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Our study aims to investigate the mechanical behaviour of concrete under homogeneous conditions of moisture and temperature.
BMacena Unit Quantity CEM I 52,5 N CE CP2 NF (Gaurain) kg/m3 320 Sand 0/4 roulés silico-calcaire (Varennes) kg/m3 830 Gravel 4/11 roulés silico-calcaire (Varennes) kg/m3 445 Gravel 8/16 roulés silico-calcaire ( Balloy) kg/m3 550 Superplasticizer SIKAPLAST 80 kg/m3 2.75 Total water kg/m3 197.6 E/C 0.62 The standard mechanical properties of the hardened concrete at 28 and 90 days are reported in Table 2.
These properties were obtained by calculating the mean of two samples for each case performed on 16 x 32 cm specimens.
Indeed, this shape serves to minimize the volume of the device, an important factor for carrying out tests under pressure with security in a future study.
Fracture energy decreases as the degree of water saturation increases but does not seem to be affected by the temperature (for 30 and 90 °C).

Stay ropes are affected by the environment.
The cross-sectional shape of a stay rope affects its resistance to wind loads.
Paper [33] analyzes mechanical properties of composite materials reinforced by a longitudinal framework of rigid elements.
Not significantly lower maximum loads on reinforcing elements, in a case of using stay ropes with a larger number of reinforcing fibers, indicate a feasibility of using the latter, provided there are no other factors.
DOI: 10.1016/j.ijsolstr.2018.10.023 [28]  Xianguo Li, Xinyu Long, Zhenqian Shen and Changyun Miao (2019)  Analysis of Strength Factors of Steel Cord Conveyor Belt Splices Based on the FEM Advances in Materials Science and Engineering Volume ID 6926413.

Absolute heat source is is heat release from mechanical and electrical equipment, air compressor, chemical reactionthe and workers.
In the formula, is the temperature of the air aground and is the temperature of the air at the shaft bottom, ˚C;is the relative humidity of the air aground and is the relative humidity of the air at the shaft bottom;is the atmosphere pressure aground andis the atmosphere pressure at the shaft bottom,kPa;is the amount of the wind through the shaft,kg/s;is the well depth,m;can be selected from the related charm.is the diameter pf the shaft,m;is the total amount of the heat release from part heat source,kW;,,,,,are the calculated factors which are brought in;other symbols have the same meaning as the previous symbols. 2.2 The thermal calculation model of horizontal,oblique roadway Some of the parameters which affect the heat exchange change as time changes,so it is different to use the formula of airflow temperature.Considering the ventilation time is more than one year,we can get the heat calculation model as follows[6-8]:
（6） （7） （8） The value of the calculated factors and the constant coefficient will be different at different temperature.In this article,we values the factors according to the actual situation as follows: ,,,, , .
design scheme of ventilation system, improve the environment air temperature and finally create a comfortable environment and meet production requirements.Calculation results of airflow temperature in different simulation schemes are as follows: Tab. 1 Calculation results of airflow temperature in different simulation schemes Ventilation time Plan Total air volume (working face air volume)/m3/s Total resistance /Pa The average temperature inthe working face/˚C Easy time Change amount of wind 114.5(25) 2276.0 32.8 119.5(30) 2684.8 31.4 Different roadway to transform coal 118(25) 2459.1 29.0 123(30) 2897.0 27.9 Different roadway to transform coal, increase auxiliary air roadways 123(30) 2394.6 28.0 Difficult time Change amount of wind 129.5(25) 3050.2 41.9 134.5(30) 3710.2 40.3 A system for two back 136.5(25) 3409.8 36.6 141.5(30) 4102.2 34.9 Increase auxiliary air roadways,a system for two back 136.5(25) 3123.60 33.6 Conclusions Based on the analysis of the different properties

HE Ying-jie [6] has systematic study of affecting factors of deformation of conjunction bolts by means of structural model tests of pipe-plate junction with a full scale used for simulating the line of shield-tunneling.
Meanwhile, some scholars studied the mechanical properties of joint by 3D finite element joint model [7-11], and some internal force calculation formulas of joints were brought.
Some study show that [12], the frictional factor of rubber sealing gasket is 0.83, when there is not lubricant on the rubber surface.
According to the above research results, it establishes coulomb Contact friction model with 0.83 frictional factors on the tangential orientation between segments joint.
The loop bolts improve the global property of shield tunnel.

This study aimed to evaluate the impact of the sintering effect of ZCT ceramic oxides on several aspects, including crystal structure, surface morphology, optical properties, and electrical properties.
Because of its exceptional chemical, mechanical, and optical properties, zirconium oxides (ZrO2) have garnered much attention as a significant ceramic material.
This is because high-temperature sintering can alter the crystal structure and composition of the material, affecting its electrical characteristics.
Numerous factors, such as the preparation method and chemical composition, affect the dielectric properties. [40, 41] The equation in is used to get the dielectric constant (εꞌ) in a parallel plate capacitor.
"High-κ gate dielectrics: Current status and materials properties considerations."

The key properties of the copper electrode are presented in Table 1.
The chemical composition of this alloy can be found in Table 2, while Table 3 provides information on its physical properties.
Electrode material properties Electrode material Specific heat capacity (J/g °C) Electrical resistivity (ohm cm) Thermal conductivity (W/cm °C) Melting point (°C) Copper 0.385 1.69 3.91 1083 Table 2.
Physical composition of Hastelloy C276 PROPERTIES Heat capacity (J/ kg °C) Density (g/cm3) Modulus of Rigidity (Gpa) Hardness (HRB) VALUES 427 8.89 205 87 Selection of process parameters Many factors influence machining performance in EDM.
TR = D0 -D12t (4) Where, D0 = Average diameter of hole at entry side (mm) D1 = Average diameter of hole at exit side (mm) t = Thickness of the workpiece (mm) Results and Discussion RSM is a mathematical and statistical tool used to analyse problems where a dependent variable (response) is affected by multiple independent variables (factors).

Introduction Coal pillar width is an important parameter in the design of work-face mining, because a reasonable width can directly determine the mining rate of coal and affect the utility efficiency and maintenance cost of roadways.
Because of the sound condition of occurrence, large mechanical equipment is used in the work-face recovery with a height of about 5 m.
The mining height is 4.8m and footage driving cycle is 0.9m; the one pass mining of large cutting height is adopted on the work-face and fully caving coal mining is used to control the roof. 1-5101work-face；2-Goaf；3-Coal pillar ;4-5101work-face return airway；5-5103 work-face roadway；6-Contact roadway Fig. 1 The roadway layout of work-face Theoretical Calculation To calculate the width of coal pillar is quite a complicated problem, because it can be affected for many factors such as the mining depth, coal-seam thickness, height of roadway and mechanical properties of rock and coal seam.
According to the distribution of bearing pressure along the tilting coal seam, the area which can be greatly affected by the pressure is not at the edge of the coal, but in the area distant from the edge.
It can be seen that when the width is 25m, the stress and stress concentration factor is the minimum; when the width is 20m, they are the second minimum; when the width is 35m, the deformation is the smallest.

Meanwhile, for wire-line coring hydro-hammer drilling, special attention should be paid to maintain the properties stability of drilling fluid, and to deal with the precipitated rock powder and other sundry timely in the circulation system.
The rotating speed is determined mainly in the light of the factors of nature of the rock, drill borehole structure, angle, drilling equipment, tool model, impacting energy and impact frequency.
In fact, rotating speed was far less than the design requirement due to the factors of the complex rock in borehole and equipment capability etc.
Physical and mechanical properties of the rock in testing ore field.
The typical physical and mechanical properties of the rock in testing ore field as is shown in Table 1.

Many factors involved in libraries energy saving, such as air-conditioning systems, lighting systems and other electrical systems.
Lighting has become one of the main factors directly affect the efficiency, therefore, more and more attention aroused.
Design lighting environment based on the luminance of the light, taking the uniformity of the luminance, the degree of glare, the properties of color rendering and the sense of three-dimensional etc.
It can be seen that achieve 82.6% of the lighting energy saving effect, exclude lamp power factor can be achieved 30.3% of the lighting energy-saving effect.
Many factors involved in libraries energy saving, such as air-conditioning systems, lighting systems and other electrical systems.

Introduction Inevitably, the excavation of underground space will produce different degrees of destruction in soil, and ground deformation, especially for shallow tunnel, the large ground deformation will not only result in a tunnel accident, affected areas may also spread to the surface, resulting in surface subsidence and the destruction of surface structures and facilities, making impact and loss to the engineering[1][2].With high-grade highways gradually from the eastern to the western in recent years, the highway tunnel have a huge advantage to overcome terrain obstacles , and shorten the spatial distance in complexly geological background conditions in the western region[3].
Because of the complexity and diversity of the actual situation, even if it is the same construction methods also vary in a similar engineering background, in order to analyze the impact of the construction program works in the same background, also to reduce computation and meet the actual needs of the simulation, necessary to simplify the entire excavation, and focuses on the main factors in the process of simulation, surface displacement during tunnel excavation is the main object in this study.
Combining engineering geological investigation information with specification to ensure physico-mechanical properties of soil, advanced parameters according to [5]: increased physico-mechanical parameters of surrounding rock.
The physico-mechanical properties of initial support and secondary lining structure are calculated according to the equivalent section method described in [6].
Table 1 Physico-mechanical parameters of rock mass and supporting structure Material Severe γ (KN/m3) Elastic modulus E [MPa] Cohesion C [Pa] Internal friction angle φ/° Poisson's ratio v Silty clay 18.7 7.9 4.2×104 22 0.27 Advanced support 21 24.5 6.3×104 24 0.21 Primary support 25 2.8×104 4.2×106 53 0.2 Secondary lining 25 3.0×104 5.0×106 55 0.2 In the calculation, for shallow-buried tunnel, the calculation of initial stress field by weight.