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Introduction Cracking significantly affects the behavior of reinforced concrete structures.
Here, the concrete is assumed to be numerically represented with many elements with the same size and the mechanical properties of these elements are assumed to conform to a given Weibull distribution, the finite element method is employed as the basic stress analysis tool to calculate the stress and displacement in elements and the Mohr-Coulomb criterion with tension cut-off is utilized as damage threshold.
The detailed descriptions about the Weibull distribution of material properties and constitutive law of the numerical simulation code have been given more in References [8-10].
Concrete is considered as the heterogeneous material and the constitutive model with residual strength after elastic damages and failed elements are treated with reduced properties.
The other materials mechanical properties for the concrete and reinforcement follow the design material properties used from the reference [11].

Moreover, mechanical reliability also affects hydraulic reliability [12].
Consequently, the properties of reliability (R) can be represented in the following manner [11]: i. 0 ≤ R(t) ≤ 1 ii.
Researchers have studied the factors that affect the condition assessment of water mains using different techniques to obtain a condition for each pipe.
Water network properties (e.g., pipes with their soundings) were extracted directly from the city database.
The weights of other factors, as listed in Table 1, show the differences among critical factors based on land use.

The voids due to the effect of conversion do affect the mechanical properties of concrete.
The factors affect the bond between the deformed bar and concrete are chemical adhesion, friction forces and mechanical anchorage of the ribs against the concrete surface.
These factors may be implicated in three major subject headings: structural characteristics, bar properties, and concrete properties.
In addition, the concrete cylinders were cast for each batch of concrete to determine the fundamental mechanical properties.
The fundamental mechanical properties of concrete are showed in Table 2.

Generally, material with high mechanical properties exhibits low damping capacity and vice versa.
The material properties foreach type of material are shown in Table 2.
The mechanical properties assessed in this experiment are mainly damping capacity, yield strength and ultimate tensile strength (UTS) of the materials.
The high damping capacity is observed in materials exhibiting poor mechanical properties, for instance yield stress or hardness.
From Table 2, it is observed that the mechanical properties of mild steel are higher than aluminum alloy.

These phenomena have occurred due to thermal and moisture gradients and they are affected by different parameters.
The inadequate management of this process can cause severe damage to the product such as cracking, loss of nutritional properties and even loss of the product quality.
When the rice is collected with delay and lower moisture content it affects the amount of whole grains, resulting in the cracking of the grains and quality reduction after drying.
Drying kinetics is affected by several factors that must be analyzed and controlled such as: initial and equilibrium moisture contents of grain and mass flow rate, temperature and relative humidity of the drying air [5].
The general equation of diffusion used by the ANSYS CFX® software for determining of a generic magnitude Ф is given as follows: (1) where Φ is the potential of interest, λ and ҐΦ are transport properties, and t is time.

IN718 alloy possesses excellent mechanical properties at high temperatures, good process ability, therefore, it has been widely used in aero engine turbine disks, compressor disks, and power turbine shafts (i.e., rotating components).
The fatigue properties of the alloy are a key factor that determines the safety and reliability of the engine.
The grain size is smaller, and the low cycle fatigue properties of the alloy are better.
Among the Ni-base superalloys, IN718 is predominantly used in high-temperature applications due to its highly satisfactory price/overall performance ratio, good corrosion resistance and mechanical properties with excellent weldability.
The operational lifetimes of rotating components comprising IN718 alloy are determined mechanical properties, especially the creep and fatigue properties [6~8].

Parametric Analysis Mechanical Properties of Bolted Joints Dazhao Yu1, a, Yueliang Chen2, b, Zhonghu Jia1, Yong Gao1 and Wenlin Liu1 1 Department of Airborne Vehicle, Naval Aeronautical and Astronautical University, Yantai, Shandong, 264001, China 2 Qingdao Branch, Naval Aeronautical and Astronautical University, Qingdao, Shandong, 266041, China a ytyudazhao@yahoo.com.cn, bcly0532@sina.com Keywords: Bolted Joints, Optimal Design, Finite Element Analysis, Contact Stress, Interference Abstract.
Issues in modeling the contact between the joint parts, which affect the accuracy and efficiency of the model, were presented.
Three-dimensional finite element analysis was also used to study the effects of different parameters on the mechanical behaviour of single lap bolted joints.
Due to factors such as bolt bending and tilting, bolt pre-load and secondary bending, stresses and strains in bolted joints vary three-dimensionally[1,2].
Typical material properties for LY12CZ clad aluminum, Young' modulus of 69.6GPa, Poisson's ratio of 0.33 used in the analysis.

The results showed that artificial intelligence prediction was able to more accurately predict the effect of the factors studied on the fracture toughness of PMMA compared to the traditional fracture toughness prediction.
To know how the above factors affect fracture toughness most of the general methods have to be tested on real materials which will cause quite a lot of expenses.
The ASED criterion was predicted based on the materials will be fractured when the average strain energy density around the crack tip over a control volume reaches critical strain energy () which depended on materials and notch properties.
The data preparation was started by reducing the different scale of input factors with normalization technique to range 0 to 1.
The loading rate (R), crack width (C), and crack length ratio (a0/W) was selected as input factors of AI models, and fracture toughness (KI) was selected as output or target of models.

This RVE is made up of N elastic phases as elastic particulates (inclusions), Ypi, and eventually porosities of ϕ volume fraction, Yϕ, embedded in an elastic matrix of mechanical properties Cm.
The particulate group is constituted by (N-1) finite phases of identical elastic inclusion, according to their mechanical behaviors and geometrical properties.
The effective properties of the porous particulate are obtained using the two step homogenization approach [13].
The first step concerns the study of the porous epoxy matrix with respect to a given elastic properties Em=2.2 GPa and νm=0.3.
The average relative error between the iterative prediction and the experiments is around 5% which constitutes an acceptable gap with respect to the nature of the composite which can imply inevitably much unexpected factors, affecting the average properties of the composite, which often are far from the idealized model.

The major effect factors are: thermophysical properties of metallic materials, mechanical properties, parameters and characteristics of spot welding specification and weld thickness, etc.
The main factors of contact resistance are: the state of electrode and workpiece surface, electrode pressure, temperature and hardness of the material to be welded.
Establishment of finite element model The coupling of the thermal, electrical, mechanical and metallurgical process could be directly implemented in the resistance spot welding module of SYSWELD.
With establishment of the model, some unimportant factors were simplified and supposed, assuming that the contact surface was close enough and appropriate contact points could refine contact surface into contact element, taking into account the contact conditions of curvature on electrodes [5, 6].
Compared with the 1.2mm thickness, magnesium alloy plate of thickness 2.0 mm is affected by environmental heat loss largely, It makes the nugget radial radius increased.