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Analytical solutions of stress intensity factors and crack opening displacements are obtained.
Thus, the trans-scale stress intensity factor is obtained as (1) (2) Kmacro micro is the trans-scale stress intensity factor. nmacro is the macroscopic Poisson’s ratio. mmacro and mmicro stand for the macroscopic and microscopic shear modulus, respectively.
The second involves the macroscopic and microscopic material property.
Influence of microscopic effects on the fatigue crack propagation behavior The microscopic effects include the size a0 of the initial micro-flaw and the evolution modes of three basic normalized parameters s*, d* and μ* that greatly affect the fatigue behavior of a material.
D dissertation, Department of Mechanical Engineering and Mechanics, Lehigh University, USA, 1962

Table 1 shows the specific mechanical properties of concrete.
Table 2 shows the mechanical properties of steel bar.
The properties of CFRP sheet were from the manufacture's reported data, and are showed in Table 3.
Table 1 Properties of Concrete Strength Grade Cube Compressive Strength [MPa] Modulus of Elasticity [GPa] Poisson's Ratio C50 67.7 34.7 0.2 Table 2 Properties of Steel Bar Reinforcement Type Diameter [mm] Yield Strength [MPa] Ultimate Strength [MPa] Modulus of Elasticity [GPa] HPB 235 10 376.7 528.5 210 HRB 335 25 370.3 552.6 185 Table 3 Properties of Composite of CFRP Sheet Tensile Strength [MPa] Modulus of Elasticity [GPa] Elongation [%] Surface Density [g/m2] Nominal Thickness [mm] 3696 241 1.7 300 0.167 Design of Specimen.
The author recommends that the target displacement ductility μtar needs to be magnified and the magnification factor λ=1.5 is suitable.

In the case of bismuth telluride based materials, that have a layered structure and can be easily cleaved along these layers, the use of polycrystalline materials improves their mechanical properties.
Recently the factors affecting the quality of obtained samples were studied in [9, 10] and can be divided, following [9], into thermal (e.g., high heating rates, high local and macroscopic temperature gradients) and athermal ones (e.g., electromigration, electroplasticity, dielectric breakdown, etc.).
One of the important factors is the Joule heating.
The simulations showed that the increase of hs by factors of 2 and 4 leads to the change of the average sample temperature from 519oC to 567 and 656oC correspondingly.
Cverna (ed.), ASM Ready Reference: Thermal properties of metals, ASM International, 2002, 560p

However, localization of the initiation sites on the surface affects not only the polymerization kinetics, but also determines to a remarkable extent the chemical composition, structure and the physical properties of the resulting polymers.
This in turn determines the overall properties of the heterogeneous polymer system.
The results of investigating the influence of various factors on the molecular weight (MW) of polymers obtained (Table 2) have shown that the polymer MW and, correspondingly, degree of polymerization (DP) decrease with increasing temperature and increasing [I], which is typical to free-radical polymerization.
Influence of various factors on the molecular weight of the resulting polymers.
It has been established that the pigment surface participates not only in chain transfer reactions, but also affects all other elementary stages of polymerization.

Influence of the Source and Sink Temperatures on the Experimental Research of a CO2 Trans-critical Refrigeration and Heat Pump System ZHANG Wen-hui1,a, WANG Zhe*1,a, GONG Yi, WU Xue-hong, LU Yan-li *1Department of Electrical and Mechanical Engineering, Refrigeration and Cryogenic Center, Zhengzhou University of Light Industry, Henan, Zhengzhou, No. 5 Dongfeng Road, 450002, P.R.China *ae-mail: zhezhenature@gmail.com Keywords: The source temperatures, The sink temperatures, CO2 trans-critical cycle, Heat pump, Refrigeration, Experimental study Abstract: The performance of the CO2 trans-critical system is affected significantly not only by optimal system pressure but also by instantaneous ambient temperatures.
It is a natural refrigerant, non-toxic, odorless, non-flammable, environmentally friendly and excellent thermal properties, known as "a nearly ideal refrigerant" [3].
The CO2 enter the intermediate heat exchanger is not a high temperature and pressure of liquid but the mixture of liquid and supercritical fluid, which will affect the trans-critical CO2 refrigeration cycle performance.
Experimental Determination and Analysis Thermodynamic analysis of the system, the energy efficiency of trans-critical CO2 refrigeration and heat pump system by the gas cooler outlet temperature, pressure and other factors [9-10], which variables are relatively independent in the supercritical region, so the design for the experimental independent variables.
This is because the heat source temperature affects the water in the evaporator inlet temperature, the temperature of the water circulation system as a whole rise and the temperature trend.

The bending angle depends on the input laser energy, the speed at which it traverses the sample width, as well as the mechanical and thermal properties of the material.
Experimental A series of test samples 200mm in length, 60mm in width and 8mm in thickness were cut from standard stock hot rolled mild steel flat bar (material composition and mechanical properties given in Table 1).
C Mn P S Si Al Chemical composition 0.22 max 1.6 max 0.04 max 0.05 max 0.5 max 0.1 Tensile Strength [MPa] Yield Strength [MPa] Hardness HV50 Elongation % Mechanical properties 450 (min) to 620 (max) Actual 300 (min) Actual Actual (160) 20 Table 2.
Through-thickness mapping of the microstructure indicates the cusp of the heat affected zone (HAZ) to be limited to the width of the laser beam [5].
This also creates conditions for dynamic recrystallization which in combination with phase transformation are the key factors leading to grain refinement.

Creep modeling for Concrete Filled Steel Tubular members compressed with a large eccentricity Han Bing1, a, Wang Qian1, Wang Yuan-feng1, 1School of Civil Engineering, Beijing Jiaotong University Beijing 100044 aemail: bhan@bjtu.edu.cn Keywords: concrete-filled steel tubes; creep; large eccentricity; model B3 Abstract：Based on concrete creep calculation model B3 and mechanical characteristics of concrete-filled steel tube (CFT) beam-column members of large eccentricity, a creep calculation model of CFT beam-column members of large eccentricity is constructed, which accords with mechanisms of concrete creep, and creep characteristics of concrete core of CFT beam-column members of large eccentricity have been taken into account.
Qi studied mechanical behaviors of circular CFT members under long-term load and creep experiments of circular CFT beam-columns were carried out during 1983~1984[7].
However, just a few factors were involved in the equation, so that the method could not be spread widely.
The detailed calculation process is as follows: (1) The member is discretized, geometric properties are constructed, and depth of neutral axis and curvature are assumed
Conclusion From the analysis and calculation results presented in the paper, several conclusions are drawn as follows: (1) From plenty of creep curves shown in the paper, we see that CFT creep develops quickly at the beginning, 80% of which in five and half years is accomplished within the first 500 days, while after that, creep curves still trends upwards but much slower than before; (2) Among all factors that affect CFT creep, internal factors, such as water to cement ratio and aggregate to cement ratio, do not play a leading role; however, it’s the external factors that are dominant in creep parametric analysis, among which steel ratio and axial load seem to have the greatest effect on CFT creep shown from the previous study.

The material properties of the workpiece were employed from the built-in database of material properties in simufact.forming ver. 14.0.1.
The shear friction factor along the hollow part of the upper die was varied in the range 0.1 ≤ mb1 ≤ 1.0, while the shear friction factors at the other parts of the upper and lower dies were assumed to be mb2 = mf = 0.4.
Thus the extruded lengths, especially the backward extruded length, are found to be affected by the friction.
From the above results, it is confirmed that the workpiece flow and the forging load are affected by the friction conditions along the hollow part of the upper die.
Groche, Mechanical servo press technology for metal forming, CIRP Annals – Manufacturing Technology, 60-2 (2011) 651-672

This importance of polymeric materials at the same time demands an efficient joining technique without compromising their properties.
Joining techniques for polymers include adhesive joining, mechanical fastening, hot plate, ultrasonic, laser, vibration, spin and friction stir welding.
Kiss [9] developed a relationship between a factor “K” and HAZ seam.
Czigány, "Effect of welding parameters on the heat affected zone and the mechanical properties of friction stir welded poly(ethylene-terephthalate-glycol)," Journal of Applied Polymer Science, vol. 125, pp. 2231-2238, 2012
Doniavi, "An experimental study on mechanical properties of friction stir welded ABS sheets," Materials & Design, vol. 43, pp. 402-409, 1// 2013

Introduction It is well known that the mechanical properties of a granular material are governed by various factors such as the characteristics of its constituent particles and conditions of deposition.
Assemblies of circular particles were satisfactory for this purpose as they do exhibit most properties of granular materials qualitatively, such as strain softening, volume increase, and the transition to a critical state at a large strain.
On the other hand, their strength is low and their deformation properties are quantitatively far too different compared to real granular materials.
Influence of Particle Shape on Engineering Properties of Assemblies of Two-Dimensional Polygon-Shaped Particles, Géotechnique, 2002, 52 (3), 209-217
Initial Fabrics and Their Relations to Mechanical Properties of Granular Material, Soils and Foundations, 1972, 12, 1, 17-36