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Then after the static test of simply supported beam, the phenomena of simply supported beams before and after fire were compared in order to determine the damage degree of mechanical property.
Due to the high temperature environment in the fire, a variety of mechanical performances of steel and concrete in reinforced concrete structures continuously decrease with the increase of temperature.
One of the main reasons for the deterioration of the bearing capacity and limit of fire resistance of structure is the degradation of material properties [2-3].The fire will lead to unrecoverable damage of reinforced concrete structure and affect the working performance.
Specimen design According to the fire damage beam mentioned by an organization with the inspection report, and taking the influencing factors of the experimental conditions into account, the test specimen beams were made by the appropriately scaled.
The reduction factor: of steel elastic modulus was defined as the ratio of elastic modulus and the elastic modulus at room temperature in the condition of steel experiencing the temperature t and cooling.

Introduction SiCp/Al composites are characterized by its excellent physical and mechanical properties such as high strength, high stiffness, wear resistance, antifatigue, high fracture toughness, good heat stability and low coefficient of linear expansion, so these materials have found extensive applications in aviation, aerospace and other industries [1].
However, the cutting processing is very complicated, and factors that affect the tool wearing are not limited to the impact of SiC particles but include built-up edge and the diffusion and oxidation of chemical elements at high temperature, etc.
The material properties are shown in Table 2.
The factors and level parameters are shown in Table 3.
Muthukrishnan, in: ASME International Mechanical Engineering Congress & Exposition, American Society of Mechanical Engineers publishers(2009) [7] Wenfeng Zhang, Xiaonan Pan: Journal of Materials Engineering. (1999), p. 14(In Chinese) [8] N. muthukrishnan, J.P.

To make the simulation results more reliable, these important elements are also taken into account, such as temperature-dependent properties of material, the phenomenon of plasma channel radius expanding, the percentage of discharge energy transferred to the workpiece and Gaussian distribution of heat flux.
In this process, high temperature gradients are produced, which bring about thermal stresses in a small heat affected zone.
Fig. 1 Finite element geometric model Fig. 2 Flow chart for the computing procedure Table 1 Relevant material properties of steel Temperature(oC) 25 100 400 1000 1500 Thermal conductivity(J/s m K) 47.68 43.53 36.02 27.53 24.02 Specific heat(J/Kg K) 460 465 475 650 665 Elastic modulus(Pa) 2.05E11 1.95E11 1.80E11 0.70E11 0.40E11 Yield strength(Pa) 1.20E9 2.40E9 0.93E9 0.44E9 0.07E9 Thermal analysis.
The size of heat flux on the workpiece surface is an essential factor in the model of the micro-EDM process.
Some researchers considered the spark radius is time-dependent, while some considered the current pulse affects the spark radius.

Indeed, due to their intrinsic characteristics, laminate composites are characterised by poor mechanical properties in the out-of-plane direction [3].
The mechanical properties of the reference material are presented in Table 1, while in Table 2 nanoparticles’ properties are listed.
Table 1: RTM6 - Tenax HTS 12k mechanical properties.
E1 [MPa] E2 [MPa] G12 [MPa] G12 [MPa] ν12 ν12 t [mm] 135000 8500 4200 4200 0.35 0.35 0.190 Table 2: Nanoparticles’ properties.
Modeling of the mechanical properties of nanoparticle/polymer composites. (2005) Polymer, 46 (2), pp. 553-562

The Applied Research of Numerical Simulation Techniques in the Forming of Covered Parts of Automobile Hui Yong Yu1, a,Hui Lin Zhou1, b, Jun Hua Hu2,c 1Department of Materials Engineering, Henan Mechanical and Electrical Engineering College, Xinxiang, 453002, China 2 College of Materials Science and Engineering, Zhengzhou University, HeNan, Zhengzhou, 450002,China ayuhuiyong_123@163.com, b zhl801209@163.com, c26866355@qq.com Keywords: Numerical simulation, DYNAFORM, Car beams Abstract.
Introduction The automobile has a large outline and a complicated structure , which was affected in the process of forming by many factors, such as material properties, blank and mould shape, draw bead form and layout, press direction and speed, friction lubrication conditions, the size of the blank-holder force and so on, involving geometry nonlinear, physical nonlinear and boundary nonlinear problems.
Among them, the mandrelling process is the foundation and the key to other processes and the forming quality of drawing parts will directly affect the progress of the subsequent process[4].
This suggests that increasing blank-holder force can't affect well[5].

Virgin aggregates properties.
Characterization of viscoelastic properties.
Determined viscoelastic properties of the material are introduced into the FE model.
Material properties.
Figure 9 shows the shift factors calculated with WLF at 15°C temperature for BBREF_5,3 and BBRAP_3,7.

The elasto-plastic properties of the material are described by Von Mises yield criterion and stress-strain of uniaxial cyclic loading.
Introduction The fatigue of material under random scanning vibration is a complex problem, there are many influencing factors, and most influential factors can not be described quantitatively by mathematical methods until now.
In recent years, although the properties of cyclic stress-strain, the relations between cyclic stress and fatigue, cyclic strain and fatigue life, of metal material have been studied [1-3], but these studies did not involve high frequency.
The shell structures of notched torus are used in motor of aircraft commonly, and the cyclic loading is put on it usually, fatigue is the major factor to affect the fatigue life.
Taking into account the two factors of entire frequency scanning and high-frequency, the revised factor should be: λ = 0.4 ~ 0.6.

In this study, sintered iron was machined and the influences of resin impregnation on its thermal properties, coefficient of friction, and flow stress (deformation resistance) were investigated.
Since the machinability of impregnated compacts is determined by various factors in a complex way, in addition to conducting drilling and 2D cutting experiments, various tests were performed to individually investigate possible causes.
To this end a ring compression test was conducted to valuate the coefficient of friction, the thermal properties were measured to investigate the cutting temperature, and a compression test with grooved dies was performed to determine the embrittlement and flow stress (deformation resistance) of the material.
The thermophysical properties that affect the cutting temperature of wrought material are the thermal diffusivity K and the product λρc (where λ is the thermal conductivity, ρ is the density and c is the specific heat).
(2) The increase in machinability caused by resin impregnation is not caused by a reduction in the coefficient of friction or by a modification of the thermophysical properties.

The main constraining factor for their use in highway and railroad building is their physico-mechanical deterioration when they are wet: they demonstrate extreme water absorption, swelling, stickiness, plasticity and stress reduction.
Therefore, the problem of developing the “efficient” modifiers of clay soils that can improve their strength properties without lifetime reducing seems to be important.
In this work we study the effect of nano-scale chemical additives on physico-mechanical properties of clay soils; specifically, the montmorillonite clays are taken as an example.
To calculate the energies and the structure properties of montmorillonite clusters we used the set of quantum-chemical software kit – MOPAC 2009 (Version 11.038W), parametric model – PM6.
Fig. 2 Total energies of the layered structure fragments of montmorillonite with inserted ions It is known that water can significantly affect physico-mechanical properties of clay soils.

A Unified Cutting Force Model for Flat End Mills Based on Cutter Geometry and Material Properties ZHANG Xiaodonga *, HAN Ceb, ZHANG Dinghuac* and LUO Mingd Key Laboratory of Contemporary Design and Integrated Manufacturing Technology (Northwestern Polytechnical University), Ministry of Education, Xi’an 710072, China aavail_2006@126.com, bhance@mail.nwpu.edu.cn, cdhzhang@nwpu.edu.cn, dluoming@nwpu.edu.cn Keywords: Cutting force; Oblique cutting; Flat end mills; Cutter angles; Material properties Abstract.
In this model, the cutting force is bridged among cutter geometry, material properties and cutting parameters.
The cutting force coefficient includes all the information of chip deformation in cutting process depended by cutter geometry and material properties, but it is simply defined as a constant in cutting force prediction.
However, chip thickness is an important factor in metal cutting deformation process which affects material properties.
Cutting velocity and feed rate per tooth are the variable factors in the identification tests.