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It is found that the shapes of the coarse aggregates do affect the tensile strength and failure pattern.
However, as is well known, the mechanical behavior of concrete is rather complicated, especially when it is under high strain rate.
In numerical simulation, concrete material is generally described as a homogeneous material with homogenized material properties derived from standard concrete sample tests[3].
However, concrete is a complex material, consisting of aggregates bounded by cement past, which makes the mechanical behavior of concrete rather complicated.
The reason is that different material properties of the three phases inside the concrete specimen affect the stress wave transportation.

Introduction With the applying of the linear shaped charge in blasting engineering, more and more scholars are interesting in study the factors which can influence on linear shaped charge jet, and want to set up the theory foundation.
With the character of the vary rate of clad thickness, the different results of linear shaped charge jet penetration affected by rock types are analyzed.
*MAT_HIGH_EXPLOSIVE_BURN [2,3]and *EOS_JWL are used to depicting the inherent characteristics and dynamic properties of the TNT.
However, there are different physical and mechanical properties among these rocks, so the best linear shaped charge is changed.
Conclusions During simulating the full process of linear shaped charge jet with eight kinds of uneven thickness clad penetrate the different rocks, and discussing the phenomenon of cracks formation and propagation under the impact of linear shaped charge jet with uneven thickness clad, there are several important propositions as follow: Considering structures of the linear shaped charges and physical and mechanical properties of rocks, it is shows that the longest crack is found in Gneiss, the shortest crack is found in Iron ore and the crack length of Granite is in between.

In linear fracture mechanics, stress intensity factors used to evaluate the crack deformation behavior are calculated by stress distribution around the cracks[3].
The material used here was medium carbon steel S45C (be equal to No.45 steel in China).The chemical composition and mechanical properties are shown in table 1 and table 2 individually.
Mechanical properties Figure 1.
First, mode Ⅰstress intensity factors, (KⅠ)mes measured from fatigue pre-crack are smaller than KⅠbecause the compressive residual stress exists around it.
Mode Ⅱstress intensity factor (KⅡ)mes was also affected because of the zigzag pattern of the crack surface for the fatigue pre-crack.

Moreover, the use of SCMs will adjust the hydration and mechanical properties of cement[4,5].
In the early hydration, the calcined clay and limestone adjust the performance of cement by affecting the hydration of cement itself.
These additional hydration products is another reason for the mechanical properties improvement.
Additional hydration products improved the mechanical properties of blends and refined the pore structure
Favier, Impacting factors and properties of limestone calcined clay cements (LC3), Green Materials, 7(2019)3-14

As a support tool of concurrent engineering, DFC is used in the design stage to make designers take account of the manufacturing, assembly, maintenance and other cost factors of life cycle, make an economic evaluation of product technology, timely modify the design according to cost, and finally reduce product cost.
Process diagram includes processing attributes and processing method, which is the main factor affecting the processing time and production cost.
The starting point of cost modeling is higher than cost estimation that we should get predictive value, and also establish function relations to realize optimal matching between these properties and product cost, which is based on analysis of relationship between some attributes and cost changes.
The disadvantage of this approach is that the selection of the hidden layer is less scientific, and need to be determined after a spreadsheet. (4)Multi-agent cost estimate: The cost is line decomposed according to the influenced factors.
Mechanical Engineering Journal Vol32(1996), No4,pp.63-67 (in Chinese)

Polymer nanocomposites are a class of materials that combine electrical, thermal, dielectric, magnetic and/ or mechanical properties, which are useful for the suppression of electromagnetic interference.
In a nanocomposite, fillers are nanometrics and show large interfacial area per volume, which leads to significant changes in their properties [1] such as electrical and electromagnetic properties that are required for EMI shielding.
These results can be improved by adding a magnetic phase such Cobalt to reinforce the magnetic properties of the slabs.
Summary In this work, we reported on the structural and electromagnetic properties of nanostructured Cu powders by high- energy mechanical milling process.
Shi, ‘’Effects of nanoparticles on the thermal and mechanical properties of epoxy coatings’’, Journal of Nanoscience and Nanotechology, vol.16(2016) pp.9874-9881

The GDK and PKN hydraulic fracture models established by Geertgma, Perkins and so on[3-5] lay the foundation for hydraulic fracture design and fracture propagation analysis, and domestic scholars have studied the mechanism of hydraulic fracturing from the angle of coal and rock physical and mechanical properties, ground stress, control factors and so on, which have provided theory support to solve the problem of coal seam hydraulic fracturing.
Because of the differences of coal seam occurrence condition, physical and mechanical properties and stress environment, crack condition, extension rule and the fracturing effect of hydraulic fracturing are also different.
According to upper equation, it can be known that the influence factors of initial fracturing stress of soft coal seam are mainly Elastic modulus, Poisson's ratio, internal friction Angle, residual strength, deformation and the selected yield criterion.
And these factors’ effect weight to initial fracturing stress must exist discrepancy.
To have a more intuitive understanding of the upper influence factors, the author set the physical and mechanical parameters of 7# coal seam in certain coal mine as calculation basis, and has an analysis to the established calculation formula of initial fracturing stress in the essay.

Therefore, microscopic models of asphalt mixture can include most of the important factors that govern the performance of asphalt mixture.
Damage and anisotropy are important micro-structural factors that influence the macroscopic behavior of granular materials (e.g.
To account for these two factors, it was necessary to multiply the measured binder stiffness by a factor to obtain the stiffness of the mastic.
Dai [4] presented 2D and 3D micromechanical finite element (FE) models to predict the viscoelastic properties.
Micromechanical analysis of viscoelastic properties of asphalt concretes.

There are two common categories of binder jetting process paramters First, material related factors and secondly process related factors. 6.
Saxena, “Influence of Severe Metal Forming Processes on Microstructure and Mechanical Properties of Mg alloys,” Adv.
Brostow, “Physical and Mechanical Properties of Polymer Composites with High Content of Wastes Including Boron,” Mater.
Lee, “Preparation of Fly Ash/Epoxy Composites and its Effects on Mechanical Properties,” Polymers (Basel)., vol. 12, no.1, (2020) p.79
Li, “Development of sheet metal forming dies with excellent mechanical properties using additive manufacturing and rapid tooling technologies,” Int.

All these factors affect the stability of building structures.
Therefore, computational methods for determining fire resistance are of great importance, in which one can try to take into account, if not all, then at least the most important factors affecting the result [3, 4, 5, 6, 7].
One of these important factors is the presence of cracks.
Accidental cracking in reinforced concrete structures can occur as a result of either mechanical or thermal impact (when the concrete temperature exceeds the critical temperature) or a combination of these factors.
[15] Anders Hösthagen, Thermal Crack Risk Estimation and Material Properties of Young Concrete Division of Structural and Fire Engineering.