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Table 1 Physical properties of coarse aggregates Type of coarse aggregates Apparent density [（kg·m-3）] Crushing value (by mass) [%] Water absorption at 30 min(by mass )[%] Soundness index[%] Natural 2673 14.3 1.2 — Recycled 2544 17.3 3.7 8.1 Table 2 Physical properties of fine aggregates Type of fine aggregates Apparent density/[kg·m-3] Fineness module Water demand ratio Absorption at 30 min(by mass)[%] Compressive strength ratio Soundness index[%] Natural 2616 3.02 — 0.20 — — Recycled 2424 3.09 1.33 9.4 0.79 7.2 Test Methods The absolute density of volume method was used to design mix proportions according to the recycled aggregate pre-absorbent method proposed by Zhang Yamei[10].
In order to improve mechanical properties of concrete, air entraining agent and polypropylene fiber with 0.1% were added.
Analysis of factors affecting the frost resistance of recycled aggregate concrete From the analysis of aggregate gradation of recycled coarse aggregate concrete, it could be known that aggregate gradation was an important factor affecting the frost resistance of concrete.
It also indicated that the addition of RFA had an obvious negative effect on the frost resistance than RCA, and aggregate gradation was an important factor affecting the frost resistance of concrete.

Test Study on the Resisting Shear Strengthening Effect with External Pre-Stressed Wire Rope Tianlai Yua, Qiang Mab and Leilei Tianc School of Civil Engineering, Northeast Forestry University, Harbin, 150040, China atianlaiyu@126.com, bmaqiang745@163.com, ctianleileihenan@126.com Keywords: Wire Rope; The Shear Strengthening; Influencing Factors; Reinforced Concrete Beam Abstract.
The resisting shear strengthening technology of existing reinforced concrete bridges as an important research topic in the field of old bridges, play an important significance to improve the mechanical properties of old bridges and reduce security incidents.
Introduction The shear capacity of some of the old bridges is not enough because of heavy vehicles and natural factors.
Because the effect was affected by many factors, such as the original beam reinforcement ratio, the original beam stirrup ratio, concrete strength, the spacing of external wire rope and the level of staying load when reinforcing and other factors, so these factors were analyzed in this paper.
The ultimate loads measured actually are listed in Table 5.With other factors remaining the same and only a factor being changed separately.

However, such extensive manual polishing will provide some drawback because of many human factors such as pressure and technique of polishing individual person uses.
JIS FC300 gray cast iron has good mechanical properties with good machinability [3].
The combination of graphite strengthening microstructure and excellent mechanical properties have led to FC300 being used in a wide range of industrial applications such as automotive parts, internal engines, piping systems and construction parts [5].
Among the factors that can be influence surface quality of the product is cutting parameters such as cutting speed, feed rate, depth of cut, tool geometry, tool wear, and workpiece properties [6].
The area affected recorded around up to 6um beneath the machined surface.

Solid tetrahedral element is used to mesh with material properties of QT450-10 [2].
In operating, the dynamic load sources are not only from road roughness but also from the flowing of hydraulic oil in system [9], therefore MSC.Adams/Hydraulic module is used to describe environment of hydraulic system with parameters of hydraulic cylinder, oil operational pressure and properties.
The fatigue properties of material QT450-10 is used to create S-N curve of material.
Therefore, getting over blocks will affect fatigue life greatly.
Fang and Editorial Member: Mechanical Engineering Material Features Data Manual (Mechanical Industrial Publications, China 1994), p.753 (in Chinese)

Recently, polysiloxane has been utilized as a LED encapsulant due to its attractive combination of good chemical resistance, optical and mechanical properties [3].
The aromatic structure of carbazole will significantly affect an increase in optical properties.
Optical and thermal properties.
The two factors that effect the value of dn/dT are cooficient of thermal expansion and electronic polarization coefficient.
Part I: Synthesis and thermal properties, Polym Degrad Stab, (2011).

It has high technological, physical and mechanical properties and meets modern requirements of Russian regulatory documentation; 3.
The value of molecular weight and flexibility of the macromolecules significantly affect behavior of polymers at mechanical failure 5.
The mechanical properties of polymeric adhesives have a large the effect of the degree of branching of chain molecules References [1] M.A.
Kuleznёv, Structure and mechanical properties of polymers: studies, manual for schools, Higher School, 2002, p. 320
Claver, M.C., Baer, Fracture and mechanical properties of polymers, 22(2005), J.

The material material performance characteristics of black clay mineral Mineral material is the natural mineral and rock which can be directly utilized its physical properties and chemical properties, or processed natural mineral and rock which can be formed new material.
The porosity is from 29.03% to 51.46%, bibulous rate is from 20.02% to 39.28%, volume density is from 1.15 g/cm3 to 1.89 g/cm3, compressive strength is from 2.07 MPa to 9.86 MPa.They are discussing the influence factors for the performance of the products the which include hole agent, sintering temperature, adhesive and dosage, molding pressure, holding time of factors affecting.
Burning expansivity : the chemical composition of raw materials is the main factor to affect the expansion of roasting ceramisite.
Physical properties : for particles of illite shales, the finer the better, and for the amount of sand, the less the better.
Compared with the performance of marble, granite and other natural stone, the properties of glass ceramics samples prepared by illite shales - nickel-molybdenum-vanadium slag is superior.

By the method of numerical simulation the variation law of stress-strain with time and space around borehole of impermeable rock medium, variety law of rock physical properties parameters is studied.
To the boundary of reservoir, the flow pressure decreases very quickly. 1 Introduction There are a large number of pore or fracture.These defect not only change widely the mechanical property of rock mass,but also affect seriously the permeability of rock mass.There is fluid in the pore of rock mass.Seepage field of rock mass is affected widely by the environment,and the change of seepage field affects stress field in turn.So,the coupling between seepage field and stress field forms.As a result,in the processs of oil and gas development,the intercoupling action between seepage field and stress field should be considered.
Tong dengke(2005) has summarized and discussed the research progress of fluid-soild coupled flow of porous media,put forward the further research direction and discussed emphasizly oil and gas fluid-soild coupled multiphase flow and application research,providing reference for other seepage engineer[2].Song shaoyun(2007) has made theoretical research for the general many fields coupling problems and put forward the collaborative solution of analysing these problems.He also has made further research for the key technology of this methord, put forward collaborative solution methord of many fields coupling problems and studied key technology[3].ZhaoYizhong(2009)comprehensive considered the role of fluid-solid coupling, the effect of dynamic-made sewing, variable fracture conductivity and other factors, established a new model of de-sand fracturing unconsolidated sandstone reservoir productivity and carried out the optimization of de-sand fracturing capacity under the influence of the factors
Table1 Coupling computation model parameter (holediamete) crustal stress (Mpa) Pore pressure (Mpa) Mud pressure (Mpa) Material properties (Drucker—Prager type) external boundary: Inner boundaty: permeate: inpermeate: Modulus of elastic: Poisson’s ratio: friction angle: cohesive strength: tensile strength: Because the variation of non-linear stratum medium depends on load path,in oader to dispose reasonabling the relationship among three loads - crustal stress,borehole pressure and pore pressure, the pressure change of far field is disposed as two interconnection time interval.
Fluid-solid coupling simulation of deliverability of screening out fracturing under influence of multiple factors[J].Journal of Liaoning Technical University(Natural Science), 2009, 28(Suppl): 54-57.

Many factors [2,3], such as cement, mineral admixture, W/C ratio, construction or curing conditions, etc., will affect the bleeding of concrete.
The major factors of influencing the concrete bleeding are W/C ratio, the amount of cementitious materials and the sand ratio.
The W/C ratios can greatly affect the concrete chalking.
The moulding methods were hand mixing and mechanical vibration, respectively.
However, the specimen K3 displays seriously chalking owing to the mechanical vibration during the moulding process, indicating the mechanical vibration will accelerate the concrete chalking.

In paper, the design of micro gear hob and the micro hobbing technology is the key factor to the manufacture of micro gear and is presented detailed.
Introduction With the trend of product miniaturization, Micro-Electro-Mechanical Systems(MEMS) is applied in many fields and studied by many people.
In contrast, fine grain carbide is better than high speed steel in the mechanical properties.
But the length of the cutting should not be so long that will increase error of the accumulated pitch and hob helix, resulting in manufacturing difficulties, and reduce the precision level of gear hobs, thus affecting the accuracy of the micro gear.
So the normal tooth profile can be determined by the gear and the parameter of the axial direction is affected by the helix angle.