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Although each batch was prepared in the same manner and the specimens were cured in the same way, the matrix mechanical properties obtained are slightly different.
On the other hand, it appears that the different mechanical properties of the matrix batches employed did not affect the load responses.
This evidence suggests that the inherent bond between matrix and fibre, rather than the mechanical properties of the matrix, plays the fundamental role in determining the load-carrying capacity of FRCM-concrete joints [14].
The different mechanical characteristics of the matrix did not appear to affect the load responses.
[17] ASTM INTERNATIONAL, “Standard test method for tensile properties of polymer matrix composite materials”, ASTM D3039/D3039M-08, West Conshohocken, USA, 2008

Physical Phenomena of Thermoplastic Articles in the Vicinity of Their Glass Transition Temperatures Sam Kharchenko and Jack Huang Masco Corporation OTS-R&D, 7500 Holland Road, Taylor, Michigan 48180, USA skharchenko@masco-rd.com, jhuang@masco-rd.com Keywords: Environmental Factor, Thermoplastic, Glass Transition Temperature, Heat History, Thermal Cycle, Dimensional Stability, Residual Stress, Coefficient of Thermal Expansion, Deformation.
Introduction When choosing thermoplastic material for an application, often the focus is on mechanical properties, processing conditions, and costs.
While analytical models for the prediction of the bowing and the warping due to temperature gradients have already been developed [1, 2] and many studies have tackled these physical phenomena in great detail [3-5], we seek to understand how periodic temperature gradients affect the dimensional stability of thermoplastic articles, especially when temperature reaches the vicinity of their glass transitions.
To understand & separate the effects on dimensional changes from various factors, we first evaluated the extent of process-induced stresses by measuring a sample's shrinkage in the longitudinal direction when the sample was subjected to periodic uniform heating in the oven (Fig. 2).

The effect of PLA:PBS ratio on properties of blend foams as well as the effect of AC on properties of composite foams were investigated such as foam morphology, density, void fraction, crystallinity, and thermal and mechanical properties.
Thermal analysis of foams Crystallinity is an important parameter affecting the foaming process.
Mechanical properties The mechanical properties of foam samples are shown in Figure 4.
Foam samples with no AC particles showed more uniform cell morphologies and higher mechanical properties in case of PLA-rich samples.
Li, Mechanical properties of PLA/PBS foamed composites reinforced by organophilic montmorillonite, Journal of Applied Polymer Science. 131 (2014) 40773-40780

The joint characterization program consisted in the assessment of welded joints creep properties.
Mechanical and creep properties of weldments were measured both in the as welded and post weld heat treated conditions and proper WPS's were designed in a manner such that industrial production needs were satisfied.
Accordingly, welding techniques are highly needed for joining these materials with comparable high temperature properties [2].
Mechanical properties of both grades fulfil the ASTM requirements, Table 2.
The welded joints creep strength, of utmost importance for materials used in high temperature applications, must be assessed in order to obtain safety factors for the design and to ensure safe working conditions of the components.

It is known that the ultra-fine-grained structure in the material has increased physical and mechanical properties, which, in turn, favorably affects the quality of surface layer [4-12].
As a study of the roughness parameters of the machined surface was taken into account the following factors: arithmetical mean deviation of profile Ra µm; root mean square roughness – Rq, µm; the maximum height of the profile Rmax, µm; measured the height of irregularities Rz, µm; average step of roughness – Sm, µm.
R. 2018 Improving the performance properties of titanium alloy on the basis of grinding grain microstructure and surface modification. : dis. ...
Z. 2016 UFG structure and mechanical properties of magnesium alloy MG-1% CA.
Reception, structure and properties M. : Akademkniga.

A Study of Exit-Burr Formation Mechanism Using the Finite Element Method in Micro-Cutting of Aluminum Alloy Dong Lu1,a, Jianfeng Li1,b, Yiming Rong2,c , Jie Sun 1,d, Jun Zhou 1,e and Zhongqiu Wang1,f 1 School of Mechanical Engineering, Shandong University, Jinan, China, 250061 2 Worcester Polytechnic Institute, Worcester, MA, USA, 01609 a ludong80@gmail.com; bljf@sdu.edu.cn; crong@wpi.com; dsunjie@sdu.edu.cn; e zhenzhang@mail.sdu.edu.cn; fzhongqiu.wang@gmail.com Keywords: Micro-cutting, Exit-burr, Formation Mechanism, Finite Element Method Abstract.
Mechanical micro-cutting is capable of fabricating high profile accuracy, surface finish quality at reasonably low cost.
φ φ φ mµ mµ Fig.3 Burr formation stages Simulation Results and Analysis There are some factors affecting burr formation, such as cutting speed, uncut chip thickness, tool edge radius, and workpiece material properties.
The Formation and Properties of Machining Burrs (Logan, Utah State University, 1973).

Properties such as straightness, dimensional stability, unlimited length and interchangeability with unjointed timber make it suitable for the above cited applications.
Several timber-related factors are also known to affect the strength of finger-joints, such as species, density, and natural defects, while others are related to the gluing process.
In order to better understand the mechanical behaviour of timber beams in bending, a non-linear numerical analysis is necessary.
The material properties for Spruce wood are: E1 = 12.7GPa; E2=E3=0.43GPa; n12=n13=0.39; n23 = 0.51; G12=G13=0.73 GPa; G23 = 0.03 GPa; syield = 55 MPa; Q = 0.75 GPa; b=17; F= 0.35; G = 0.4; H = 0.6; L = 1.5; M = 1.5; N = 1.45.
Cohesive zone models (CZM’s) were used to simulate these fractures, whose properties were estimated from literature data.

From the definition and research content, the influencing factors are multi-level and multi-faceted, which leads to use AHP to ensure the set of influencing factors.
Transparency, degree of mixing and mapping way are the indicator to judge the mapping distortion of the picture and polygonal model; (3) Material includes three factors: material’s color of tree-dimensional model, light color of tree-dimensional model and reflective property of tree-dimensional model.
(1) Define the objectives and evaluation factors: assumed there are n indicators,
Experts from different fields affect the degree is not the same evaluation results, so we should consider expert judgment impact factor.
The working conditions for front area in terminals are complex with the addition of the natural factors.

In this paper, the machining strategies for fabrication of die assembly with typical shaped cavity using EDM were discussed, according to the different cavity structures, the best machining strategies were proposed Introduction With the development of material science and industry progress, a large number of high strength, high hardness, high toughness, high brittleness, high temperature and other special properties of the mold material have been applied more and more widely.
Adaptive control is more or less a feedback loop; as information is fed to the controller from the workpiece, the controller is able to change its inputs thus affecting the workpiece.
As the spark melts the workpiece, so too is the tool electrode affected.
Tool electrode a) Rough machining b) Semi-finishing c) Finishing machining d) Schematic plan of machining Fig.6 Machining strategy of fabrication Conclusions The strategies for fabrication of die assembly with typical shaped cavity by using electrical discharge machining are researched, and the following conclusions are drawn. 1) Electrical discharge machining (EDM) method is very suitable for fabrication of hard material with the typical shaped cavity such as deep and narrow slot or freedom surface. 2) The tool electrode wear, especially the corner wear is one of the main factors influence the machining accuracy of machining die assembly using EDM method. 3) Several machining strategies for fabrication of die assembly with typical shaped cavity are discussed.
[4] Zhao Wei, Ren Yanhua, Ren Zhonggen, et al., “Research on the movment law of charged particle in the channel of EDM,” Mechanical Science and Technology, vol. 20(5), pp 762-763

Shield tunnel floating involves many factors,which not only consist the problems of tunnel design itself,such as tunnel linear,the thickness of overburden soil,formation characteristics and surrounding environment.But also consist the problems of construction technology,such as the control of tunnel axis,construction parameters and grouting materials properties etc[2,3,4].
Shield machine works under shallow covering in the bottom of the river, unbalanced forces of the tunnel will cause tunnel floating,and it is difficult to control the tunnel axis.what’s more,it is easy to cause flooding accident due to construction parameters control，which affects construction safety and tunnel forming quality[5].
Figure 1 Plane relation with shield tunnel and Tangjia river The outside diameter of shield tunnel is 6.2m,the inside diameter is 5.5m,the segment lining thickness is 0.35m,the segment ring width is 1.2m,staggered assembling,bolted joint.Shield is mainly through silty sands.Soil main physical and mechanical indexes are shown in Table 1.
Table 1 Soil main physical and mechanical indexes Soil Name Unit Weight （kN/m3） Compression Modulus （MPa） Cohesive Force （kPa） Internal Friction Angle （°） ②1clayey silt with silty clay 18.6 7.9 12 28 ③1sandy silt 19.0 14.38 5.0 31.5 ③2silt 19.0 13.08 1.0 32.5 Calculation of the minimum thickness of overburden soil Shield tunnel across the river and other shallow covering should meet the requirements of the minimum thickness of overburden soil.Simplified calculation analysis method is usually used to calculate the minimum thickness of overburden soil by analyzing force balance of segments buoyancy,the weight of upper soil column and segments weight[5].The minimum thickness of overburden soil calculation diagram is shown in figure 2.
Besides taking anti-floating reinforcement measures, shield construction parameters control is an important guarantee to ensure construction safety.Soil chamber pressure control directly affect the stability of excavation face;grouting pressure size, distribution patterns and slurry characteristics directly affect the size of buoyancy on the tunnel[9,10].Therefore, soil chamber pressure and grouting pressure should be controlled strictly in this project