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In order to test the quality of the overall structure of the bridge, understand the dynamic characteristics of the bridge structure, and evaluate the mechanical properties and work behaviors of the structure, load tests on the bridge were conducted.
Determination of Test Load To ensure the test results, we take the efficiency of static load test, denoted as ηq, as controlling factors when choosing the load and position of the test, according to the provisions and requirements in "Test Method for Large-span Concrete Bridges”.
As Table 2 shown, the load efficiencies under various working conditions which are maximum bending moment positive at vault, maximum bending moment negative and maximum horizontal thrust at springing, and maximum bending moment positive and maximum bending moment negative at L/4 all meet the requirement which ranges from 0.85 to 1.05, therefore, this load test can reflect the mechanical properties of the structure under the standard vehicle loads on the section of the vault, L/4 and the springing.
It indicates that bridge keeps in good elastic behavior, good mechanical characteristics and elastic resilience state under every case.
Conclusion Determining the declination extent and function of the bridge structure not only helps us to have a total grasp of the existing bridge to ensure traffic bearing capacity safety, but also provides the data which is helpful to a similar bridge under construction to decrease the probability of generating negative factors, also improve the durability of the bridge to extend the useful period of the bridge.

Introduction Planetary gear vibration and noise are key factors affecting system reliability, service life and operating environment.
This paper aims to propose a multi-body dynamic model of HGPT, with which the modal properties of an example system are predicted and compared with the simulation results from previous lumped-parameter model.
Modal property prediction In this section, modal properties of HPGT are predicted according the parameter listed in Table 1.
Chinese Journal of Mechanical Engineering, 2005, 41(7): 50-55
Journal of Mechanical design, 2002, 38(3): 6-9.

The main role of Nb in flat rolling of low carbon steels is well established: it retards austenite recovery and recrystallization during hot deformation, leading to pancaked microstructures before phase transformation, and as a result, to refined and more homogeneous room temperature microstructures with improved mechanical properties.
This can lead to coarser final product microstructures with impaired mechanical properties, or to the formation of undesired non-equilibrium phases.
Gibbs, A mathematical model to predict the mechanical properties of hot rolled C-Mn and microalloyed steels, ISIJ Int. 32 (1992) 1329-1338
However, the above results indicate that both the nominal Nb in the composition and the reheating temperature may also be important factors regarding growth rate, even if these are not included in the reported models.
Both factors define the balance between Nb in solid solution or in the form of undissolved precipitates.

Introduction The asphalt pavement design method based on elastic layered system reflects the mechanical response of pavement structure to some extent, but due to the complexity and variability of materials’ composition and nature, the impact randomness of environment and load factors, and the quality instability of non-factory construction, it is very difficult for the purely mechanical method to learn the real response of actual pavement structure.
On the other hand, although the long-term performance observation could systematically summarize the performance development in the entire life cycle, it is really a long process which costs lots of manpower, material and financial resources as well as analysis difficulty with many influencing factors.
Zejiao Dong (2009)[8] analyzed influence factors of pavement strain response, and space distribution and schedule variation of three dimensional strains.
In consideration of the affecting factors of axle load conversion, temperature correction, transverse distribution and action time respectively, the corrected action times of the first test part is calculated as follows: Ne=10/3×5.83×120×104=2.332×107 times ∈ (1.2×107, 2.5×107), which belongs to heavy traffic based on design specification.
With no load, it is in a steady mechanical phase.

The incorporation of Bioglass ® powder in zinc phosphate specimens resulted in equal or increased cell attachment and activity for almost all cell lines examined without any apparent impact on mechanical or physicochemical properties of the cement, although this needs further documentation.
Their disadvantages however include solubility, low tensile strength, lack of adhesiveness to tooth structure and no anticariogenic properties [5,6].
The immersion even for 16 days did not result in any brittleness of the modified samples and it seems that the mechanical or physicochemical properties of the cement were not affected.
However these findings need further clarification in future research with mechanical properties testing and solubility assessments. 450 600 750 900 1050 1200 1350 Z PC-0.3 Z PC-0.3 7days Z PC-0.3 16days Reflectance W avenum ber (cm -1) Fig.4.
However immersion in SBF negatively affected cell growth compared to non-immersed specimens.

The experimental program involved testing five different percentages of WSF to fortify UHPC, which were produced to illustrate how WSF affected the rheological properties of UHPC.
Finally, waste steel fibers have been added to the mixture to improve its mechanical properties [10].
Silica fume (SF) is one of the key components used to tailor the properties of UHPC, contributing significantly to its exceptional strength, durability, and resistance to various environmental factors.
Physical Properties of Fine Aggregate.
According to many researchers, the increase in compressive strength could be due to a variety of factors.

According to Thomas et al. [9], the proportion of fibers within a composite material and their lengths are key factors influencing the mechanical performance of short fiber-reinforced polymer composites.
The mechanical properties like tensile, hardness, and impact strength are studied.
Physical and Mechanical Properties of Polyester Matrix S.
Maradini et al. [25] stated that fiber length is another key factor in achieving maximum mechanical properties of composites.
Therefore, the mechanical properties of the resultant fiber-reinforced unsaturated polyester improve

Minor addition is made to have requisite properties suitable for dental prostheses.
In this work investigation was carried out to find out optimum chemistry to have melting temperature of the alloy in the range of 1100-1200 °C without compromising the requisite mechanical and corrosion properties.
Beryllium metal is added to Ni-Cr alloys to improve properties like hardness and reduce fusion temperature [6].
Ni-Cr based dental alloy contain minor additions of other elements for improvement in properties.
Reis, Characterization of two Ni–Cr dental alloys and the influence of casting mode on mechanical properties, J.

Under external loads, the interface of FRP-concrete will emerge inevitable internal force redistribution, and the FRP plate is a kind of resin material and its physical and mechanical properties will change with temperature and time.
In recent years, many domestic and foreign experts and scholars put forward the method which used FRP sheets or plates to strengthen the bridge and research on its mechanical behavior [1-7].
The temperature and creep effect are the main factors impacting on the working mechanism of FRP.
Material Properties of FRP FRP is a kind of compound material, which is made of multi-strand continuous fiber with epoxy resin as base material by gluing, extruding and drawing.
The elastic modulus of FRP plate affected by temperature and time is defined by the equation as below

Moreover, from the point of view of cost, many factors such as the feed bridge, process quality and die scale should be considered.
Drawing is the crucial process and it will affect other processes and die structure.
Forming performance at this area depends on the lubrication, material properties and some other processing conditions.
For the specific drawbead, factors affecting the resistance force mainly are the radius of the round corner, height, width, gap and some other parameters.
Wen: China Mechanical Engineering, Vol. 13-22 (2002), p. 1967-1970