Search results

When designing high-rise structures, the deformation under service condition is the dominant control criteria so that among various mechanical properties of concrete, not only compressive strength but modulus of elasticity is also critical.
It was found that water/binder ratio and properties of aggregate are two main factors determining the elastic modulus of concrete [4].
Then, the properties of the high modulus concrete developed are characterized.
Effect of aggregate properties on the strength and stiffness of lightweight concrete [J].
The effect of silica fume and high-volume Class C fly ash on mechanical properties, chloride penetration and freeze–thaw resistance of self-compacting concrete [J].

And the structural design of frames is not only concerned with the functional reliability of vehicles, but also a key influential factor to the vehicle vibration characteristics.
According to properties of engine excitation, the vertical and lateral vibration level differences between two ends of cab’s four isolators was measured and shown in Fig.4.
It could be speculated that stiffness insufficiency of frame’s front part and cab mounting brackets were kind of important influential factors to be paid more attention to.
It could be concluded from the case study in this paper that frame structure is a significant influential factor of vehicle vibration level.
Journal of mechanical engineering(2011).

To get single-layer of graphene, exfoliating fully intercalated graphite oxide into single- layer graphene oxide is one of the important factors.
Graphene have numerous potential applications [3-5], because of its unusual electron transport properties and other distinctive characteristics.
Hence, increasing the layer distance of graphite oxide is a elementary factor to prepare single-layer graphene.
(b) graphite oxide which were synthesized with ultrasound power of 180 W b2 and mechanical agitation b4 in the Low-temperature Reaction and its reduced products b1, b3 reduced from b2 and b4, respectively.
XRD patterns of graphite oxide with ultrasound power of 180 W (b2) and mechanical agitation (b4) in the Low-temperature Reaction and its corresponding reduced products b1, b3 was showed in Fig. 1 (b).

Introduction During the last decade, the study on inherently conductive polymers such as polyaniline (PANi), polypyrrole (PPy) and polythiophene (PTh) have been increased significantly due to their advantageous morphological and structural properties.
Among them, PPy has captured many attentions due to its unique properties such as simple synthesis route, high conductivity, good environmental stability and exhibits good mechanical properties [1,2].
Molecular size and charge of dopant are the main factors that influence the conductivity [3].
Various factors such as the presence of surfactant, reaction temperature and reaction time affected the conductivity and yield of PPy.

Introduction With regards to their biological and physicochemical properties, PEEK based biomaterials have been successfully used in osteoarticular and maxillofacial surgery [1,2], mainly as endosseous implants.
Clinical success has been achieved not only by the mechanical properties and biocompatibility [3,4] but also by others characteristics such as surface properties.
Surface Roughness is one of the key factors for the osseous integration of orthopaedic and dental titanium implants and can be easy applied to PEEK for osteoconduction improvement.
This sandblasting procedure has been proven to cause a contamination of implant surface which can have unfavourable affects on its bone integration.
The present in vivo study confirms the bioactive property of RBBM blasting to improve the performance of the PEEK implant.

The dynamic parameters directly affect the correctness of engineering design and numerical simulation.
Now domestic scholars generally test the dynamic properties of permafrost through triaxial tests.
The physical properties of silty clay are presented in Table 1.
The physical properties of the soil samples are shown in Table 1 , and particle size distribution in Table 3.
Conclusion The dynamic properties of the frozen soil had become an emergent subject which needs further research.

As is known to all, there are many interference factors in the tunnel advanced detection of TSP, such as holes of poor quality, charge of unseal, the poor coupling relationship of the detection probe, the noise in the hole and so on.
This paper introduces the influence factors and parameter selection of TSP advanced prediction through practices research of TSP advanced prediction in Sheng Ren Moutain tunnel.
If dosage is too big, it will lower detection frequency and detecting resolution, and it will produce huge clutter, affecting the calculating velocity of follow-up to pick up early wave.
When collecting the data by means of TSP advanced prediction, the collection data contains many interference waves and the main frequency is not apparent due to various artificial interference or other interference factors.
Those influencing factor is hard to avoid.

(3) Analyses of the codes mentioned above reveal two main aspects of factors affecting flexural stiffness, which have also been concluded by previous test results, i.e. exterior load factor, Mcr /Mk, where Mcr and Mk represent cracking moment and service moment, respectively, and inner factors including initial elastic flexural stiffness, B0, and longitudinal reinforcement content, ρ.
Unlike them, the suggested formula here is easier to use for its simpler unified form and clearer concepts reflecting main factors' influence on flexural stiffness.
[13] Li Meiyun: The study of the mechanical property of HRB400 reinforced concrete members.
[14] Zhangting: The study of the mechanical property of HRB500 reinforced concrete members.
[19] Feng Hui: The study about the mechanical property of post-tensioned prestressed flexural members with HRB500 steel bars (M.Sc., Zhengzhou University, Zhengzhou, China 2007) (In Chinese)

Introduction With the continuous improvement of material strength on design, the demand of ductile iron is on the increase because the nodular cast iron has excellent mechanical property, and has been widely used in the machinery industry in recent years.
Phosphorus is also easy to segregation, sulfur is certain deplete more nodulizer, seriously affect the nodulizing of molten iron.
Reasonable spheroidization process can ensure the premise of mechanical properties of ductile iron and reduce the nodulizer dosage.
Selected Wuxi nodulizer H-I according to the performance requirements of cylinder casting and the actual production conditions, dosage is 1.2 to 1.4%, thrust forth Into underside of the ladle, at the same time in order to improve the mechanical properties of ductile iron and metallographic structure, using two breeds, adding 0.15% ferrosilicon powder particle size is 20 to 150 for the purpose of molten iron instantaneous birth in the casting process.
(5) Other fields, there will be many influencing factors when produce thick-walled ductile iron parts by the way of greensand manufacture, if you omit, will lead to casting scrap, therefore, the production plant should establish a strict process specifications and quality assurance measures.

Thermo-mechanical experiments were carried out to study the effect of deformation speed and temperature on the behaviour of a non-quenched and tempered steel during hot forging.
Theoretical guidance for the process of hot forging, mold optimization and the control of microstructure properties should be effectively provided to promote the accuracy of the finite element method to simulate the forging process of non-quenched and tempered steel, On account of the hot forming behaviour was affected by many factors, the proper high temperature flow stress-strain model which can reflect micro-deformation mechanism is the foundation of accurate simulation [2].
ƒIn a variety of stress level, the relationship between flow stress and strain rate can be represented as Eq(7): (7) A is the structure factor, in units of s-1; α is stress level parameter, in units of MPa-1; and α = β / n.
According to the linear relationship the average value of hot deformation activation energy Q was obtained as 534.55KJ/mol, as well as the structure factor A was calculated as1.2903 × 1019s-1.
Therfore, proper process should be selected in compliance with material properties and to achieve the requirements of the parts