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For numerical analysis, the physical properties of the vehicle model are: ms=28860kg; Jθ=60000kg·m2/rad; cs1=30000N·s/m; cs2, cs3=40000N·s/m; ks1=474000N/m; ks2, ks3=6756000N/m; mt1=228kg; mt2, mt3=456kg; ct1, ct2, ct3=40000N·s/m; kt1=1600000N/m; kt2, kt3=2000000N/m; a1=1.8m; a2=1.7m; and a3=3.2m.
Simulation of road surface roughness Road surface condition is a very important factor that affects the dynamic responses of both the bridge and vehicles.
Because the bridge responses due to moving vehicle loads are affected by many factors, the effects of road roughness, vehicle velocity and bridge damping on bridge responses are analyzed in present study.
When the bridge damping increases, the typical responses of bridge and their dynamic amplification factors decrease.
However, the dynamic amplification factors of typical responses of bridge decrease without large amounts.

Especially the FRP plate is a kind of resin material and its physical and mechanical properties will change with temperature and time.
In recent years, many domestic and foreign experts and scholars put forward the method which used FRP sheets or plates to strengthen structures and research on its mechanical behavior [1-7].
The temperature and creep effect are the main factors impacting on the working mechanism of FRP.
Simultaneously, under external loading, the relative slip occurred on the interface between FRP plate and concrete causes the redistribution of stress and then influences mechanical behavior of component.
The elastic modulus of FRP plate affected by temperature and time is defined by the equation as below

Composite made of such fabrics has been widely used in various areas such as aerospace, military, transportation and energy for its many advantages including light weight, high strength and good mechanical properties.
The which is front side tension decreases, and the which is back side tension increases; Euler's formula on flexible body can be applied here 0： or In this formula, is warp angle；μ is friction factor between the weft and the warp（μ refers to dynamic friction factor when relative motion happens between wefts and warps；μ refers to static friction factor when there is no relative motion）.
Assuming that the frictional factor between yarns is =0.4, =, Assume the density of reed is 150/10cm and the reed width is 50cm.
We can zoom up the result of resistance by multiplying a correction factor.
Journal of Textile Research,2009,30(8):34-38 [4] XU Haoyi.On the nature of beating-up and factors affecting its friction [J].

Due to these unique properties, PI has been developed into membranes for the separation of gases and vapors [5].
They have received significant attention in recent years due to several unique and favourable properties, such as their negligible vapour pressures and high solubility for organic and inorganic species.
H2, CO2, CO, N2 and CH4 permeability properties of the membranes were measured at temperatures of 35 °C, 100 °C, 150 °C, 200 °C and at pressures from 2 bar to 6 bar.
Results and discussion CO2, CO, H2, N2 and CH4 permeability properties of the composite [C4mim][NTf2] and PI membranes were calculated and are shown in Figure 2.
H2 is affected less than CO, therefore the H2/CO selectivity is increased.

The mode of damage will subsequently affect the fracture behaviour of the material and shorten the lifetime of the component.
The first case uses elastic-plastic properties assuming a uniform and uncracked surface.
Introduction The oxidation, environmental corrosion and creep damage are limiting factors in the life assessment of engineering components operating at elevated temperatures.
Figure 1: Surface cracking in an oxidised 316H stainless steel sample Figure 2: Hardness variation in an oxide 316H stainless steel material Indicative Mechanical Properties of the Oxide Layer The indicative variation of mechanical properties in an oxidised 316H stainless steel (SS) sample has been evaluated using the Vickers hardness data shown in Figure 2.
The two mechanisms described are relatively independent but can interact with each other due to geometrical and material properties change during the period.

The mechanical properties of masonry structural members strengthened by FRP (Fiber Reinforced Polymer) are affected by the bond strength of the reinforcement interface, in addition to the strength of the material FRP itself.
Lee et al. published the results of the research on the SFRP reinforcement test for reinforced concrete beams with cracked damage [2], pointing out the effect of some factors such as fiber spray layer thickness, fiber length, fiber material and fiber pre-stressing.
Although some experimental studies have been carried out on the influence of humidity and temperature on the bonding properties of FRP externally reinforced concrete members, there are few related studies on that of FRP-reinforced masonry members [6,7].
It is known that water erosion causes the physical mechanism of FRP to age and the mechanical properties of the resin to decrease [8].
Moisture also affects the fiber-matrix interface properties through chemical processes and resin swelling after moisture adsorption [10].

In the test, the deformation properties of composite shear walls and the development law of the strain of concrete and steel were studied.
The research production has provided a foundation for the further exploration to the working properties of the composite shear wall under cyclic loading.
The key to ensure this kind of composite wall to work well is to have a good interface bonding properties between the composite cement slabs and concrete.
Although they both belong to cement-based materials, which are similar on the basic physical and mechanical properties and with good adhesion basis, but as the interfacial bonding properties are affected by a variety of factors, such as the interface conditions, the quality of the concrete pouring, and the force status, the uncertainty whether composite cement board and the concrete can work together well is brought by those factors.
Firstly, the development rule of the overall deformation properties of the composite shear wall and the strain properties of each part of the wall was studied[6-7].

Fatigue Crack Growth Rate of High Strength Pipe Steels Kai Wu1, a*, Hong Zhang1, b, Mengying Xia1, c, Jingtian Wu1, d, Xiaoben Liu2, e 1 College of Mechanical and Transportation Engineering, China University of Petroleum (Beijing), No 18, Fuxue Road, Changping District, City Beijing, P.R.CHINA 2 SINOPEC Tianjin Liquefied Natural Gas Co., Ltd., Tianjin 300457, China awk0609@126.com, bhzhang@cup.edu.cn, cxiamengying322@163.com, dwujingtian074@163.com, eliuxiaoben1991@126.com Keywords: High strength pipe; Fatigue crack growth; Experimental study; Regression equation Abstract: Fatigue crack growth rate is a significant mechanical property of high strength pipe.
Some properties of fatigue crack propagation can be obtained by evaluating the mechanical performance of the material.
Fatigue crack growth rate, which is a significant mechanical property of pipeline steel, is an important experimental basis for tolerance analysis of structural damage [1].
There are many factors that affect the fatigue crack growth rate, such as: the stress intensity factor ΔK, cyclic stress ratio R, waveform and condition.
Wang, X.D Wu, Study on rotational factor of Strain Fatigue of CT specimen, Acta Metallurgica Sinica. 1992(20) 38-45.

Therefore its surface properties are the key ones.
The structure and chemical properties of the HNT surface are sufficiently studied [19-21] and have a number of characteristic features shown.
The aggregative stability is mainly provided by the adsorptive-solvate, structural-mechanical, and entropic factors.
Its stabilizing effect is mainly connected with the formation of steric hindrances to aggregation due to the adsorptive-solvate as well as structural-mechanical factors of stabilization.
Theng, Interactions of Halloysites with Amides: Mineralogical Factors Affecting Complex Formation, Clay Minerals. 19 (1984) 161-75

But the electrical resistivity of RB-SiC had not affected by the oxidation at 900�.
The oxidation mechanism of RB-SiC and the affecting factor on oxidation of RB-SiC were analyzed and discussed.
Though the effect of high temperature oxidation on silicon carbide mechanical properties has been understood long before and studied [1-3], the studies on the oxidation of reaction-bonded silicon carbide (RB-SiC) are reported seldom.
It can be seen that the oxidation of RB-SiC didn't affect its electrical resistivity and the RB-SiC with large particles sizes still held lower electrical resistivity.
The microstructures of RB-SiC were sounder and the oxidation of RB-SiC took place on it surface, so that the oxidation of RB-SiC could not affect its electrical resistivity.