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The experiment result demonstrates that the experiment method could simulate the dangerous conditions during the real construction and check the stress effectively which can provide technical support for the construction of similar bridges. 1．Introduction Arch-girder combination bridge becomes more and more important in bridge construction because of its outstanding mechanical property and good adaptability for construction [1].
Its properties are showed as follows.
This experiment took the contour size and thickness as fundamental dimensional analysis factors.
That is to say, wind load is nonlinear factor.(3)There is nearly no residual stress after unloading.
(6) Rigidity, weight, length and other factors should be taken into account, so that large stress and deflection of launching nose does not appear in the biggest cantilever state

At the present time, as the steam conditions and capability of the supercritical power unit increasing, the unit reliability is an important factor for the unit efficiency.
Introduction At present time, high chromium heat resisting steels have been widely used in power plants because of their excellent mechanical properties.
Table 1 Welding parameters Pass Current, A Voltage, V Welding speed, mm/min Heater current, A Argon flux, L/min Type of welding wire 1 230 14 100 10 20 AWS-5.28 ER90S-B9φ1.0mm 2 230 14 400 40 3 230 14 380 38 0 5 10 15 20 0 200 400 600 800 <100 ℃ <100 ℃ Temperature ( ℃ ) Time (h) 750±20 ℃ Room temperature PW HT Fig.3 PWHT procedure Material properties and welding heat resource model.
At the tube weld joint, the reference line was made along the tube wall thickness of weld metal (WM) and heat-affected zone (HAZ).
FE creep damage analyses were performed for the tube using Eqs. (1) to (4) and the material properties [8].

Surface integrity includes the mechanical properties (residual stresses, hardness etc.), metallurgical states (phase transformation, microstructure and related property variations, etc.) of the work material during processing and topological parameters (surface finish and other characteristic surface topographical features) [13].
Zone-I: Heat affected zone (HAZ), Zone-II: Work-hardening zone (WH), Zone-III: Safe and normal (SN).
From Fig. 2, it can be seen that in general, preheating gives much affects the surface microhardness.
This is area is established as Heat affected zone (HAZ) as shown in Fig. 2 (Zone-I, 450 °C).
Merchant: Basic Factors in Hot Machining of Metals, Trans.

These phenomena will affect the microstructure of the formed part and play an important role in determining the mechanical properties of the deformed products.
Therefore, it is very important to investigate and understand the effect of deformation process parameters on the microstructure evolution in order to improve the mechanical properties of the products.
Ebrahimi et al. studied the dynamic recrystallization behavior of a superaustenitic stainless steel by hot compression test and investigated the effect of deformation temperature and strain rate on the flow stress during dynamic recrystallization by using the hyperbolic sine equation [5]. 20CrMnTiH steel is a low-carbon steel widely used as a gear material in China due to its high hardenability, anti-wear properties after carburization and quenching, and low temperature impact toughness [6-8].
The isothermal hot compression tests were carried out on the Gleeble-3500 thermo-mechanical simulator.
The friction between the dies and the deformed blank was assumed to be of shear type and the friction factor was set as 0.3.

A series of parameters such as power factor, active power and reactive power which change with the voltage and frequency are chosen to demonstrate the load components characteristics in load modeling. [1]Load model is the mathematical expression of the depicted bus power varying with the bus voltage and bus frequency.
As a vital composition in power system, load model is tough to build accurately due to its complexity, distribution, variation and stochastic properties.
(1) (2) Rotor motion equation, electromagnetic torque equation and mechanical torque equation are expressed as (3), (4) and (5) respectively
In order to describe load time-varying property, a parameter is defined as (8), which is to define the initial active power proportion of the equivalent motor in the composite load model
The Synthesis load model structure taking account of the distribution network solves the problem that network impedance affecting the load model accuracy.

Introduction There are many factors affecting the bearing behavior of single pile, of which the variations are now mostly supposed to fit the hyperbola [1~5][10][11].It is the basis for design of pile foundation to determine the ultimate bearing capacity , so evaluating and determining it correctly and reasonably will influence the safety of the entire project and its cost.
Based on the previous researches, the paper analyzes the properties of traditional hyperbola method from the perspective of analytic geometry, derives the a more general form of hyperbolic equations in test pile fitting and discusses the method to determine the ultimate bearing capacity and the corresponding settlement based on the he maximum point of curvature in such hyperbolic curve.
Fig.1 Hyperbolic method in this paper Fig.2 Loading-Settlement curves of O’Neil piles The following is the simplified derivation of the hyperbola property: the coordinate of point O in the coordinate system of (SOQ) is (c,Qult); CS of (xoy) can be transferred into CS(SOQ) by the means of rotation and translation, which will not change the shape of curve.
Chinese Journal of Rock Mechanical and Engineering, 2008,27(6):1260－ 1269.

Therefore, for the motive of designing SCC with excellent workability and mechanical properties, proper factors such as water to binder ratio, mineral admixture and sand ratio should be chosen.
Table 2 Mix proportions and properties of concrete Mix Mix proportion [kg/m3] Slump Flow [mm] T500 [s] Δh [mm] Compressive strength [Mpa] Cement FA GGBS Sand Gravel Water 1 520 - - 826 894 165 635 4.8 20 64.5 2 416 104 - 809 877 165 640 4.9 25 60.8 3 364 156 - 803 870 165 645 3.5 20 57.2 4 312 208 - 795 862 165 655 4.3 20 54.9 5 286 234 - 792 859 165 650 3.5 25 52.7 6 364 - 156 823 892 165 650 4.3 20 62.7 7 312 - 208 821 889 165 645 3.7 25 58.2 8 260 - 260 819 888 165 640 4.4 25 56.9 9 208 - 312 817 886 165 630 4.5 25 52.1 10 260 52 208 814 881 165 635 4.3 25 59.2 11 260 104 156 808 875 165 640 4.2 20 57.4 12 260 156 104 802 868 165 640 3.4 20 56.6 13 260 208 52 796 861 165 650 3.2 15 54.2 Concrete basic properties.
Concrete basic properties, such as slump flow, T500, Δh and compressive strength at 28d are given in Table 2.
Curing age affected the chloride diffusion coefficients obviously.
Study on dense packing properties of cementitious materials.

This relation yields only an approximate value since the heating rate, the attempt-to-escape frequency factors, and the thermal conductivity of the material, affect the exact value of Tm in the material.
In fact, many TL materials also demonstrate OSL properties [34].
Kearfott, Characterization of the glow peak fading properties of six common thermoluminescent materials, Appl.
Rhodes, OSL properties of NaCl relative to dating and dosimetry, Radiat.
Rafique, The optically stimulated luminescence (OSL) properties of various known thermoluminescent (TL) materials, Appl.

Besides, we remind that the final quenching of the sword affects the phase distribution, in terms of martensite and bainite concentration, along the blade cross section.
Results The complementary results obtained from the INES and ENGIN-X measurements allow us to give a clear picture of many factors concerning the samples.
The typical corrosion products, and the apparent anomalies in what would be expected from the ideal Fe-C phase spatial distribution, give information on the conservation status in terms of environmental factors and polishing.
As regards the stress and strain data, the following properties have been analyzed: a) the strain level for axial, transversal and normal directions, using the lattice parameter value measured in the tang as a reference; b) the full width at half maximum of the 211 Bragg peak for axial, transversal and normal directions; c) the ratio between the Lorentzian and Gaussian components of the 211 peak.
A full map of all these properties has been compiled for both the blades.

Introduction The Mobile hard disk is a precise micro-electro-mechanical system, which is mainly made up with shell, PCB(printed circuit board) and hard disk.
Due to complexity of structures of mechanical components and special work mode, the HDD is very sensitive to vibration.
The contact and the impulse with ground affect the whole process of drop impact.
The table has four factors(design variables).
Each factor has 25 levels. 25 groups of tests can be proceed. 25 samples are come into being. 20 samples are chose as training set among them. 5 samples are chose as test set using for detecting network.