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Based on the above several factors, the authors added damping structure at the corresponding position, and established finite element model, which is shown in figure 2.
In the selection of damping material, we should first consider the working temperature, because the properties of viscoelastic damping material is affected by temperature and frequency, and the influence of temperature on the properties is particularly notable.
The loss factor and elastic modulus of QZD damping materials are lower.
Tab.1 The properties of viscoelastic damping material Materials Poisson's ratio Elastic modulus (MPa) Loss factor Optimum temperature Loss factor at the peak of vibration (ηmax) Modulus ηmax (MPa) SA-3 damping 0.49 100 0.89 25℃ 1.36 235 DFM damping 0.49 44 0.88 30℃ 1.03 53.9 QZD damping 0.49 15 0.21 10℃ 0.63 40.0 ZN-1 damping 0.49 2.4 0.9 20℃ 0.98 7.5 During finite element calculation, the specified working temperature is 45℃, the frequency range is between 145Hz and 190Hz, loss factor of SA-3 damping material is between 0.89 and 1.05, elastic modulus is between 100MPa and 110MPa.
In addition, the heat conduction of damping material is lower, increasing thickness of damping layer can make the box exchange heat with the outside not easily, increase the surface temperature of the box, which directly lead to the decrease of damping properties of damping materials.

The resonant frequencies and quality factors of MEMS and NEMS depend critically on the layer quality and the residual stress in the SiC/Si heterostructure.
Introduction The superior mechanical properties of SiC like the high Young's modulus, the extreme mechanical hardness and stiffness predestines this material for microsensors and microactuators in micro- and nanoelectromechanical systems (MEMS and NEMS).
To extract the properties of every layer in the heterostructure model calculations have to be carried out to account for the phonon vibrations and damping factors.
The phonon properties were determined by modeling of the obtained Ψ and ∆ spectra in the region between 600 and 1200 cm -1.
The strain variation across the wafer can be affected by two main factors.

The results show that impact factors of the bridge increase as surface roughness deteriorated; the impact factor varies obviously for the different component; the tension impact factor of the short suspender is larger than that of long ones; damping ratio of structure has little effect on the impact factors.
Impact Factors of Displacement and Cable Tension.
Fig.6 Impact factors of the arch ribs in mid span Fig.7 Impact factors of main girder in mid span From Fig.8 can be seen that the resonant frequencies rather approach to the 3rd, 5th and 9th bending vibration mode of the bridge, while at other velocities the resonant frequencies deviate those causing the deflection impact factors descending greatly.
Fig.10 Impact factors of axial force of cable 1 Fig.11 Impact factors of axial force of cable 8 Conclusions The dynamic properties for a crescent-shape heterotypic CFST bridge due to moving vehicle are investigated.
Mechanical vibration-Road surface profiles Reporting of measured data.

According to the experiments study of sulfuric acid saline soil, the formula of compression coefficient with the changes of moisture content, salt content, initial dry density and temperature is presented, and the interaction law between the various influencing factors on sulfuric acid saline soil compression are analyzed in the paper. g@bjjtxy.bj.cn Introduction With the rapid development of high-grade highways in China, it becomes increasingly important and urgent to study the engineering properties about special soil.
These factors would affect the compressibility of the sulfuric acid saline soil and make it has its own characteristics.
The level of the factors is seen in Table 1 by regression orthogonal design requirements.
The analysis of the interaction between the various influencing factors on sulfuric acid saline soil compression The interaction between the various factors can be reflected by contour lines.
The interaction of moisture content X1 and salt contentX2 Fig. 1 The interaction of moisture content X1 and salt content X2 From Fig.1, it can be found the following conclusions: (1) Overall, the interaction between the two factors, the main factors affecting the compression coefficient is the salt content ( It is due to the space of contour line is small.

The microstructures and the mechanical properties of MoSi2 based composites were investigated by means of SEM, EDS, XRD and three point bending test. 1.
Especially, the high temperature mechanical properties of MoSi2 based composites are a very important factor for their practical applications.
The full density must be also secured for the high temperature applications of MoSi2 based composites, since the porosity created under consolidation processes affects mechanical properties and oxidation behaviors of the material.
Mechanical properties of monolithic MoSi2 and MoSi2 based composite materials were evaluated using three point bending tests.
Such a thermodynamic analysis by the reaction of MoSi2 and ZrO2 was confirmed in the previous results [13]. 3.2 Mechanical properties Fig. 4 shows the effect of SiC, NbSi2 and ZrO2 particles on the room temperature mechanical properties of monolithic MoSi2 material.

In addition, such structures exhibit better mechanical properties than strut-based ones with similar porosities.
Moreover, CE caused wall thickness (Fig. 4) and mechanical properties degradation.
USV treatment completely removed powder from inside (Fig. 4) and did not significantly affect the wall thickness and mechanical properties, Table 2.
The powder was removed by PRS with USV support, which did not affect mechanical properties of the FGPS.
Certain amount of through-hole defects in the WT- manufactured sheet-based structures would not generate problems for the implants as long as it does not affect the mechanical properties.

But still, the factors that affect the increase of temperature are not well-known.
Besides, in [10] it can be seen that the steel wool fibers may deteriorate the mechanical properties of the mixture in case fibers are not well dispersed.
Thermal Properties of Dense Asphalt Concrete with Steel Wool Fibers.
In fact, with the addition of steel wool fibers it is very easy to change the air void content of dense asphalt concrete to the point that the mixture may lose its mechanical properties.
Homogeneity and mechanical properties of dense asphalt concrete with steel wool fibers.

Mass of the specimens is the factor that affected the density and the mass is decrease with the increasing of fiber content.
Mechanical Properties and Fracture Behaviour of Coconut Fibre-Based Green Composites.
Materials and Mechanical Properties of Pretreated Coir-based Green Composites, Composites:Part B, 40, 633
Mechanical and dynamic properties of coconut fibre reinforced concrete.
Improvement of the mechanical properties of jute fiber reinforced cement mortar: A statistical approach.

TB6 titanium alloy is widely used in aerospace industries because of its good comprehensive mechanical properties, low density and good corrosion resistance [1].
Mechanical properties in normal and high temperature are shown in Table 2.
Table 1 Chemical composition of TB6(mass fraction, %) Element H O N Fe Al V Ti Wt pct 0.01 0.03 0.03 1.93 2.95 10.15 balance Table 2 Mechanical properties of TB6 Normal temperature ≥ High temperature ≥ tensile strength σb/Mpa 1005 testing temperature ℃ 350 yield strength σ0.2/Mpa 1035 tensile strength σb/Mpa 963 elongation δ/% 11.1 fracture strength σ100/Mpa 840 shrinkage rage ψ/% 64.4 elongation δ/% 16.8 impact value аk/J·cm-2 60 shrinkage rage ψ/% 70.8 Simulation model and processing condition.
In addition, contact length of milling cutter and chip increase outgoing area of cutting calories. several factors make the temperature increase slowly.
Heat affected zone on milling cutter reduce with increasing of vc.

The ceramics exhibited a high temperature of maximum dielectric permittivity at (Tmax = 343 °C at 100 kHz) along with electromechanical coupling factors (kp = 0.34, d33 = 147 pC/N).
This demonstrates that potassium affects the Tm (transition-temperature).
Electromechanical properties The spectra of electrical impedance and conductance versus frequency, that were obtained by an Agilent 4284A precision impedance analyzer, were used to determine the electromechanical coupling coefficient kt, mechanical quality factor Qm and acoustic impedance Z.
Figure 16 shows an inverse relationship between the mechanical quality factor Qm and the dielectric loss (tanδ).
Mechanical quality factor Qm and frequency constant Nφ according to content of xKBT Fig. 17 shows the electromechanical and piezoelectric properties of (1-x)NBT-xKBT systems.