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Moreover, aluminium metal matrix composites are characterized by excellent properties as combination of properties which comes from the matrix and from the reinforcement.
An optimum set of mechanical properties tends to be obtained when fine and thermally stable ceramic particulates are dispersed in a metal matrix.
a b c 590ºC 45 min 590ºC 45 min 570ºC 30 min 600ºC 30 min Regarding composites final properties, it can be pointed out how the addition of TiCN has a strong influence on the mechanical properties.
The TiCN agglomerations are located between Al particles and pores, hence the decreased mechanical properties since these zones could act as strain concentration points.
- Aluminium metal composites reinforced by TiCN particles presents higher sintered density values, although the mechanical properties are reduced due to the ceramic particles location.

Further, an increase of yield strength has to be achieved in order to improve the crash properties, which can be reached by an artificial hardening process during paint drying [3].
(6) Solving equation (5) and (6) by the force F and equating them to each other, the deflection becomes dependent of the total maximum bending strain εmax as well as the geometric properties l and s0.
A linear interpolation of the product of the previously determined time and stress factors leads to A=1,9·10-7 (N/mm²)-ns-m and a standard error of about SE=1,2·10-9 (N/mm²)-ns-m (=1 %) As visualized in Fig. 7, the creep behavior can be sufficiently described by the power law within this stress range.
Regensburger, Numerical Prediction of Thermal Panel Distortion incorporating Thermal Material Properties of 6016 Aluminium Alloy, European Aluminium Congress, Düsseldorf (2011) [5] S.
Courtney, Mechanical Behavior of Materials, McGraw Hill, Boston, 2000 [9] J.E.

Deterioration due to decay or insect attack, member failure, mechanical damage or alterations and other conditions can adversely affect the performance of structural timber even though it may appear to meet the requirements for a particular grade.
Material must be removed from the structure so that mechanical tests can be conducted to determine a material property of interest.
Nondestructive testing has been used for decades to estimate material properties.
Over time, grading rules were modified as more technical data became available on material properties, and the effects of knots, slope of grain, and other defects on material properties were better understood.
Evans, Evolution of Standardized Procedures for Adjusting Lumber Properties for Change in Moisture Content.

Moreover, ZnO has excellent piezoelectric properties, which make it widely used as acoustic devices [7].
The influence of annealing atmosphere on the structural and optical properties of ALD-ZnO thin films was evaluated.
And annealing process will also significantly affect the surface morphology.
Lai, Influence of annealing temperature on the structural, optical and mechanical properties of ALD-derived ZnO thin films, Appl.
Mathur, Thickness dependence of optoelectronic properties in ALD grown ZnO thin films, Appl.

The loess formation age is relatively late whose physical and mechanical properties are relatively poor, and the conditions of topography, geology, hydrological geology and climate are complex, so many distresses in the construction process of loess tunnel are produced.
The observation, investigation and statistics of creaks in tunnel pavement and tunnel body are immediately progressed together with the detection and observation of tunnel distress, and the protoliths at the back of tunnel sidewall and the bottom of pavement have high water content partly presenting argillization with plastic state; the unidirectional compressive strength is much less than the original design value, the thickness of partial lining is inconsistent with the original design thickness, the stress state of tunnel lining structure is affected.
The settlement of sidewall foundation on one side of tunnel lining still develops slowly owing to the intenerating of mudstone leading to the cracking of upper concrete in pavement, and long longitudinal crack is also produced in the additional concrete pavement; the water constantly seeps in the tunnel arch creak, and much groundwater flows from creak to tunnel in rainy season and the water of winter pavement turns into ice affecting the driving safety within tunnel.
The shear stress inside lining structure reduces after treatment of this scheme, the whole tunnel lining is in pressure state fully performing the compressive property of concrete; the lining structure turns into an enclosed ensemble by setting inverted arch and the stress of lining structure improves greatly.
a) Before treatmentb)After treatment Fig.4 damage rating before and after treatment of the tunnel Conclusions The overall detection towards tunnel distress is progressed by GPR, non-metal acoustic scanner and detector of laser delimitation; the causes of the distress are analyzed, and the treatment thread of backfilling grouting cavern rearward lining, reinforcing the lining by increasing thickness and processing the waterproof and drainage towards tunnel is brought forward; the optimal treatment scheme of tunnel distress is given in accordance with the analysis of finite element, construction factors and project cost.

This property is often suitably used, especially in the concreting of massive structures, e.g. dams.
In this way, the test sample’s physical and mechanical properties, or any defects, can be determined.
Therefore, having a positive effect on the resulting mechanical parameters of the composite.
It needs many further experiments to determine the exact impact of using this type of by-product on the properties of the concrete composite, especially on its microstructure and durability.
Evaluation of Fresh Properties and Rheology of Mortar Using Carbon-Free Fly Ash and Normal Fly Ash.

Because these properties degradation models used constant factors for elastic properties reduction due to damage growth, the models weren’t be able to predict the bearing final failure.
The difficulties arising from composite material usage on structural failure analysis, are that these materials have anisotropic mechanical properties, brittle and low inter-laminar strength [15].
Mechanical properties of the materials.
These special solid elements has bending properties like shells and one integrating point per element.
[17] *** MMPDS-05, Metallic Materials Properties development and Standardization, FAA, 2010 [18] *** ASTM D 3039, Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials, ASTM Int. 2007

The bulging process for multi-branch tubes is to drive the tubular blank to expand outward along the radial direction under pressure, depending on the plastic properties of the tube materials.
The tubular blank parameters are optimized, whilst process factors such as friction, balance force were analyzed.
Fig. 1 Compound forming of Fig. 2 Tube blank Fig. 3 Finite Fig. 4 Thickness T-branch tube dimensions element model reduction during forming Determination of tubular blank parameters Tubular blank parameters analysis and experimental design The main blank parameters affecting the forming process are initial tube length l0, initial wall thickness t and die entry radius R
Values of die entry radius directly affect the choice of t and l0.
For above reasons, the factor of l0 is laid out with four levels of 96,104,112 and 120.

However, NR possesses a poor weather resistance and poor wet grip properties.
Hence, chemical modifications of NR are essential to overcome these undesirable properties.
They evaluated the influence of different factors such as water absorbency, polymer coatingpercentage, pH and temperature on the release behavior.
It is found that the variation of temperature has a significant impact on the urea release more than other factors.
Abdullah, Effect of rice husk surface modification by LENR the on mechanical properties of NR/HDPE reinforced rice husk composite, Sains Malaysiana, 40 (2011) 749-756

Other factors, like coal production processes, daily coal output and advance speed also have close relationships with gas emission. 0 Introduction Fully mechanized caving mining is an important technology for mining thick coal seam [1, 2].
But gas over limit on mining face upper corner has become the biggest restricting factors for safe mining in the Daiyang coal mine because the thickness of coal seam is large in the mine and lots of coals left behind in goaf.
Tab. 1 Roof and floor lithology of 3401 working face Classification Rock Average thickness(m) Rock characteristics Main roof Grey middle sandstone 8.8 Silicon-calcareous cementation, contain locally large amounts of muscovite, sometimes contains carbonaceous belt Immediate roof Grey-black mudstone 4.3 Contain locally grit siltstone, contains thin coal seam in upper part False roof Grey-black mudstone 0~0.5 / Direct floor Grey-black mudstone and fine siltstone 9.0 / Main floor Grey quartz sandstone 2.25 Calcareous cementation, separation medium, angularity particles Tab. 2 Gas basic parameters of coal seam Coal seam Gas pressure (MPa) Gas content(m3/t) damping factor of gas flow rate per hole α(d-1) Permeability coefficient λ (m2/MPa2•d) 3# 0.05~0.11 4.23~5.10 0.2430~0.2919 3.436~6.811 The E type three-roadway layout is in the mining face.
So caving coal one-time and largely had a greatest influence to gas emission in fully mechanized caving working face. 3.2 Relationship among gas emission, daily output and advance speed Related research at home and abroad determining that gas emission is mainly affected by mining production, gas emission is generally considered not proportional to the production of working face [5].
The relative gas emission is 2.34 to 6.91m3/t and keeping with a basically stable state. 4 Conclusions (1) The mechanical properties such as gas pressure, porosity and permeability has a greater change because of the abutment pressure in front of working face, which make the gas emission is unbalanced