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Across to the Highway Bridge Besign General Specification which is published in 1989, for all kinds of loads, we need consider different safety factor, and consider two kinds of state, which are serviceability limit states and ultimate limit states the loads combination (Table 1) [3].
The Analysis of Disease Factors The cross-section stress state of the prestressed concrete continuous girder bridge reflects the force state of the bridge in the operation process.
We use positive stress and main stress to show the concrete state, which refer to two main factors--the original bridge stress and the loss of the steel prestress.
So the web inclined cracks and baseboard cracks develop and expand quickly, as so as cross-section stiffness and the trend of mid-span center cross-section deflect acutely, which will affect the structure durability.
Conclusions We build the FuFeng bridge reinforcement model in this article, analyze the original bridge state in operation, the mechanical property before and after reinforcement, prove simulation analysis accuracy and reliability.

EMD method based on local features adaptive signal decomposition, overcome the traditional method using meaningless harmonic component to represent the defects of nonstationary and nonlinear properties.
These additional noise signal mixed in the midst of vibration signal, affected the tower drum vibration signal processing and analysis of results.
Figure 4.1 The lateral vibration signal The actual situation is the combined effect of several factors, such as wind load, dynamic load, etc.
EMD method based on local features adaptive signal decomposition, overcome the traditional method using meaningless harmonic component to represent the defects of nonstationary and nonlinear properties.
[5] Jian Hong Yang,Jin Wu Xu,De Bin Yang,et al.Based on the mainstream shape recognition Nonlinear time series noise reduction method and its application in fault diagnosis [J].Chinese Journal Of Mechanical Engineering,2006,42(8):154-158.

Research on Over-ground Electromagnetic Inspection Technique for Buried Pipelines Shuanghao Lu1, a, Zandong Han1,b, Weibin Wang2,c and Zhanjun Feng 2,d 1Dept of Mechanical Engineering, Tsinghua University, Beijing, 100084, China 2Petrochina Pipeline R&D Center, Langfang, 065000, China alush06@mails.tsinghua.edu.cn, bhanzd@tsinghua.edu.cn, cwangweibin@petrochina.com.cn, dkjfengzj@petrochina.com.cn Keywords: Over-ground inspection, Low frequency AC magnetic field, Weak magnetic field detection, Defect recognition Abstract.
Compared with the analog multiplier, the AD630 is not affected by the amplitude of reference signals, and the dynamic range is much more extended.
Considering both factors, a cut-off frequency of 0.48Hz is chosen to balance detection speed and detection accuracy in this paper.
The detection of a pipeline The properties of two defects inspected in the experiments are listed in Table 1.
The properties of defects Defect number Profile of defects Length[mm] Depth[mm] Width[mm] Defect 1# 7.12 1.60 8.10 Defect 2# 4.76 2.20 14.36 To evaluate the distortions of defects, the magnetic inductions that measured are normalized.

Introduction Using fly ash partially replace ordinary Portland cement in concrete can not only lower the concrete economic cost, but also improve lots of working properties and durability behaviors, such as concrete impermeability, freeze-thaw resistance, steel bar corrosion resistance and alkali-aggregate resistance etc[1-5], but at the same time it also can reduce the concrete carbonation resistance[6-7].
Curing quality is the foundation of binder putting into effect, which not only determines concrete mechanical properties but also durability.
Curing temperature, curing humidity and curing time are three important factors influencing concrete curing.
In order to find out the reason of FA concrete carbonation resistance affected by initial curing conditions, FA-cement paste specimens were made, cured and placed according to the same conditions listed in Table 3, then the hydration degrees of FA were measured through “the selective dissolution method”[8].

Introduction Theory and methods to optimize the design of the in-depth and wide range of applications in the design of mechanical structures .
"Birth and death" control unit stiffness matrix is multiplied by astiffness factor, which is the relationship between nodeforces and node displacements of pruning.
Therefore, the structure of each unit can live or die freely, if you want to achieve the goal that unit dies, the program just needs to set the stiffness factor in front of the unit to 0and loads linked to the "dead" unit (concentrated force ,uniform force, initial stress or temperature loads), quality, damping, specific heat and other similar effects and so on all set to 0, instead of really removing "dead "unit .Similarly, when the unit need to "live", the unit does not need to be added to the model, just re-activate the stiffness factor in front of the unit by setting it to 1, at the same time, all loads and some other properties linked to the unit should be activated. 2.2 Modeling method of life and death The process of life and death and other analytical techniques are basically the same, but each element must be considered activate or death.
Overall structural stiffness equivalent to the maximum and minimum strain energy, so in the optimization process, delete an element, a small impact on the total strain energy, so that the weight of the structure can affect the structural rigidity of the largely reduced small. 3.2.

To separate particles in a medium, the attractive van der Waals force must be overcome, which can be achieved by mechanical action and/or chemical additives [3-4].
Among several factors controlling particle dispersion in a suspension, properties of a polymeric dispersant including concentration and MW are ones of the most important.
The variation of dispersant concentration affects surface coverage of particles leading to the difference in their dispersion state and stability [17].
These studies demonstrated that the molecular length of dispersant is an important factor dictating the dispersion state of suspensions.

Gutowski [3] provided the specific electricity requirements for a wide range of manufacturing processes, showed that the rate of production was the most important factor that affected the energy consumption of a process.
The power of FECUs is determined by machine tool properties and can be attained from machine tool manufacturer or measured through empirical studies.
The power of VECUs is determined not only by the machine tool but also other factors such as process parameters and workpiece material, it can be calculated based on existing knowledge and/or appropriate mathematical formulas.
(2001) [9] Li, W., Kara, S.: An Empirical Model for Predicting Energy Consumption of Manufacturing Processes: A Case of Turning Process, in: Proceedings of the Institution of Mechanical Engineers, Part B, Journal of Engineering Manufacture. (2010)

The electrical and thermal properties of rGO are inferior to graphene.
It has been investigated that the graphene oxide and rGO has better optical, mechanical, thermal, catalytic and electrical properties [6, 7].
The NO2 gas sensing properties have been studied using a static gas sensing system.
Tian, Nonlinear optical properties of graphene oxide in nanosecond and picosecond regimes, Appl.
Kim, “An investigation of the electrical transport properties of graphene-oxide thin films,” Mater.

The numerical investigations of masonry under different types of stress are carried out using mathematical models which consider the different properties of masonry as a structural material.
Materials and Methods An experimental study of the mechanical properties of bricks, mortars and their contact interaction as well as diagonally loaded masonry wallets was carried out.
However, making this statement in a generalised way is not correct since the properties of the brick (R1) influence the adhesive behaviour of the samples.
Their use simplifies the process of defining materials and contact properties for FE microstructural analysis of masonry.
Trufanov, Numerical analysis of the effective elastic properties of masonry material (in Russian), Mech.

The engineering properties investigated include the volumetric, dynamic creep, indirect tensile strength, and resilient modulus.
Thus, by considering the engineering, environmental, and economic factors, further research should be conducted on the use of agricultural waste as coarse aggregate replacement in asphalt concrete.
Hence, asphalt concrete incorporating CS insignificantly affects the performance of a mixture because the void is too high.
The application of CS as the coarse portion of aggregates in asphalt conrete mixtures leads to lower rut depth because of the superior interlocking properties and aggregate-binder adhesion exhibited by CS aggregates; these properties increase the ability of asphalt mixes.
Kalurkar: IOSR Journal of Mechanical and Civil Engineering (2014), p. 61-64