil, wind and other factors).
The physical and mechanical properties of rock and soil are part of the internal factors of bank collapse while water is the main external factor which causes bank collapse.
However, the influence degree of these factors is different because of the differences in bank slope structure.
The reservoir banks are made up of steep rock that has formed as a result of joints and fissures; the banks are easy to collapse along the opened fissure by the affects of many factors (water, wind, other external geological agent).
Appropriate treatment measures could be formulated after adequate considering and weighing different factors .