【 Abstract 】 At present, the demand for coal mine resources is increasing, and the supporting technology is often used in the process of coal mine excavation, and the existing problems need to be solved urgently. In view of this, based on many years of working experience, the author analyzes the problems existing in the support of Sino-Thai mining engineering, and puts forward corresponding solutions.
[Keywords:] tunneling support mode; Problems; Countermeasures
introduce
Because coal mining is mostly carried out underground, safety accidents occur from time to time. In order to avoid safety accidents to the greatest extent, it is necessary to take protective measures including tunneling support technology. However, there are still some defects and deficiencies in the excavation support work in China, and it is necessary to better implement relevant measures on the basis of fully studying the coal mine excavation technology. This can not only effectively improve the efficiency of coal mining, but also improve the safety of coal mining.
1 Problems existing in coal mine excavation work
1. 1 The roadway construction section is small.
With the increasing demand of coal mines, the traditional arch tunnel is difficult to support a large number of transportation work in coal mines, which hinders the work of miners. Sometimes these obstacles will cause serious mine accidents, which seriously threaten the life safety of construction workers and increase the social burden. Moreover, the cross section of the roadway designed by Zhongtai Mining is smaller, less than12m2. It is difficult to use large-scale tunneling equipment, which leads to the inability to significantly improve the tunneling level, thus affecting the economic benefits of the mine; On the other hand, the traditional small-section roadway can not effectively meet the requirements of the integration of locomotive and rail, and is not conducive to mine ventilation, so that the roadway can not play its greatest role.
1.2 coal mine support technology is backward.
At present, many coal mine enterprises in our country have problems in tunneling support technology to varying degrees, which greatly increases the danger of coal mine tunneling construction. Therefore, in the coal mine excavation work, the corresponding excavation support technology should be adopted according to the actual situation of the mine, especially for the rectangular section support work of the mine, the appropriate support technology must be adopted. However, in the process of mine excavation, in order to blindly pursue progress, save capital investment and obtain greater economic benefits, simple support technology, such as I-steel shed support, is often adopted. However, if simple support technology is adopted in special geological structures such as faults and collapse columns, and if reinforcement measures are not taken in time to change the support technology, certain security risks will be buried.
1.3 low degree of mechanization
Although China's coal mining industry is large in scale, the mechanization level of coal mining in many enterprises is low, which not only cannot meet the production demand, but also has great security risks. At present, the widely used tunneling equipment in coal mines is cantilever roadheader, but the equipment still needs workers to operate underground, and the operation process is complicated. Therefore, Sino-Thai mining industry needs to continuously introduce high-level mechanized mining equipment.
1.4 Geological structure and complex construction conditions.
Great changes have taken place in the geological conditions of the existing driving roadways in the mine, especially the deep driving roadways are all cross-layer roadways, which are obviously affected by in-situ stress, leading to the cracking of the pulp skin at the back of the driving face in the mine rock roadway. At the same time, there are many faults in the roadway and the lithology of the roadway is changeable. Roof caving often occurs in the head-on roadway and roof of construction roadway.
2. Countermeasures to solve the problems existing in coal mining work
2. 1 Increase roadway section
With the continuous development of coal mining technology, the emerging new technologies have brought a lot of convenience to the coal industry, and the cross-sectional form of coal mine roadway has gradually evolved from trapezoid to arch, effectively improving the mining efficiency. From the point of view of use value, compared with other shapes, arch can greatly improve the utilization rate of roadway section. At present, Sino-Thai Mining has comprehensively increased the tunnel excavation section to ensure that the net section of the tunnel is above 14m2. The continuous popularization and application of large section in mines is more suitable for the construction conditions of large machinery, and large mechanization replaces manual labor, which greatly improves the work efficiency.
2.2 improve the coal mine excavation support technology
Coal mine excavation support technology is related to coal mining work and affects the development of coal mine industry to a certain extent. At present, China's coal mining enterprises are relatively backward in coal mine driving support technology, and it is impossible to implement the corresponding technology according to the specific conditions of the mine. Therefore, coal mining enterprises should improve the coal mine excavation support technology, and Zhongtai Mining Company chooses different excavation support technologies according to different geological conditions. For example, in general, the rectangular cross-section support needs the combined support of bolt and anchor cable. This support method is to insert the anchor rod into the borehole, then fix the anchor rod in the rock stratum, and use the anchor cable to move the rock stratum structure upward, thus improving the overall stability and safety of the rock stratum. For example, composite support is generally used for unstable roadways that have been repaired many times. This support technology has the characteristics of low cost, simple materials, easy assembly and simple technology, which can not only improve the bearing capacity of roadway, but also ensure the stability of surrounding rock, prolong the service life of roadway and ensure the safety of coal mining. For the roadway with short service life, under the condition of ensuring the strength of roadway support, anchor net support and shotcrete can be used to reduce the construction cost of roadway, speed up the construction progress of roadway and improve the level of single entry.
2.3 improve the degree of mechanization
Now all walks of life are advocating intelligence, and advanced technology is closely related to the mechanization of equipment, which also puts forward higher requirements for improving the mechanization level of China's coal industry. Only by further improving the mechanization degree of mining can the economic benefits of enterprises be well improved and they can occupy a place in the market competition. This needs to be improved from the aspects of mine environment investigation, machinery selection and use method. Therefore, mines should actively promote new processes and technologies, vigorously carry out technological innovation and scientific research, and do a good job in technological innovation to increase benefits. We will continue to implement scientific research projects such as the popularization and application of deep-hole blasting technology in rock roadway and the research on mechanized rapid excavation technology, strive to master the key technologies that affect current safety production, and encourage all kinds of small inventions to be changed. Actively promote the implementation of ZWY- 120-55L backhoe loader+DSJ100/63/2× 75 (SSJ1000/2× 75) belt conveyor+horizontal silo mechanized production line in the heading face of rock roadway to avoid all kinds of influences in transportation.
2.4 Strengthen the construction management during geological structure crossing.
During the period when the person in charge of construction is facing the geological structure, in order to ensure the safety of on-site construction, we have taken active and effective measures in the process of roadway excavation. First, reduce the cycle progress of small classes and change the construction technology of two excavations into one excavation to avoid large-scale roof caving; Second, after the roadway blasting, the roadway should be searched for roof and sprayed with temporary support slurry in time. Before the next blasting of roadway excavation, in addition to the bolting and shotcreting support, the anchor cable beam support must follow the corn-bread closely to ensure the construction safety; Thirdly, the blasting parameters should be modified in time according to the change of lithology, and more holes should be drilled around the roof or roadway side with poor lithology to control the charge. By taking effective measures, the site construction safety is ensured and the roof caving phenomenon of roadway is prevented. At the same time, the method of wall thickness grouting and anchor beam reinforcement is actively used to strengthen the roadway. After the roadway is strengthened by grouting and anchor beam, the supporting effect is obviously improved, and the roadway has no obvious damage in the past. This reinforcement measure effectively controls the deformation of the roadway, prolongs the service life of the roadway, and reduces the maintenance times and maintenance capital cost of the roadway.
Summary language
In a word, tunneling support is an important link in coal mining, which can provide guarantee for underground safety and construction efficiency. However, there are still many problems in the current tunnel support technology in China. Therefore, relevant coal mining enterprises should improve the tunneling support technology to solve these problems, constantly develop new technologies, and realize the mechanization of tunneling as soon as possible, so as to maintain the stability of coal mine surrounding rock strata and make the coal mine tunneling work safely and orderly.
refer to
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[2] Cao Jianbo, Li Jinxiang. Talking about the Problems and Countermeasures in Coal Mine Excavation Support [J]. Shandong Industrial Technology, 20 17, (05): 70.
[3] Chen Liming. Problems and Countermeasures of Coal Mine Excavation Support [J]. Science and Technology Innovation Herald, 20 17, 14 (07): 43-44.
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