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They indicated that the resulting surface roughness can be easily influenced by numerous factors such as cutting conditions, environmental, material properties, vibrations and so on.
RSA 443 is a new alloy developed with excellent mechanical properties resulted from the tailored microstructure.
The physical and mechanical properties of RSA 443 are shown in Table 1.
Physical and mechanical properties of RSA 443 alloy.
This indicate that all factors are significant.

This fatal injury greatly affected normal operation and durability of curved beam structure [2].
Engineers hope to improve the mechanical properties by effective means, in order to enhance the durability and prolong the service life of curved girder.
Through study of natural frequency of external prestressing curved beam(controlled by factors of curved girder span, section properties etc.)
There are many factors affecting external prestressing curved beam’s dynamic performance.
Before doing dynamic test, mechanical properties of test material must be determined, such as concrete strength, ultimate strength, tensile strength of strand, and yield strength of non-prestressing reinforcement.

Welding processes used to build large stiffened structures, such as friction stir welding (FSW), are responsible for introducing geometrical imperfections, changing the material properties and adding residual stresses.
These factors can therefore affect the panel’s structural behaviour when subjected to compressive loads.
Numerical models can also account for some factors related to the welding process, not possible to include with analytical methods.
In this area, the influence (on the stiffened panels' strength) of the residual stresses, material properties modifications in the heat affected zone (HAZ) and geometrical distortions have been studied by several authors [1, 3-6].
It is generally accepted that the aforementioned properties mainly depend on the microstructure, the micro-hardness and, on a larger extent, the process induced residual stresses.

Welding Process Optimization for orthotropic compound bridge plates Yongzhi LIa, Fuyi YUb School of Mechanical and Materials Engineering, Jiujiang University, Jiujiang 332005,China a liyonhi168@163.com，b379913698@qq.com Key words : Stainless steel bridge plates; Orthotropic and compound;Welding optimization Abstract: Compound plates of stainless steel is used to weld under construction in the Southern link’s railway bridge for the first time in China, but there occurs weld warpage of the convex parts and roughness appears excessive on the overall composite plate and severe deformation in the early phase of construction and the quality of railway bridge is affected seriously.
The form of V-type and CO2 welding gas arc welding process are used.There have a larger gap ,large welding field strength and too slow to affect the duration because of the site group.
Meanwhile, the early welding test results show that there occur weld warpage of the convex parts and roughness appear excessive on the overall compound plates, some areas of severe deformation, all of which affect the quality of the weld after forming significantly.So in this paper, the welding forming quality is used to scientific analysis and construction program optimization, it is important practical significance.
Welding image of compound bridge plates Process optimization of welding Preliminary studies have shown that there have many factors affecting welding quality of composite bridge plates and this is a very necessary to welding quality assurance.
Improve the quality of manufacturing cells ⑴The cutting material need specification, and heat treatment must be completed,;there need subsequent heat treatment if necessary and control the accuracy of production unit. ⑵ There has a right cutting-groove technology and subsequent heat treatment in order to eliminate stress and improve material properties. ⑶ Transportation, installation, assembly and other process specifications shall be developed , and it will eliminate roughness, control gap and reduce the stress concentration. ⑷ The design innovation riveting bolts。

In order to ensure the mechanical properties and durability of concrete, the setting times of new concrete accelerator is not the shorter the better, the appropriate initial and final setting times are 1min30s~5min and 4min~ 12min respectively.
Prudêncio et al [6] found that the fineness of cement, the species of gypsum, gypsum content and content of C3A are the main factors influencing the traditional accelerator performance by changing the chemical composition of cement, fineness etc.
Liquid alkali-free accelerator is more and more widely applied because of its excellent properties of durability in physics and mechanics, therefore it is very necessary to research its compatibility with cement.
On the base of JC477, appropriately increase the amount of water reducer agents in terms of their types and properties according to the European standard.
In order to ensure the workability, mechanical properties and durability of cement and concrete, setting times of accelerator is not the shorter the better, the appropriate initial and final setting times of accelerators are 1min30s~4min and 4min~10min respectively.

In general, the mechanical material properties are strongly temperature-dependent [15][16].
In the next section, mechanical material properties are presented for the dual-phase steel grade DP600.
The elastic and thermal properties have been taken from [10].
Fig. 2 Plastic material properties obtained from the fit of the stress-strain curves.
Simulations have been performed to give some indications about which factors affect the accuracy of the model.

The result indicated that under the interactions of freeze-thaw and mixed erosive solution, there were not only physical changes but also chemical reactions occurred in concrete, which exacerbate the mechanical properties deterioration of concrete.
Introduction The attack of freeze-thaw is one of the major factors which induce performance deterioration of existing reinforced concrete structures in cold regions.
This indicates that the joint function of the erosion solution contains sodium sulfate and sodium chloride and the freeze-thaw affected the concrete surface sapling significantly.
a) 3%NaCl+5%NaSO4 b) 3%NaCl+1.5%NaSO4 c) 5%NaSO4 d) water Fig. 3 Micro-structure of concrete in different solution after 100 circles of freeze-thaw Analysis of deterioration mechanism After the alternative effect of immersion in mixed solution and freeze-thaw cycle, there are microstructure changes the mechanical property degradation in concrete.
Chemical and physical change influenced and affected each other, and leaded to different levels of concrete deterioration in different mixed erosion solutions.

The main research of this test is the influence of different water pressure, water jet forward speed and target distance factors in forming process.
In this test, using DWJ-A/B series CNC universal water jet cutting machine shown in Fig. 1, made in DARDI Company in Nanjing, process out of the five long grooves, calculate the average of the five long grooves depths and observe the surface quality of sheet metal influenced by different combination of factors.
The chemical composition and mechanical properties of the copper as shown in Table 1 [4]: Table1.
Chemical composition and mechanical properties name Trademark Cu+Ag Pb σ/MPa δ/% Pure copper T2 99.90 0.005 205 30 Selecting a group of test methods and building a finite element model by mechanical analyzing and simplifying.
However, due to the sheet metal under pressure to bend, the object which sticking in the sheet also generated curved which cause bending moment affecting the simulation results.

They affect spell near joint processing quality.
Experimental tool path design Considering the factors of statistics, between of A and B two blocks respectively, B and C for a group of the same between two blocks of the milling test.
(1) From the calculated values ​​in Table 1 and Table 2, it can be seen milling force change is the main factor affecting the surface topography
Journal of Mechanical Engineering,2000,36(3):13-16
Environmental variability of modal properties[J]．

The mechanical properties were determined by a texture analyzer.
The mechanical properties of the MNs were evaluated using a texture analyzer (TA.
Results and Discussion Physical appearance and mechanical properties.
The mechanical properties of MNs can be affected by polymer type or concentration [6].
Neonatal porcine skin was used to insert MNs because its mechanical and structure properties were similar to human skin [8].