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Considering the site geotechnical investigation report and relative standards, the safety factor of side friction of uplift bored piles in soft rock was defined according to the testing of frictional resistance between concrete short pile and lightly weathered silty mudstone.
The bedrock has no faulted structures, far from the Guangzhou-Conghua Fault and Shougouling Fault and is comparatively complete with undeveloped fissure, well mechanical properties. the bedrock lack variety and occur in the alternating layer of celadon calcareous mudstone and maroon silty mudstone, which have relatively small thickness of monolayer, less than 3 meters and have no different in anti-press intensity of rock.
Local rock has strong different weathering, affected by the lithology and fractures and groundwater.
Site representative borehole diagram as shown in Fig. 1 and rock mechanical performance indexes are shown in Table 1.
Guangdong standard "Design code for building foundation" states that the bearing capacity characteristic value of single friction short pile can be defined by the way of dividing ultimate friction resistance by safety factor that is not less than 3. the problem is that the exact value of safety factor is undefined.

Polypropylene offers high tough, impact, low density and have good binding properties, heat resistance, low moisture absorption, light weight, non toxic.
In the analysis, the percentage distributions of each control factor were used to measure the corresponding effects on the quality characteristics.
The figure 6 (c) shows the effect of spindle speed on drilling of GFR/PP composites and result indicates that spindle speed is not a significant factor affecting the roundness error.
Feed rate and Drill diameter are the highly influential parameters which affect the roundness.
[2] Wakeman MD, Cain TA, Rudd CD, Brooks R, Long AC, “Compression moulding of glass and polypropylene composites for optimised macro- and micro-mechanical properties.

On the basis of thermo-mechanical coupled FEM model which characterized the composites liquid-solid extrusion process, the constant-velocity and non-constant-velocity extrusion process were simulated by 3D thermo-mechanical FEM.
Thermo-mechanical FE Model Set Up FEM Formulation.
The physical model includes the thermo-physical property, the mechanical behavior, the plastic work, friction and frictional heat generation.
The thermo-physical properties of composite were calculated from the thermo-physical property of Al2O3 and LY12 (presented in Table 1) according to the mixing law.
It can be concluded that it is the mode of velocity rather than the average velocity which affect the forming temperature significantly.

Therefore, the frame mechanical properties directly affect the mechanical properties and safety of the towing machine.
And this stress performance had little effect on the overall mechanical properties of frame.
Given the analysis the weight of various parts on the frame have little effect on the stress and deformation of the frame, the main reason having effect on frame is the value of towing load, ZXZ90 towing machine has good mechanical properties doing towing operations.
Adding connecting beam between main beam lateral beam can reduce the stress concentration phenomenon, and this improving measures can further improve the mechanical properties of frame.
After analyzed, we can draw the following conclusions: (1) The tension of wire rope is the determining factor to the mechanical properties of frame; (2) The maximum stress of frame doing towing operation appeared at the area where the main vertical beam connected with the short horizontal beam, and the phenomenon of stress concentration exists to some extent; (3) According to the stress distribution, we can know that maximum stress is much smaller than the yield limit, the deformation of frame is linear elastic deformation, and the mechanical properties and security of frame are very high.

Studies on Mechanical Properties, Fracture morphology and Corrosion behavior of Pulsed MIG welded AZ31B Magnesium Alloy sheets Gurusamy Viswanathan 1,a *, Pitchandi Kasiviswanathan 2,b, Muthukrishnan Nambi 3,c 1Welding Research Cell (WRC), Department of Marine Engineering 2,3 Department of Mechanical Engineering, Sri Venkateswara College of Engineering, Pennalur, Irungattukottai(PO), Sriperumbudur Taulk, Tamil Nadu, India-602117.
Introduction Magnesium and its alloys are prospective candidates to substitute steel and aluminium alloys in many structural and mechanical applications, owing to some of their unique properties like low density, high specific strength and stiffness, high damping capacity, good castability and recyclability.
A crucial factor in MIG welding of magnesium alloy is the energy input into the filler wire.
The macro structure, mechanical properties and corrosion property of AC p-MIGW of AZ31B magnesium alloys plates are investigated.
(3) (3a) (3b) (3c) Fig-3 Macro analysis and Micro hardness test specimen, Fig-3a Microphotography Welded Mg alloy for 140 A, Fig-3b Microphotography Welded Mg alloy for 150 A, Fig-3c Microphotography Welded Mg alloy for 160 A Mechanical Properties of the joints Micro hardness test The micro hardness test was taken at every 1mm on the weld area both in longitudinal and transverse direction.

Study of Stirrer Disc Structure Type on Grinding Performance of a Horizontal Stirred Mill Junkun Jiang1, a *, Weimin Dong1,b, Zhan Su2,c 1Faculty of Mechanical and Electrical Engineering , Kunming University of Science and Technology, Kunming 650500,China 2Jinchuan Group Co.
There are many factors that influence grinding efficiency of horizontal stirred mill, for example: filling rate, the ratio of the balls and material, the size of the medium balls, material properties, and stirrer speed, etc., in addition the influence of the Stirrer disc structure on stirred mill grinding efficiency cannot be ignored [2].
Table 1 The basic parameters of the simulation model Parameter Values Medium ball ‘s diameter /mm 4 Medium ball’s fill rates 60% Agitator rotational speed /rpm 600 Medium poisson's ratio μ 0.29 Medium ball shear modulus /Pa 2e+07 Medium ball material density /kg·m-3 3700 Media - media ball recovery coefficient 0.5 Media - media ball static friction coefficient 0.3 Media - media ball rolling friction coefficient 0.01 Cylinder poisson's ratio μ 0.3 Cylinder shear modulus /Pa 1e+10 Cylinder material density /kg·m-3 7850 Medium ball - cylinder recovery coefficient 0.5 Medium ball - barrel static friction coefficient 0.5 Medium ball - barrel rolling friction coefficient 0.01 The simulation results and discussion Parameters affecting the effects of particle grinding in the cylinder cavity -- The statistical chart of average maximum normal force Fn(max),average particle compressive force Fc,Particle collision frequency Cf,Consumed power P is shown in figure 3~6.
Considering other parameters affecting the effects of particle grinding in the cylinder cavity -- average maximum normal force Fn(max),average particle compressive force Fc,Particle collision frequency Cf,Consumed power P, We can see when the stirred plate structure is T type, the stirred mill grinding efficiency is highest, round’s grinding efficiency is minimum.

Introduction Hetao irrigation area due to the cold climate, so the conveyance channel lining structure is vulnerable to frost heaving damage, not only greatly affect the normal use of the channels, and also spends a lot of human and material resources to carry out repair and reinforcement.
The ignored channels longitudinal impact factors, take the unit length of the composite lining structure analysis and the establishment of a simplified mechanical model.
Channels composite lining structure for frost heave mechanical model of solving The mechanical properties of the composite and the material properties of the material mechanical force big difference [7], in composite lining structure by unidirectional tension tensile force in the form, its interior will produce both tensile and shear deformation -- tension shear coupling; force in the form of composite lining structure by bending role, its internal bending and torsion two variants - the bending and torsion coupling; by a more complex form of the force, it will produce the four basic deformation of the coupling effect.
In accordance with the literature simplified mechanical model for stress analysis[8].
Conclusions 1) According to the trapezoidal channel composite lining the frost heave simplified mechanical model, design and test methods for composite lining structure to overcome the past, empirically and tectonic blindly selected cross-section of the defect. 2) Frost heave force composite Lining Internal Force calculation method provides a theoretical basis for the control of internal forces of the composite lining structure, improve the cracking resistance of composite lining structure. 3) This paper built a mechanical model only takes into account the impact of frost heaving force, while ignoring the normal freezing action, from the view of the material properties of the composite lining structure and engineering practice, in line with the actual engineering.

The main parameters affecting the CM position accuracy is the measurement error of electronic scales.
As for the transmission error of matrix transformation，the main factors of errors are the corresponding direction cosine matrix, namely the corresponding directions angle of the selected six any axis.
(2) Analyze the test error of the motor assembly inertial parameters to find the main factors of errors and give the error calculation formula.
Mechanical Systems and Signal Processing, 2001, 15(1):189-211
[2] R.A.B.Almeida,A.P.V.Urgueira and N.M.M.Maia.Idetification of rigid body properties from viberation measurements.

In recent years, there has been many results for the study of structural properties of granular materials.
Because of the complex, random features, many mechanical properties can not be demonstrated and explained.
The main factors which affect the movement of particles includes: 1.the shear resistance which particles need to overcome(friction force and bite force between particles) [4] [5];2.the exciting force.
Fig. 2 The distribution density of the movement of the particles changes with depth The movement of the particles which is caused by the vibrational energy has been affected by the shear resistance.
It points out: when the friction of the shear resistance is equal to zero, it affects the shallowest depth and the speed reduces fastest; on the contrary, the friction of the shear resistance is greater, it affects the deeper depth and the speed reduces slower.

If concrete is observed at the microscopic level, it can be seen to contain many interfacial transition zones (ITZ), resulting in the weakening of its mechanical properties; as the physical properties of lightweight aggregates (LWA), such as their high absorption, are clearly different from those of normal weight aggregates (NWA), they may lead to variations in the ITZ of lightweight aggregates concrete (LWAC), making its mechanical behavior different from that of normal concrete.This study takes three types of LWA with different rates of absorption as its subjects in order to examine the effects of LWA absorbency on ITZ.
ITZ, Due to the wall effect, concrete bleeding, unidirectional growth of hydration reactants, and other factors, forming properties that differ from those of cement paste.
ITZ, compared with cement paste, is characterized by high porosity and low tensile and adhesive strength, and the thickness, strength, and other factors in ITZ directly affect the properties of concrete; ITZ may therefore be considered the weakest link in the concrete[1-5].
Experimental work This study is primarily focused on investigating the microscopic properties of ITZ in LWAC.
[5] EuroLightCon Document BE96-3942/R2, LWAC Material Properties State-of-the-Art, December. (1998)