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Superior mechanical performance makes it widely used in the bridge practical engineering.
Based on the past research, this paper studied the impact factors of constant load, temperature load and live load under different structural systems, in order to analyze the structure performance for different structure system of extra-dosed cable-stayed bridge.
In order to compare the mechanical characteristics of the three structural system, the full-bridge three-dimensional finite element models of the three structural systems were established with the same material, section properties, cable arrangements, load cases and supporting forms, which differ only in the simulation of the different connections among the pylon, girder and pier.
Summary The common forms of the support of the extra-dosed cable-stayed bridge include semi-floating system, pylon-girder consolidation system and rigid-frame system, which have their different mechanical response and their own advantages and disadvantages.
The loading of temperature change does not affect the pylon-girder consolidation system.

Expansion property is of great significance to engineering.
On the one hand, expansion rock has strong expansion performance, when it is disturbed by something, especially by water, its properties will change dramatically and its volume increases.
China is one of the countries with most widely distributed expansion rock in the world, because of the special engineering properties, research on expansion rock and its engineering disaster has important significance to engineering [1-3].
In fact, water has physical, chemical and mechanical effect on rocks.
The constitutive equation of rock considering humidity field For humidity field loading problems, constitutive relation affected by humidity, elastoplastic and other factors should be taken into consideration.

In addition, as in the case of conventional materials, the stress/strain amplitudes, surface roughness and thermomechanical history are the other factors that govern the fatigue life of SMAs.
This is because, unlike most engineering materials, the properties of SMAs are very sensitive to slight variation in composition, microstructure, thermo-mechanical history and even experimental conditions.
Functional fatigue tests usually refer to complete or partial TC / TMC for evaluating the change in functional properties.
The transformation temperatures (TTs) and mechanical properties of the annealed wire in the martensite phase are given in Table 1.
Results Variation in Functional Properties on TMC.

This paper aims to find out the key risk factors existing in the oil pipeline as followed: corrosion, machinery and material failure, the third-party damage and maloperation.
Building the Fault Tree of Refined Oil Pipeline The fault tree of refined oil pipeline takes the pipeline failure as the top event, which is the main factor affecting the stability of the refined oil pipeline.
landslide 29 30 31 32 33 34 35 Pipeline material and design security system is unsatisfactory Wrong   rules and regulations Social relationship status safety equipment failure Operation personnel competence operating supervision 36 37 38 39 40 41 42 Lack of corresponding instruction Lack of elementary knowledge Lack of emergency exercise welding material quality maintenance management lack of training plan maintenance equipment 43 44 45 46 47 48 49 Lack of strict tests for mastery knowledge Maintenance personnel responsibility senses thickness of Anticorrosion insulation coating bond force of Insulating anticorrosive coating Fragility of Insulating anticorrosive coating breakage in Insulating anticorrosive coating Wrong position operating procedure 50 51 52 53 54 55 56 lack Pipeline safety education selection of welding methods Insulating anticorrosive coating aging pretreatment conditions of Welding surface Existing gas in welding surface Length of Not welding parts weak public moral property
awareness 57 58 59 60 61 62 63 anti-corrosive pipeline material is not up to standard filled soil contains corrosion material cleaning of welded surfaces Economic development along pipelines internal coating thickness diameter of filled soil particles filled soil water ratio 64 65 66 67 68 69 70 pipe trench drainability Existing crack on pipeline Pipe defect pipe joint electric current disturbance cathodic protection failure amount of bacteria in soil 71 72 73 74 75 76 77 The depth of pipe drain soil water content Soil sulfide content soil redox potential soil salinity mechanical damage corrosion detection 78 79 80 81 82 83 84 Remaining stress slope stability buffered etch failure cleaning efficiency process quality Construction supervision piping material Table 2 Intermediate Events in Fault Tree of Refined Oil Pipeline A B C D E F Third party activity corrosion cracking natural disaster Operational illegal construction stealing oil from borehole G H I J K L pipeline extrusion Stress
Corrosion operating misoperation maintenance misoperation construction misoperation legal factor M N O P Q R line-cruising agricultural activities public education exterior activities acid medium tensile stress S T U V W X the man-made misoperation construction defects special medium Corrosion staff training drainage construction anticorrosion and insulation layer Y Z A1 B1 C1 D1 pipeline welding pipeline installation corrosion internal corrosion external corrosion anticorrosion measures E1 F1 G1 H1 I1 J1 anticorrosion and insulation layer decreased initial imperfection anticorrosion and insulation layer decreased in operation existing defects unqualified pipes construction defect Fig 1 Fault Tree of Refined Oil Pipeline Fig 2 Continued Fig 1 The structure importance sequence of the fault tree Analysis of Fault Tree of Refined Oil Pipeline Basic understanding of the FTA.

The paper presents erosion properties of some stainless steels, several cast iron and cast steel using a blast type high temperature erosion furnace.
Erosion factors are kinetic energy, mass, hardness and shapes of erodent, and so on.
In addition to these erosion factors, as for the high temperature erosion, microstructure of material influenced by heat and whether there occurring high temperature oxidation or not, are becoming important wear factors that don't need to consider at room temperature [8-10].
In other words, the high temperature effect the mechanical property such as hardness or elongation of materials, and differences of erosion rate for specimens are likely to be related to hardness and elongation at elevated temperature.
The design of material with excellent erosion resistance, under high temperature region, will require an understanding of how the properties of materials are affected by elevated temperature and how high temperature oxidation is limited by adjustment of chemical composition of material.

The present modified SIMA process was discussed as an alternative thermo-mechanical processing for preparing the alloys with fine grained structure for semi solid processing.
The fine solid spheroids, not necessarily one grain per a spheroid, ensure the better rheological properties by lowering the flow resistance of semi-solid.
Effect of RAP Temperature For semi-solid processing, the insufficient amount of liquid deteriorates the rheological properties of semi-solid, and contrarily its solid-like behavior is lost by excessive liquid fraction [7].
Σε = 0), the 620°C 630°C 635°C 250°C 200°C recrystallized grain size was not affected by the RAP temperature (Fig. 5a) and remained as ∼200 µm at all RAP temperatures (Fig. 6).
However, the multi-forging temperature did not affect the recrystallized grain size.

The second one is that the spread velocity of Rayleigh wave has a close relationship with physical mechanics property of media [4].
Table 1 Stratum structure of inversion C5G Property Layer Shear velocity m/s Bottom depth of the layer /m Layer thickness /m ① 139.2 0.7 0.7 ② 158.0 2.1 1.4 ③ 164.6 5.1 3.0 ④ 346.7 10.1 5.0 ⑤ 641.5 15.3 5.2 Bedrock 848.1 -- -- Because the thickness of ② and ③ have the approximate value, nearly no difference, we can regard the two layers as one layer, so the final result is in Table 2.
Table 2 Stratum structure after merging Property Layer Shear velocity m/s Bottom depth of the layer /m Layer thickness /m ① 139.2 0.7 0.7 ② 164.6 5.1 4.4 ③ 346.7 10.1 5.0 ④ 641.5 15.3 5.2 Bedrock 848.1 -- -- To verify the veracity of Rayleigh wave exploration, we compare the result of Rayleigh wave exploration with the field bore histogram, as is in Table 3.
Rock core mainly presents fragmental structure; easy to softening disintegration after soaking, mechanical strength is low and inhomogeneous, ability to resist weathering is low, belongs to extremely soft rock, crushed rock mass, fundamental quality level is Ⅴ. ⑤ K2p 14.8 3.5 Argillaceous siltstone: purple, red, slightly claybank, partial rock mass has broke, weathering fractures are obvious, rock core mainly presents short-medium column structure, rock strength is higher than that of intensely weathered zone, belongs to soft rock, rock mass is intact, fundamental quality level is Ⅳ.
Chinese Journal of Engineering Geophysics. 2013.01 [3] Jianjun Niu, Xiaopei Zhang, Lizhi Du, et al: Research on the factors affecting the precision of transient Rayleigh wave exploration (In Chinese).

Modal Analysis of Stator and Rotor in Large Capacity Permanent Magnet Motor Shenbo Yu 1, a, Lei Li 1,b , Shen Cao 1,c 1School of Mechanical Engineering, Shenyang University of Technology, Shenyang, P.
These factors determine the modulus of elasticity of winding.
Property of each material can be determined.
Fig.2 Order 1 mode shape (lamination) Fig.1 Order 1 mode shape (entity) The winding affect model of large motor stator.
It means that natural frequencies of rotor are hardly affected by the magnets.

In a molecular dynamics (MD) simulation, grain size and crystal orientation can be chosen, and their effects on the mechanical properties of nano-crystalline materials can be evaluated clearly.
Introduction In recent years, various polycrystalline metals with nano-scaled grains have been developed, and their detailed properties are being evaluated[1-5].
However, the effects of grain size in the very small grain range on the mechanical properties, especially fracture mechanism, are not fully clarified.
However, we think that the indicated errors do not significantly affect the crack growth behavior.
Therefore, the crack opening and extension are affected by the grain size.

Petrov1,c and K.Verbeken1,d 1Department of Materials Science and Engineering, Ghent University (UGent), Technologiepark 903, B-9052 Ghent, Belgium a aurelie.laureys@ugent.be, b tom.depover@ugent.be, c roumen.petrov@ugent.be, d kim.verbeken@ugent.be Keywords: TRIP, Hydrogen embrittlement, mechanical properties, tensile tests, hydrogen induced cracking, EBSD, crystallography, SEM Abstract.
The goal of this work is to understand the response of the hydrogen saturated multiphase structure to a mechanical load.
Introduction Hydrogen introduction into steels is often correlated to a degradation of mechanical properties, especially loss of ductility [1].
The retained austenite transforms to martensite under external load, which results in an excellent combination of properties, such as high tensile strength, high ductility and good fracture toughness [4].
In mechanical terms, such a notch or crack is described by a local stress and strain field ahead of its tip.