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Introduction Power transformer as an important device, which directly affects the safety of the power grid reliability, with the continuous expansion of the transformer, the transformer voltage level constantly rising, 500kV, 750kV, 1000kV large-capacity transformer should be shipped out.
With the complex internal structure of the transformer and the influence of insulating material physical properties, the problem of short-circuit strength has become the main reason to cause the transformer accident and acquired more and more attention.
Then the static magnetic force of disk can be derived as follows: (1) Where is the asymmetrical short-circuit current impact factor, is the flux density of th element conductor, is the distance from the centerline of core to the center of gravity of th element conductor, is the symmetrical short-circuit current density of th element conductor, is the area of th element conductor.
When a short circuit occurred in the voltage zero-crossing instant, the short-circuit current will reach to the maximum amplitude value, therefore, short electromagnetic force with the changes of time can be given as follows: (3) Where is the factor to determine the short-circuit force, is the amplitude of the steady-state short-circuit current, is the time constant of circuit, is the grid frequency.
Short Circuit Mechanical Force Withstand Capability Test.

Initial (early age) cracking, induced by changes of the cement paste microstructure, as a result of differential volume changes and moisture flow, could result in structure collapse in the late phases of construction life[1]. and exposure to exterior environmental factors (drying, rate of drying, or freeze and thaw), are important factors, that play a role in the C-S-H formation.
Usually applied to examine metal structures, AE can be used in concrete to detect cracks and crack growth as a result of the concrete property to absorb and transmit sound waves.
Only transport properties such as viscosity will be influenced by the choice of the collision rule.
In order to investigate how the size of solids and their position affect the moisture flow and later on, possibly cracking, different sizes of solid-clusters are created.
Typical AE measurements were performed in the solid under the mechanical load In the mentioned AE test .the only present “load” was moisture in the sample.

Material Properties The material of interest in this work is SCMV, a high strength alloy steel with the composition as shown in Table 1.
An appropriate set of material properties is required to represent the material for use in the numerical models.
Presented below are the material properties used and the corresponding equations for implementation.
Thermal Properties.
Figure 1: Relationship of heat capacity and thermal conductivity with temperature (1) (2) where is heat capacity (J/kg.K), is thermal conductivity (W/m.K) and T is the temperature (K) Mechanical Properties.

Taking into account the differences between modern building materials and technologies from materials and technologies used in the construction of architectural monuments, the problems of the correct choice of raw materials, the use of various additives to control the formation of their structure, improve properties and disassembly modified mortars, similar to historical ones, are being studied along with conducting scientific research to increase the strength, adhesion and durability of solutions.
Another major factor in the resulting poor quality repairs is the neglect of the raw materials used in these repairs.
It is known that the main physical-mechanical and physical-chemical properties of mortars and masonry cements are directly dependent on the chemical, mineralogical and fractional compositions of the initial components used, the ratio of the amount of the main oxides and minor oxides contained in them, and, consequently, on the chemical compositions raw materials from which the final product is obtained.
At one time, the lower part of the wall was in a buried state for a long period, because of it, aggressive factors of the filled-in soil affected it.

The dynamics and emission properties of structural defects were studied by an all-optical pump-probe method of imaging spectroscopy.
A different approach is used in the present study, which aims at clarifying the influence of H-implantation on SF formation, including both passivation and irradiation damage factors.
More specifically, hydrogenation effects were assessed from a direct comparison of the SF dynamics and luminescence properties measured under identical conditions (simultaneously) in virginal and irradiated areas.
It is commonly assumed that residual mechanical stress and growth defects are the major precursors for SF formation.
Considering the low implantation energy chosen to minimize damage and the µm-scale diffusivity of hydrogen, passivation is expected to affect only those SF nucleation sites that are located close to the surface.

The Simulation of Rolling Lamination Forming for a Light Conveyor base on ANSYS/LS-DYNA HE Jian Yun1,a, DING Yu Mei1,b, XUE Zi Chen1,c, YANG Feng1,d, YU Hai Long1,e and YANG Wei Min1,2,f 1College of Mechanical and Electrical Engineering, Beijing University of Chemical Technology, Beijing 100029, China 2State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China ajyhe@mail.buct.edu.cn, bdingym268@gmail.com, cqq383298710@gmail.com, dfengy@mail.buct.edu.cn, eyhldsg_512@126.com, fyangwm@mail.buct.edu.cn Keywords: light conveyor; rolling lamination process; numerical simulation; polyvinylchloride; plastic deformation; Abstract.
There were many factors that affected the quality of the roll compound forming part, the shape of the mold, process parameters and material properties levels had different degrees of influence on the quality of the roll compound forming part.
In order to avoid the generation of negative volume, the grid was divided relatively small and the factor of time step was set even more small (0.5 or less).
Duncan, Fundamental deformation types and sectional properties in roll forming, Int.

Zhao et al. [14] analyzed the effects of various factors such as the test pressure inside the casing, the crustal stress, the cement sheath thickness, the elastic modulus and Poisson’s ratio of the set cement and other factors on the integrity of the cement sheath under stress.
They found that the Young’s modulus of the cement sheath was the main factor affecting the sealing performance, while the Poisson’s ratio and the cohesion of cement were also important.
The results showed that the above factors had strong influence on the distribution of Von Mises stress in the inner wall of the innermost casing.
Fig. 1 Schematic diagram of the formation-cement Fig. 2 Annotation of the first, sheath-casing combination second interfaces and casing 2.2 Physical Properties of the Formation, the Cement Sheath and the Casing The physical properties of the formation, the cement sheath and the casing are summarized in Table. 1.
Evaluation of mechanical well integrity during CO2 underground storage.

Engineering Geological Characteristics of Aeolian Sand The aeolian sand that concentrated at the top of Shenmu tunnel is composed of the feldspar, quartz sand, silt and silt soil, of which the coating thickness is 15~35m.The physical and mechanical properties of aeolian sand layer are in Tab.1, the distribution of particle size distribution in Tab.2 [1-2].
The Project of Field Grouting Experiment According to the basic properties of grouting materials, combined with the engineering geological conditions of the aeolian sand in Shenmu tunnel and the importance level of grouting, using permeation grouting and whirling jet grouting methods, the field grouting experiments were carried out using the grouting materials that include portland cement, superfine cement and modified sodium silicate.
Tab.3 Physical index of modified sodium silicate reinforcement Water content(%) Weight (N/m3×104) Compression factor(MPa-1×10-3) Compression modulus (MPa) Internal friction angle(°) Cohesion (MPa) void ratio 17.33 1.24 1.3 13.15 25.31 0.05 0.751 The test blocks were produced to test their physical and mechanical properties, which were mixed the modified sodium silicate with sand.
The grouting pressure and slurry consistency affect the compaction of the backfill.
Therefore, it is no sense to increase water-cement ratio to improve the flow properties of the slurry.

Giant magnetostrictive materials have a broad potential application in aviation and aerospace field owing to its good properties.
Some researches have been done to improve the GMA’s positioning accuracy affected by highly nonlinear, hysteretic behavior of giant magnetostrictive material and the accuracy of the control instruments.
Mechanical prestress is introduced to orient current magnetic domains to the compression axis, maximizing displacement.
Mechanical prestress is introduced to orient current magnetic domains to the compression axis, maximizing displacement.
Yang, Review of mechanical structure of micro-displacement actuator for optical astronomical telescope, Prog.

Bioplastics molecular chains can break down into smaller particles due to the biological the changes in their properties [12].
To address the need for environmentally friendly radiation shielding, researchers have explored bioplastic composites with enhanced mechanical properties.
The exposure factors used during this research were 60 kV, 204.4 mA, 18.1 ms and 100 cm.
Tchirioua, Influence of natural factors on the biodegradation of simple and composite bioplastics based on cassava starch and corn starch, Journal of Environmental Chemical Engineering. 8. 104396 (2020). https://doi.org/10.1016/j.jece.2020.104396
Purbasari, and Kusmiyati, The effect of composition on mechanical properties of biodegradable plastic based on chitosan/cassava starch/PVA/crude glycerol: Optimization of the composition using Box Behnken Design, Material Today: Proceedings. 63.