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In the test, the deformation properties of composite shear walls and the development law of the strain of concrete and steel were studied.
The research production has provided a foundation for the further exploration to the working properties of the composite shear wall under cyclic loading.
The key to ensure this kind of composite wall to work well is to have a good interface bonding properties between the composite cement slabs and concrete.
Although they both belong to cement-based materials, which are similar on the basic physical and mechanical properties and with good adhesion basis, but as the interfacial bonding properties are affected by a variety of factors, such as the interface conditions, the quality of the concrete pouring, and the force status, the uncertainty whether composite cement board and the concrete can work together well is brought by those factors.
Firstly, the development rule of the overall deformation properties of the composite shear wall and the strain properties of each part of the wall was studied[6-7].

Even in defectless products, internal stresses negatively affect their properties; in particular, they reduce ductility.
Mechanical properties.
Increasing the annealing time from 90 to 180 min did not bring any change in the mechanical properties.
Table 3 Average values of mechanical properties for different annealing times.
Longer annealing did not alter the mechanical properties anymore.

Owing to lots of closure segments, there are many influencing factors on closure schemes.
A appropriate closure scheme could be promoted by summarizing related information, clearing the stress mechanism, analyzing correlative factors in FE method, compared the healthy monitoring data, and combining with the statistical data of closure schemes obtained from other domestic practical projects.
For this multi-span prestressed concrete box-girder bridge, there are three symmetrical closure sequences affecting the structure stress: - the side span firstly, then side span and middle span at last; - the side span firstly, then middle span and the second side span at last; - middle span firstly, then second side span and side span at last.
After the structure stress and deformation in the finished bridge state under three different closure sequence have been analyzed comparatively, the mechanical properties of box-girder have no significant effect in three different closure sequence under permanent action, while it is different on pier, then the stress of pier in sequence Ⅰ is the most uniform, and the variable range of stress is minimum.
Fig.10 Calculation diagram of Sanbazhou Bridge During the research, the mechanical properties at two state that finished bridge state and 5 years after finished bridge are compared, it is found that bridge displacement is the most uniform in all span in sequence 1, the value is littler than it in sequence 2, displacement increment in sequence 2 for 5 years in 4 mid-spans is less than 5%~18% in sequence 1. thus, displacement of girder is more reasonable in closured sequence 2(side-span firstly, mid-span secondly) (Fig. 11, Fig. 12 and Fig. 13).

The key factors involved in the train derailment on bridges or lines have been discussed in this paper.
Mechanical mechanism of train derailment.
The mechanical mechanism of train derailment on railway bridges has been discussed in detail in [10].
Under its influence, the Baoji Railway Station train delays, about more than 1300 passengers affected.
[2] Grob J, Dynamics property of train after derailment, J.Bauingenieur, 68 (1993)501-507

Buildup of model l The establishment of the fuzzy evaluation model.Fuzzy evaluation involves three main factors：(1)Evaluation factors set U=｛u1,u2,…,un｝, a collection of N kinds of factors of evaluation objects.(2)Comment set V=｛v1,v2,…,vm｝, the various factors of the M kinds of evaluation results of collections.(3)The single factor evaluation r ,To get the corresponding evaluation set V( ri1,ri2,…,rim) ,each of the factors is judged Respectively.
l The establishment of the evaluation factor set.There are many factors affecting the pipeline tube, The influence of various factors on the tube is not independent of each other, on the contrary,it is interrelated.
It Is often a result of the combined actions of multiple factors.Therefore, it is very important to select reasonable evaluation factors.Combined with actual situation, ultimately,we choose six factors ,concluding pipe material (M), pipe diameter(C),laying depth(D), pipe age(L), soil conditions(S), hydraulic pressure(P),as the contestant factor setting up the assembly of evaluation factors.
Factor score are between 1-5, and the higher the score is, the more easily to broke tube ,and the lower the score is, the more securer the pipe is.(1)Score of different pipes.According to the analysis of different pipe material properties, under the same condition, the probability of tubing pipe explosion from high to low is: grey cast-iron pipe> nodular cast iron pip> galvanized pipe> steel tube and pipe> plastic pipe.
For qualitative factors, such as soil conditions, pipe material, expert scoring method is used to determine its membership degree.for quantitative factors, such as pipe diameter, water pressure, pipe material, membership function is used to determine the membership degree.

The failure causes include various factors, the same fault symptom, often cause by many different reasons, and the same kind of reason, often can cause different faults.
In normal conditions, it can cause the rolling bearing different forms of damage, ultimately cause the functional deterioration if the machines are overloaded, lubrication is poor or other factors.
In normal state, the bearing rotation will produce a normal vibration that relate to the elastic properties of the bearing.
When bearing produce abnormal vibration, the reason most possibly is rolling bearing surface in poor condition and other factors.
Wavelet analysis [9,10] can analyze the time domain and frequency domain properties of the signal at the same time, so, it can use wavelet analysis technique to complete the transformation of collected signal.

As indicated in electroforming test of metallic nickel, in comparison with traditional electroforming technology, particle flow erosion precision electroforming technology can effectively change the microscopic structure of electroforming deposit, refine grain and realize evener distribution of grains, so as to reduce the diffracted intensity of all crystal faces and enhance mechanical property of electroforming deposit.
With adoption of electroforming technology, it is possible to duplicate products of abnormal structure and components difficult to process or fabricate by mechanical method.
In accordance with Hall-Petch principle of common poly-crystal metal material sub-grain strengthening theory, performance of material is closely related to grain size and densification degree, its comprehensive mechanical property and grain size normally comply with the Hall-Petch relationship: ——proof stress of material ——lattice friction in case of single dislocation caused by movement —— constant d ——crystal grain size Microhardness HV Figure 7 A micro-hardness comparison diagram of two groups of test The comprehensive mechanical property of material is inversely proportional to the extraction of grain size d.
Particle flow erosion precision electroforming technology has expanded the application field of precision electroforming, and plays an important role for enhancement of comprehensive mechanical property of electroforming deposit.
Study on New Electroforming Technology of Abrasive Hard Particles, China Mechanical Engineering. 2006, 17 (1): 60-63

There were many researches about the mechanical properties of artificially frozen soil [1-3], but the numerical simulation and interaction of frozen soil and derrick has not yet mature.
The maximum calculated bending stress of the derrick was 214MPa, the safety factor reached to1.16 or more.
Affected by the frost - heaving, the maximum value of the concrete strain gauge B313 reached to 390με, for it was near the frozen wall.
Summary Affected by the frost - heaving, the pressure box Y44 and Y46 had a greater increase, for it was near the frozen wall.
But later the pressure values begun to decrease affected by the deformation of frozen soil.

However, it is commonly believed that the fracture toughness is affected by the constraint effects.
The parameters α and k are dependent on the material properties and the fracture mechanism.
The GCF and T11-stress are affected by the size and integrity of the stiffeners.
It can be seen from Fig. 4 (a) that the size and integrity of the stiffeners have important influences on fracture toughness, the reason can be explained by the fact that T11-stress is dependent on these factors.
Dai, Crack arrest behavior of central-cracked stiffened plates under uniform tensions, International Journal of Mechanical Sciences, 133 (2017) 704-719

Ultraviolet light has been considered a main factor of natural aging threats the oil sealing’s lifetime when using outdoor.
The good performance of oil resistant, stability of the other corrosive medium, superior mechanical properties and the easy processing makes NBR can be widely used for seal.
In the article [1], the author studied the mechanical properties under the different temperature and aging time.
And establish the relationship between aging factor, aging time and temperature.
Nitrile rubber during the processing, storage and use process, especially when used outdoor, will be affected by environmental factors such as light, oxygen and heat.