scholarly journals Predictive assessment of the stability of quarry sides

2021 ◽  
Vol 6 (2) ◽  
pp. 201-210
Author(s):  
A. V. Volokhov

The composition of the rocks composing the quarry sides and the approximate slope angles in accordance with the mining and geological conditions are described. The issues of creating observation stations are considered taking into account seasonal temperature fluctuations of the benchmarks. Observation materials are generalized, the degree of danger of deformations is established on the basis of observations of deformation speed. The mining safety control methods are described. The disadvantages of the approach to data processing and analysis are identified. A criterion for mine surveying prediction of the pit wall stability based on the comparison of critical and actual relative deformations is proposed. The purpose of the local forecast of wall deformation is to control the stability of non-working and working slopes of the sides, and to confirm the efficiency of the method used. The predictive assessment was carried out on the shift of working benchmarks on one of the open pits of Transbaikalia. It is suggested monitoring the stability of rocks using oscillograms obtained by seismic equipment. 

2014 ◽  
Vol 962-965 ◽  
pp. 1075-1078
Author(s):  
Shao Jie Feng ◽  
Xue Fang Zhao ◽  
Shi Guo Sun

The stress of slope is in dynamic changes from open-pit to underground of the mining excavation . In this article, based on the relationship of space corresponding through the two mining methods, and two types of mining influence dominated overprint and containing characteristics, it can find out its regularity according to the numerical simulation, and also can reveal the induced with mutual interference between two excavation system mechanism, deformation of foundation and its numerical size out of dangerous area from the mining effect of interaction and mutual superposition characteristics; On this basis, it also analyzes its influence on the stability of the slope characteristics and deformation law, and puts forward to the control methods which provide the decisions basis for the mining safety production.


2019 ◽  
Vol 136 ◽  
pp. 04023
Author(s):  
Ming Zhao ◽  
Ke Li ◽  
Hong Yan Guo ◽  
KaiCheng Hua

Based on the special geological conditions of a tunnel in Qingyuan section of Huizhou-Zhanzhou Expressway, FLAC3d numerical simulation software is used to simulate the rheological properties and instability of surrounding rock in large-section fully weathered sandstone section, and the stability and loss of surrounding rock are analyzed. The deformation of the dome and the face at steady state is analyzed. It is found that: 1) when the surrounding rock is in a stable state, the deformation curve of the dome is smooth. When the surrounding rock of the face is unstable, the front of the face appears ahead. Deformation should be first strengthened on the surrounding rock in front of the face. 2) The arched foot is an important part of the instability of the surrounding rock. In order to prevent the expansion of the collapsed part, the arched part should be reinforced. 3) In order to obtain the limit state of surrounding rock stability, the strength of surrounding rock is reduced, and the strength reduction coefficient corresponding to the displacement sudden point is taken as the safety factor of rock stability around the hole, and the stability safety coefficients of surrounding rock of each construction step are greater than 1.2. 4) The dynamic standard values of deformation control in the whole construction stage are obtained by analyzing the deformation curves of each data monitoring point with time in the corresponding time period of each construction step.


2014 ◽  
Vol 608-609 ◽  
pp. 19-22
Author(s):  
Ping Xu ◽  
Jian Gang Yi

Hydraulic descaling system is the key device to ensure the surface quality of billet. However, traditional control methods lead to the stability problem in hydraulic descaling system. To solve the problem, the construction of the hydraulic descaling computer control system is studied, the working principle of the system is analyzed, and the high pressure water bench of hydraulic descaling is designed. Based on it, the corresponding computer control software is developed. The application shows that the designed system is stable in practice, which is helpful for enterprise production.


Author(s):  
Gao Ming-Zhou ◽  
Chen Xin-Yi ◽  
Han Rong ◽  
Yao Jian-Yong

To suppress airfoil flutter, a lot of control methods have been proposed, such as classical control methods and optimal control methods. However, these methods did not consider the influence of actuator faults and control delay. This paper proposes a new finite-time H∞ adaptive fault-tolerant flutter controller by radial basis function neural network technology and adaptive fault-tolerant control method, taking into account actuator faults, control delay, modeling uncertainties, and external disturbances. The theoretic section of this paper is about airfoil flutter dynamic modeling and adaptive fault-tolerant controller design. Lyapunov function and linear matrix inequality are employed to prove the stability of the proposed control method of this paper. The numeral simulation section further proves the effectiveness and robustness of the proposed control algorithm of this paper.


2021 ◽  
Author(s):  
Barkane Aicha ◽  
Sami Mezhoud

Abstract The response of a massif to stresses generated by tunnel excavation depends essentially on the geological conditions, the geometry of the tunnel and its underground position. The major problem related to the construction of these structures is to ensure the stability of the whole tunnel-ground, by controlling the various deformation generated during the constructionIn this context, the present paper examines the effect of these conditions on the behavior of tunnels and the surrounding soil. The study is applied to a real tunnel, in this case the tunnel of Djebel El Ouahch, Algeria was taken as a reference model. The research includes a parametric study to evaluate the effect of several parameters on the behavior of the tunnel and surrounding soil such as the tunnel anchoring depth, the tunnel-soil interface rate, and the shape of the tunnel cross section. The analysis is performed using the PLAXIS 3D TUNNEL calculation code with an elastoplastic Mohr-coulomb model for the soil behavior. The results show that the strongest and most stable position is the mid-deep tunnel with a circular section, with a non-slip interface between the tunnel and the ground. These outcomes can help to understand the effects of various influences parameters which control the stability of the tunnel in a soil with bad characteristics.


2020 ◽  
Vol 5 (2) ◽  
pp. 30-43
Author(s):  
Bagas Setyadi ◽  
Rustadi Rustadi

Bandar Lampung is one of the cities in Indonesia, which has a potential to land subsidence due to the extraction of ground water, mining, land conversion, and geological conditions. For that reason, carried out the study of land subsidence with SBAS technique, due to the very lack of information about the symptoms of land subsidence in Bandar Lampung. In this study, 15 SAR data in 2006 to 2011 used and then combined to produce 40 interferogram then inverted resulting in a time-series deformation and deformation speed average. Velocity precision obtained with SBAS technique is highly dependent on the type of land cover in the study area, but it is known that the average of land subsidence in Bandar Lampung is about 0.06 mm/year, which is considered quite stable due to the geological structure that does not allow for the occurrence of massive consolidation process. Several areas have indications of subsidence 5 mm/year are suspected to be caused by tectonic activity and human activity (industrial, mining, extraction of groundwater, and land conversion), which then has implications for structural damage to buildings, flooding in coastal areas, and landslides in hilly areas.


2012 ◽  
Vol 57 (1) ◽  
pp. 193-208 ◽  
Author(s):  
Petr Horyl ◽  
Richard Šňupárek

Due to the strong impacts of rockbursts in Ostrava-Karvina coalfield, which affect especially roadways and cross-cuts of longwall panels, it is necessary to strengthen standard steel roadways and breakthroughs supports. However it is a little different task in comparison with main solved problems of mining safety (Kidybinski, 2011), the use of reinforcing complementary bolts seems to be very effective. A varieties of numbers and locations of such rockbolts have been analyzed and compared from the viewpoint of the stability under dynamic events on the base of 3D mathematic modeling. The method used for computer modeling has been FEM applied by ANSYS code. It deals with the shape and nature the following issues: the deformation of a steel support, strain and deformation of reinforcing bolts, the critical energy by which a permanent strain is caused and the influential interaction of the adjacent rock on the above mentioned characteristics. A recommendation for number and location of reinforcing complementary bolts is also contained.


2020 ◽  
Vol 8 (4) ◽  
pp. 291
Author(s):  
Hu Wang ◽  
Jian Chen ◽  
Hongjun Liu ◽  
Lei Guo ◽  
Yao Lu ◽  
...  

In the construction of subsea tunnels, the stability and control of the excavation surface are the main concerns of the engineering community. In this paper, the Xiamen Metro Line 2 is used as the study case. The filter cake formation of mud shields is experimentally studied, and the excavation surface is numerically simulated. It is found that the formation of filter cake does not require a large pressure difference, and can be formed under 0.06 MPa. With the increase of pressure, the quality of filter cake is further improved, and a small amount of seawater (volume ratio less than 3%) also has a significant effect on the viscosity of mud. Under different cross-section geological conditions, with the decrease of the support pressure of the excavation face, the vertical displacement and vertical (Y-direction) displacement of the excavation face dome gradually increase, the maximum longitudinal displacement is 9.7 mm, the maximum longitudinal displacement can reach 23.9 mm, and the growth trend is nonlinear. According to different stratum conditions, during the excavation of the tunnel, the plastic area of the excavation face is different.


2020 ◽  
Vol 2020 ◽  
pp. 1-18 ◽  
Author(s):  
Yang Yu ◽  
Dingchao Chen ◽  
Xiangqian Zhao ◽  
Xiangyu Wang ◽  
Lianying Zhang ◽  
...  

With the increase of mining intensity of coal resources, some coal mines in China have gradually entered the deep mining stage. The complexity of the stress environment of the deep rock stratum leads to the difficulty of coal mining. Among them, the control of the deep roadway is one of the bottlenecks restricting the safety mining of the deep coal resources in China. By means of statistical analysis, the factors affecting the stability of the deep roadway were summed up: roadway occurrence environment, driving disturbance, and support means. The mechanical model of the deep roadway was established with the theory of elastic-plastic mechanics, the distribution characteristics of the plastic zone of the roadway were revealed, and the influence laws of lateral pressure coefficient, vertical stress, and support strength on the stability of the roadway were analyzed. Through numerical simulation, the law of stress, displacement and the plastic zone distribution evolution of the deep roadway, the mechanism of horizontal stress, and the mechanism of bolt support on the roadway were studied. On this basis, the safety control strategies to ensure the stability of the deep roadway were put forward: improving the strength of the roof and floor, especially the bearing part of the top angle and the side angle, enhancing the stability of the two sides of the roadway and controlling the floor heave, and making the surrounding rock of the deep roadway release pressure moderately, so as to make the roadway easy to be maintained under the low stress environment. These meaningful references were provided for the exploitation of deep coal resources in China.


Sign in / Sign up

Export Citation Format

Share Document