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The symmetricity in the crack initiation at the counter side of stress concentration is severely affected by the loading pattern [6].
The material property of the laminate corresponds to a woven GFRP impregnated with epoxy resin, shown in Table 1.
Mechanical properties of GFRP laminate.
The subsequent significant failure observed was circular notches, and the square notches were comparatively less affected.
[7] ASTM D3039/D3039M-17 (2017) Standard test method for tensile properties of polymer matrix composite materials.

For characterization of the mechanical properties of monolithic neat and filled polymers, the mixture prepared as described above (without blowing agents) was poured in plastic ampoules of ca. 14 mm diameter and 80 mm length.
Based on dimensional considerations, relations for mechanical properties of foams, expressed in terms of cell wall material characteristics and foam density, have been derived in [5].
Substantial improvement in foam properties was observed.
Tong, Surface-modifiers of clay on mechanical properties of rigid polyurethane foams/organoclay nanocomposites, J.
Skala: Mechanical Properties and Energy Absorption Characteristics of a Polyurethane Foam (Sandia National Laboratory Report SAND97-8490, 1997).

In this context, previous studies [18]–[20] investigated the effects of other factors, such as w/c ratio, aggregate size, and volume of coarse aggregate on the behavior of a conventional concrete mixture.
The findings showed that increasing the aggregate size to 20 mm, decreased the fresh properties and enhanced the SCC’s mechanical properties.
It was found that the fresh properties were increased, and the mechanical properties decreased with the ratio of w/p in the SCC.
Furthermore, the performance of SCC was investigated in order of fresh concrete properties and mechanical properties.
Xie, “Mechanical and durability properties of recycled aggregate concrete: effect of recycled aggregate properties and content,” J.

It is expected to find a value large enough to have a small penetration, without affecting significantly the behaviour of the analysis.
Table 3: Comparison between different penetration limit factors - Contact between two cylinders.
The material properties are E = 210 GPa and ν = 0.3.
Table 6 shows the results for different stiffness factors in terms of the number of iterations and computational time.
Moreover, the stiffness matrix can become ill-conditioned, affecting the convergence and also leading to higher amounts of computational time.

But we encounter many experiments with possibilities of input factors more than one.
Teimouri, “Friction stir welding of aluminum 6061-T6 in presence of watercooling: Analyzing mechanical properties and residual stress distribution,” Int.
Vasanthakumar, “Microstructural and Mechanical Properties of Dissimilar Aluminium Alloys by Friction Stir Welding”.
Vasanthakumar, “Mechanical and tribological properties of Al6063 hybrid composites reinforced with SiC/ZrO2 by stir casting and thixoforming process,” Mater.
Vasanthakumar, “Mechanical properties of Al-Cu alloy metal matrix composite reinforced with B4C, Graphite and Wear Rate Modeling by Taguchi Method,” Mater.

Analysis and Improvement Excellent mechanical properties of saw baldes are obtained after heat treatment: good dynamics , even hardness and uniform stress,these characters can ensure the saw blade is not distortion easily in sawing.
But if we want get saw blades of high properties,we mast master temperature , time and quenching hardness in the process of heat treatment.
There are three factors in this test: tempering temperature(A), tempering time (B), quenching hardness (C) , each factor can take three levels, the level of test factors is shown in table 3.
Table 3 The level of test factors Tempering temperature (A) Tempering time (B) Quenching hardness (C) Other factors 1 6h 60HRC 1 2 8h 62HRC 2 3 10h 63HRC 3 We choose L9(34) orthogonal table to begin the test , and record results of each test, results is shown in table 4.
We can also list the primary and secondary factors according to range analyse,temperature is prioritized, tempering time and quenching hardness are following .

This method is used to study the fracture characteristics of concrete and measure the stress intensity factor of I type crack tip.
Material properties of concrete are greatly improved and load bearing conditions are more complex [1].
For example, the method has the requirement of surface features and illumination because of correlation calculation of intensity distribution; Correlation calculation is implemented through transition of subregion and affected by rigid body rotation.
In this paper, the method is introduced to study fracture characteristics of concrete and used to measure I type crack tip stress intensity factor of concrete.
Displacements of crack tip can be obtained by white light digital image analysis in frequency domain and stress intensity factor IK can be calculated.

However due to the randomness of all these properties, the fatigue crack growth (FCG) is a process that is naturally considered to be random [5] and requires appropriate inspection plan in order to prevent the risk of failure and improve maintenance strategies.
The fracture can be described by the use of the stress intensity factors in various modes.
Three factors a0, C and ac (or ad), presented in table 1 are considered, each at three levels (eq min, max and middle values ) where 27 run simulations has been conducted using general full factorial DoE.
Crack size (m) Fig.4: a=f(N) deterministic case Fig.5: a=f(N) random case Referring to the figures above, for a target critical crack length a very significant scattering of the life cycles is observed, hence the necessity to take into account the uncertain parameters affecting the propagation.
[33] Parks MD: A stiffness derivative finite element technique of crack tip stress intensity factors.

Large number of welds results in complex residual stress and deformation, and the residual stress and deformation has adverse effects on structural fracture property, fatigue strength, accuracy and stability of shape and size.
Weld1 Weld2 Weld3 Weld4 Fig. 1 Finite element model Physical parameters of the material During the welding process, the thermal and mechanical properties of the material have decisive influence on the distribution of temperature field and the formation of residual stress, so it is important to establish the material physical property database first.
All the other physical parameters for thermal and mechanical property were obtained from experiments, which tested all the necessary the parameters of the SMA490BW, based on the parameters, the database for SMA490BW was established.
From Fig. 5 and Fig. 6, it can be seen that if all the factors remain unchanged and change welding sequences only there is no obvious change in the peak value of residual stress in the welding direction.
Besides unlike the experimental results the peak value of residual stress appear in the heat-affected zone instead of the weld zone.

The paper will discuss the analytical modelling equations and factors currently used for designing interference fits to resist the load components, followed by Finite Element Analysis (FEA) in order to investigate slip criteria for failure of interference fits.
The most important factors in the theoretical calculations of holding force and holding torque are the interference, which is directly related to the interface pressure, and the coefficient of friction.
The discrepancy in the results may suggest a problem with the values of these factors used to calculate the failure loads theoretically.
[5] in fact sheet: “ESDU 68002 - Shafts with Interference Fit Collars - Part 1 Some Factors Affecting the Design of an Assembly
Haugen, in: Probabilistic Mechanical Design, Wiley, New York, (1980).