scholarly journals Analysis of the Mechanical Characteristics of Bolts under Roof Separation Based on Exponential Function

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Xiao Ding ◽  
Shuan-Cheng Gu
Keyword(s):  
Exponential Function ◽  
Coal Mine ◽  
Load Transfer ◽  
Reference Value ◽  
Hyperbolic Function ◽  
Underground Engineering ◽  
Distribution Form ◽  
Support Engineering ◽  
Bedded Rock ◽  
Bolt Reinforcement

With regard to the excavation of coal mine tunnels, the phenomenon of roof separation frequently occurs owing to the deformation of roadway surrounding rocks, and the analysis of the influence of surrounding rock separation on bolt reinforcement plays an indispensable role in the security of support engineering. In the present paper, the hyperbolic function model of bolt load transfer is simplified to the exponential function form, and the simplified distribution form is modified by error analysis. Drawing on the analytic model of elastoplastic mechanics of bolt load through separation, this paper further investigates the influence of separation development on bolt load and conducts the parametric analysis of the separation value and separation position. Finally, taking the separation effect into consideration in the anchorage design of coal mine, practical reference value has been attached to the supporting design of underground engineering in bedded rock mass.

Feasibility Analysis on Implement of Freeze Roadway Cooling Technology in Coal Mine of Heilongjiang Province

2012 ◽  
Vol 204-208 ◽  
pp. 1830-1833
Author(s):  
Jing Zhou ◽  
Xi Ming Liu ◽  
Xian Li Qin ◽  
Shu Ren Xing
Keyword(s):  
Constant Temperature ◽  
Coal Mine ◽  
Soil Layer ◽  
Reference Value ◽  
Frozen Soil ◽  
Feasibility Analysis ◽  
Geological Condition ◽  
Heilongjiang Province ◽  
Geographical Position ◽  
Cooling Technology

Freeze roadway cooling technology is delivering cold quantity to cooling underground face by storage cooling energy in strata, and the effect of storaging cold is critical. The geographical position and geological condition of coal mine in Heilongjiang Province has remarkable characteristics. The feasibility of freeze roadway cooling measure was demonstrated on temperature, geothermal, constant temperature strata and frozen soil layer, etc. by analyzed its advantage adequately. The measure provides a new idea which suits the native situation for prevent the heat-harm in coal mine, it also has the realistic reference value and is worth popularizing.

Horizontal Well Penetration Rate Increasing Technology in Sulige Gas Field

2015 ◽  
Vol 733 ◽  
pp. 17-22
Author(s):  
Yang Liu ◽  
Zhuo Pu He ◽  
Qi Ma ◽  
Yu Hang Yu
Keyword(s):  
Horizontal Well ◽  
Economies Of Scale ◽  
Reference Value ◽  
Drilling Speed ◽  
Underground Engineering ◽  
Gas Field ◽  
Horizontal Section ◽  
Well Drilling ◽  
Drilling Parameters ◽  
Key Techniques

In order to improve the drilling speed, lower the costs of development and solve the challenge of economies of scale development in sulige gas field, the key techniques research on long horizontal section of horizontal well drilling speed are carried out. Through analyzing the well drilling and geological data in study area, and supplemented by the feedback of measured bottom hole parameters provided by underground engineering parameters measuring instrument, the key factors restricting the drilling speed are found out and finally developed a series of optimum fast drilling technologies of horizontal wells, including exploitation geology engineering technique, strengthen the control of wellbore trajectory, optimize the design of the drill bit and BHA and intensify the drilling parameters. These technologies have a high reference value to improve the ROP of horizontal well in sulige gas field.

Exponential function for calculating saturable enzyme kinetics.

1988 ◽  
Vol 34 (12) ◽  
pp. 2486-2489 ◽  
Author(s):  
F Keller ◽  
C Emde ◽  
A Schwarz
Keyword(s):  
Steady State ◽  
Enzyme Kinetics ◽  
Exponential Function ◽  
Association Constant ◽  
Time Dependent ◽  
Mathematical Representation ◽  
Hyperbolic Function ◽  
Maximal Velocity ◽  
Michaelis Constant ◽  
General Meaning

Abstract Enzyme kinetics are usually described by the Michaelis-Menten equation, where the time-dependent decrease of substrate (-dS/dt) is a hyperbolic function of maximal velocity (Vmax), Michaelis constant (Km), and amount of substrate (S). Because the Michaelis-Menten function in its most general meaning requires an assumption of steady-state, it is less curvilinear than true enzyme kinetics. A saturation-type exponential function is more curvilinear than the hyperbolic function and more closely approximates enzyme kinetics: -dS/dt = Vmax [1 - exp(-S/Km)]. The mathematical representation of enzyme kinetics can be further improved by introducing a deceleration term (Vdec), to make the assumption of a steady state unnecessary. For the action of chymotrypsin on N-acetyltyrosylethylester, the Michaelis-Menten equation yields the following: Vmax = 3.74 mumol/min and Km = 833 mumol. According to decelerated enzyme kinetics, the values Vmax = 4.80 mumol/min, Vdec = 0.0118 mumol/min, and the association constant (Ka) = 0.00111/mumol are more nearly accurate for this reaction (where 1/Ka = 901 mumol approximately Km).

Study on the Analysis of Secondary Anchoring Mechanism and Effective Distance

2011 ◽  
Vol 71-78 ◽  
pp. 4014-4019
Author(s):  
Lai Wang Jing ◽  
Li Ping Ye ◽  
Peng Wei Hao ◽  
Ke Xiu Zhao
Keyword(s):  
Coal Mine ◽  
Elastoplastic Deformation ◽  
Soft Rock ◽  
Reference Value ◽  
Fem Analysis ◽  
Effective Distance ◽  
Exact Data ◽  
Use For Reference ◽  
Face Support

The paper is intent to open out the mechanism and effective distance of secondary anchoring in coal mine rock laneway support. Though the analysis of elastoplastic deformation, caused by heading face support removing in laneway development, the paper explained that secondary anchoring is necessary and important to rock laneway, and relatively exact data were given by FEM analysis. The paper illustrated a special example, and put it up with meticulous analysis, the results were not only having important reference value to coal mine soft rock laneway support, but also having definite use for reference to other mine soft rock laneway support.

scholarly journals Research on Bearing Theory of Squeezed Branch Pile

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hong-wei Ma ◽  
Yi-ying Wu ◽  
Yu Tong ◽  
Xiao-qiang Jiang
Keyword(s):  
Load Transfer ◽  
Theoretical Method ◽  
Shear Displacement ◽  
Theoretical Research ◽  
Hyperbolic Function ◽  
Displacement Method ◽  
Practical Engineering ◽  
Nonlinear Relation ◽  
Shear Displacement Method ◽  
Homogeneous Soil

Based on the shear displacement method, theoretical research on the load transfer relation of squeezed branch pile is established. In combination with the nonlinear relation of the interaction between piles and soil, the hyperbolic function is used to describe the pile tip, pile skin, and branch. The theoretical method of the load transfer is improved, and the expression of the load transfer coefficient of these three parts is given. Finally, the applicability of the theoretical method is verified by the model test of homogeneous soil and the field test of stratified soil. The verification results show that the theoretical calculation method of the squeezed branch single-pile bearing capacity based on the shear displacement method can better calculate the ultimate load in practical engineering applications.

scholarly journals In Situ Test Research on Friction Resistance of Self-Anchored Test Pile

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Chi Chen ◽  
Hailong Ma ◽  
Bilian Yang
Keyword(s):  
Transfer Process ◽  
Load Transfer ◽  
Test Method ◽  
Hyperbolic Function ◽  
Function Model ◽  
In Situ Test ◽  
Testing Method ◽  
Pile Testing ◽  
Test Pile

The traditional static load test method has been considered as the most direct and reliable method to determine the bearing capacity of single pile, but it has some disadvantages, such as inconvenient operation, laborious test, high cost, and being time-consuming. In this paper, a new type of pile testing method, self-anchored pile testing method, was proposed, and the in situ test was carried out for the first time. This method allows the upper and lower piles to provide force to each other and does not occupy other construction spaces. It had the advantages of simple operation and being economical and practical. Based on the Q-w curve, axial force distribution curve, and hyperbolic function model of load transfer, this paper studied the evolution law of friction of self-anchored test pile and the load transfer process of self-anchored test pile. The results show that the load transfer process of self-anchored pile-soil interface can be divided into three stages: elastic, elastic-plastic, and limit state. The friction of the upper and lower piles starts from the bottom of each pile and then gradually increases. The soil around the upper and lower piles gradually undergoes nonlinear deformation and shear failure, and the pile soil reaches the yield state. By analyzing the hyperbolic function model of load transfer, it shows that the hyperbolic function model can be better applied to the self-anchored test pile, which has reference value for the selection of the function model of self-anchored test pile in the future.

Study on the Supporting Method of Crossheading in Shallow-Buried Coal Seams Working Face Using FLAC Simulation

2013 ◽  
Vol 275-277 ◽  
pp. 1564-1568
Author(s):  
Jian Feng Luo
Keyword(s):  
Coal Mine ◽  
Field Tests ◽  
Reference Value ◽  
Working Face ◽  
Site Monitoring ◽  
Deformation Law ◽  
Before And After ◽  
Safety Production ◽  
Northern Shaanxi ◽  
Seam Mining

Taking 1403 coal face of Fengjia coal mine in northern Shaanxi as background, put forward three supporting schemes of crossheading according to different buried depth and coal seam interval. Applying FLAC software, established relevant calculating model, analyzed the stress field and surrounding rock deformation caused by shallow seam mining before and after supporting. Combining the result from site monitoring, obtained the deformation law of crossheading surrounding rocks in the short distance seam: the vertical deformation is the main deformation under the A support scheme. The field tests showed that: the supporting schemes according to the section of crossheading is feasible and it ensured haulage gate roadway’s surrounding rocks stability , met the requirements of safety production in the coal mine, the supporting schemes of crossheading proposed in this paper has reference value to similar project.

Analysis on Deformation and Support Technology of Deep Soft Rock Roadway

2014 ◽  
Vol 580-583 ◽  
pp. 556-559
Author(s):  
Yong Sheng Liu ◽  
Wang Liu ◽  
Xing Yu Dong
Keyword(s):  
Coal Mine ◽  
Soft Rock ◽  
Reference Value ◽  
Roadway Deformation ◽  
Soft Rock Roadway ◽  
Rock Roadway

The deformation and support technology of soft roadway is a very important problem in mine. Based on the roadway’s deformation of Jian Xin Mine of Jiangxi Fengcheng Mining Bureau, the mechanics mechanism and reasons of the soft rock roadway deformation are analyzed. And the three kinds of support technologies which are suitable for soft rock roadway are put forward. The support technologies have been used in the soft rock roadway of coal mine and have achieved good results. The research has important reference value for soft rock roadway supporting technology and its stability maintenance.

scholarly journals Application of the Multiple Exp-Function, Cross-Kink, Periodic-Kink, Solitary Wave Methods, and Stability Analysis for the CDG Equation

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Haifa Bin Jebreen ◽  
Yurilev Chalco-Cano
Keyword(s):  
Stability Analysis ◽  
Exponential Function ◽  
Periodic Wave ◽  
Hyperbolic Function ◽  
Kink Solution ◽  
Engineering Sciences ◽  
Hirota Bilinear Form ◽  
The Stability ◽  
Wave Methods ◽  
Selection Of

In this article, the exact wave structures are discussed to the Caudrey-Dodd-Gibbon equation with the assistance of Maple based on the Hirota bilinear form. It is investigated that the equation exhibits the trigonometric, hyperbolic, and exponential function solutions. We first construct a combination of the general exponential function, periodic function, and hyperbolic function in order to derive the general periodic-kink solution for this equation. Then, the more periodic wave solutions are presented with more arbitrary autocephalous parameters, in which the periodic-kink solution localized in all directions in space. Furthermore, the modulation instability is employed to discuss the stability of the available solutions, and the special theorem is also introduced. Moreover, the constraint conditions are also reported which validate the existence of solutions. Furthermore, 2-dimensional graphs are presented for the physical movement of the earned solutions under the appropriate selection of the parameters for stability analysis. The concluded results are helpful for the understanding of the investigation of nonlinear waves and are also vital for numerical and experimental verification in engineering sciences and nonlinear physics.

scholarly journals Coordinate-free exponentials of general multivector in Cl(p,q) algebras for p+q=3

2021 ◽  
Author(s):  
Arturas Acus ◽  
Adolfas Dargys
Keyword(s):  
Signal Processing ◽  
Differential Equations ◽  
Automatic Control ◽  
Closed Form ◽  
Exponential Function ◽  
Free Form ◽  
Hyperbolic Function ◽  
Main Difficulty ◽  
Geometric Algebras ◽  
And Robotics

Closed form expressions in real Clifford geometric algebras Cl(0,3), Cl(3,0), Cl(1,2), and Cl(2,1) are presented in a coordinate-free form for exponential function when the exponent is a general multivector. The main difficulty in solving the problem is connected with an entanglement (or mixing) of vector and bivector components a and a in a form (a-a), i≠ j≠ k . After disentanglement, the obtained formulas simplify to the well-known Moivre-type trigonometric/hyperbolic function for vector or bivector exponentials. The presented formulas may find wide application in solving GA differential equations, in signal processing, automatic control and robotics.

Sign in / Sign up

Export Citation Format

Share Document