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Probabilistic Analysis of Three-Dimensional Beams with Uncertain Damage Cristina Gentilini1,a and Lucio Nobile1,b 1 Distart Department, University of Bologna, Viale Risorgimento 2, 40136, Bologna, Italy a cristina.gentilini@unibo.it, b lucio.nobile@unibo.it Keywords: three-dimensional beams, cracked beams, stress intensity factor.
A computationally efficient and accurate method has been presented in [1] to study truss structures with uncertain geometrical and mechanical properties and, such approach has been extended in order to analyze linear elastic truss and frame structures with uncertain crack depth and crack location in [2].
Let assume that the structural element is affected by uncertainties, which influence the compliance matrix: ( )aa a=C C β (2) where βa is a vector of uncertain parameters modelled as random variables.
All these compliances are function of the dimensionless crack depth ξ and related to the Stress Intensity Factors (SIFs).
For the considered B×H rectangular cross-section with an edge crack, Fig. 2, the stress intensity factors can be put in the form: ( ) ( ) ( ) ( ) ( ) ( ) I I II 2 III III 3/ 2 3/ 2 6 , , 1 2 , z z y y z z x x y z N N M M S S x z S S T T S M N K H F K H F K H F BH BH B H T S K F K F BH BH πξ ξ πξ ξ πξ ξ ξ ξ ξ = = = − = = (11) where the correction functions FN, FMz and FSy are taken from [5] while FTx and FSz are given by [3] and [6], respectively.

Effects of Electrode Degradation on Properties of Small-Scale Resistance Spot Welded Joints of E110 Alloy Alexey S.
As a result, chemical composition and thermo-physical properties of the electrode tips have been changed.
Dynamic resistance between electrodes was statistically processed in an attempt to predict and control properties of the nuggets.
Parker, Review of resistance spot welding of steel sheets: Part 2 – Factors influencing electrode life, International Materials Reviews 49(2) (2004) 77-108.
Eagar, Measurement of dynamic electrical and mechanical properties of resistance spot welds, Welding Journal 66(12) (1987) 378-385

Introduction Under environmental and the load effects, the factors affecting the service life of infrastructure are complex.
In the reinforced concrete structure, the crack width is controlled by reinforcing steel, corrosive substances will penetrate through the cracks causing the steel to corrode, swelling stress will occur, leading to spalling of concrete cover, seriously affecting the structural durability and safety.
The properties of PVA fibers are listed in Table 1, and the mix proportions of ECC in Table 2.
Table 1 The properties of PVA fibers No.
In the period of strain hardening, the strength of JE6 declined slower than that of JE5 and JE4 indicating that the crack resistance and toughening effects of JE6 is higher than that of JE5 and JE4. 3.2 Uniaxial tensile properties Table 3 Uniaxial tensile mechanical properties for ECC No.

This paper aims to develop a three dimensional(3D) finite element model for a section of pipeline under axial membrane stresses, which contains two high-aspect-ratio semi-elliptical internal surface cracks, and further uses it to investigate the effect of the separation distance of these two cracks on their fracture mechanics properties( e.g. the stress intensity factor and the -stress ).
Formulation of stress intensity factors and -stress The stress intensity factor and the -stress over the fronts of the relevant surface cracks are two key fracture mechanics parameters used in this paper.
In linear elastic fracture mechanics, the stress intensity factor is often assumed to be a unique parameter that controls the fracture process.
From these figures, of the point , rather than the other points and , is more affected over the separation distance of the two cracks which is almost one time of the half-crack length of the cracks, while -stresses of all the three points are only sensitive within the separation distance of one quarter of the crack length.
American Petroleum Institute, The American Society of Mechanical Engineers.

The structure and properties of copolyimides were characterized by FT-IR, UV-vis and solubility testing, and the effect of monomers on the properties of polyimides was also investigated.
They are extensively used not only for their excellent thermal stability but also for their good mechanical properties, low dielectric constant, low coefficient of thermal expansion and high radiation resistance [1].
The paper reports a study of the synthesis and properties of a soluble and transparent copolyimide.
The effects of mole ratio on the solubility and optical properties of PI copolymers were studied.
Therefore, the results demonstrate that the intermolecular interaction of polymer chain is very important factor that affects the solubility of polyimides.

The production of cold-rolled sheets is correlated with the rolling of metals with various mechanical properties and formability, a changing reducing passes, variable rolling speeds, thermal metal heating, wear of working rolls, tension between stands and other factors.
These factors significantly affect to the conditions for the formation of barrel profile of working rolls, which should provide the necessary level of residual stresses and strains in sheet metal products, and the required flatness of sheets and strips.
During cold rolling the form of the roll gap is not constant [5], and depends on the properties of the metal, the type of mill, the rolling pressure, the length of the rolls, the location of the back-up rolls and other factors [6] that affect to the flatness of the rolled products and should be taken into account in AASPS of the strip.
At the same time, consideration of the properties of materials, hardening during cold deformation [13, 14], is not given enough attention.
The authors took into account many factors here (the temperature field of the rolls, the temperature field of the strip, the rolling speed (bite), the tension of the strip, and others) that affect to the size of the strip-crown.

Introduction Machine tool supporting pieces have greater affect on its dynamic characteristics.
By joining the stuffing, it not only can reduce resin content, reduce cost, but also can improve the physical and mechanical properties of the polymer concrete.
Accordingly, we can estimate factor by the resonant shape.
This is a common method of the factor determination by test.
When factor is very small (such as factor < 0.05), .

Material thickness and mechanical properties testing may be required at many locations or may be sufficient on a random sampling basis.
The site specific physical and chemical properties of seawater may also play an important role, and are likely to be of significance to the shipunloader, and also to the underlying jetty structure.
Strength and fatigue assessments, based on the corrosion affected geometry, and in-situ material properties, were to be carried out.
The ranking method chosen is a simple qualitative comparison using factors of 1 to 5 for each element.
The ranking of consequence uses the worst of each of these factors to derive the ranking.

C0 / (C0 + C) showed that variation features of sample, the greater the value was the more variation was caused by random factors ,the table shows only clay on 0 ~ 20 cm level C0 / (C0 + C) value was small, its less affected by random factors, which caused by structural factors account for over 70% of the total variance of mutation, showed a strong spatial correlation; C0 / (C0 + C) value to other size of soil was greater than 0.52, less than 0.8, it were more affected by random factors (reclamation process, order, covering method, etc.), less affected by structural factors, and had a medium spatial correlation [27].
C0 / (C0 + C) showed that 0 ~ 20 cm layers of clay C0 / (C0 + C) value was small, its less affected by random factors which was caused by structural factors account for over 80% of the total variance of mutation, be a strong spatial correlation; Other size of soil C0 / (C0 + C) value was greater than 0.52, less than 0.8, it more affected by random factors (reclamation process, order, covering method, soil source, etc.), less affected by structural factors and had a moderate spatial correlation
Spatial variability of soil properties in the field based on GPS and GIS[J].
Spatial variability of soil properties and weed populations in the MississippiDelta [J].
Neural network ensemble residual Kriging application for spatial variability of soil properties[J].

The temperature dependent material properties for all layers reference to literature [8, 9].
The creep properties strongly depend on the temperature.
TGO thickening significantly influence S22 stress, and affect the TBCs failure directly.
W.Liu, Research progress on the experimental measurement methods of mechanical properties of thermal barrier coatings, Chin.
Dubois, Simulation of the effect of material properties and interface roughness on the stress distribution in thermal barrier coatings using finite element method, Mater.