A support method for mining area and tunnel in abnormal area of ​​mine

Abstract

The present invention discloses a method for supporting a stope and a tunnel in an abnormal area of ​​a mine. Based on the RMR and Q classification systems, support schemes and parameters for the tunnels in the upper wall surrounding rock, ore body and lower wall surrounding rock of abnormal areas III and IV are designed respectively. It is recommended that all tunnels in the entire mining area be supported. The recommended support scheme is: anchor rod + metal mesh + top plate shotcrete; the parameters are: anchor rod length 2.2m, anchor rod mesh 1.5m×1.5m; for areas such as broken zones, weak rock formations and tunnel intersections, it is necessary to appropriately increase the support strength or use long anchor cables according to the on-site conditions. The present application has the advantages of more stable stope and tunnel support methods, improved mining safety, etc.

Description

Technical Field

[0001] The invention relates to the technical field of ore dressing, and in particular to a method for supporting a stope and a tunnel in an abnormal area of ​​a mine. Background Art

[0002] The Secretary Gou Iron Mine is located in Zhangerkouzi Village, two kilometers west of Xiaoshetai Town, Urad Front Banner, Bayannur City, Inner Mongolia Autonomous Region. The geographical coordinates of the center of the mining area are: longitude: 109°28′30″, latitude: 41°09′46″; the iron ore body in the mining area is located in the gneiss section of the Sertengshan Group, and the main lithology is plagioclase amphibolite gneiss and mixed rock plagioclase. The mining area is divided into Ⅰ, Ⅱ, Ⅲ,

[0003] There are four abnormal areas in No. Ⅳ, among which the mining of ore bodies in abnormal areas Ⅰ and Ⅱ share a production system, numbered as mining area 1; the mining of ore bodies in abnormal areas Ⅲ and Ⅳ share a production system, numbered as mining area 2. The production systems of mining areas 1 and 2 are relatively independent and are both being mined. The elevation of the ore body ranges from 1360m to 780m. The ore bodies in abnormal areas Ⅲ and Ⅳ are nearly east-west, with a total length of about 1270m from east to west and a width of about 530m from north to south; the second mining area is mainly thick ore bodies, with a small proportion of medium-thick and thin ore bodies, which are steeply inclined ore bodies; the mine design determines that the thick ore body (thickness>15m) adopts the segmented rock drilling and segmented empty field mining method vertical to the ore body trend, and the medium-thick ore body (thickness<15m) adopts the segmented rock drilling and segmented empty field mining method along the ore body trend and subsequent filling mining method.

[0004] At present, the main support methods used for the roof and tunnels of the mines in the abnormal areas III and IV are pipe anchor rods + metal mesh + shotcrete. The support means are single, there is a lack of basis for determining the support parameters, and there is a lack of corresponding support technical standards, which often leads to the instability of the mine support structure. Through on-site investigation, it is known that some mines have the problem of roof support failure during the period of ore landing and mining, resulting in large-scale collapse of the mine roof, and the collapse height even reaches more than 50m, causing the upper and middle sections to collapse, and the adjacent mine rooms cannot be mined, resulting in large ore losses and poor operation safety. In addition, through actual on-site investigation, there are a large number of large blocks with a thickness greater than 2.2m that have fallen, indicating that the pipe anchor rods used in the mine cannot effectively control the ground pressure. It is urgent to optimize the current support methods of the mine and formulate corresponding support technical standards. Summary of the invention

[0005] The invention discloses a method for supporting a stope and a tunnel in an abnormal area of ​​a mine, so as to solve the defects of the prior art mentioned in the background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for supporting a stope and a tunnel in an abnormal area of ​​a mine, comprising the following steps:

[0007] (1) Conduct on-site engineering geological surveys of the mining areas and tunnels: Conduct rock mass structural surface information surveys and core surveys at 1200m, 1140m, 1120m, 1080m, and 1030m in abnormal mining areas III and IV, and analyze the investigated joints using DIPS5.1 software;

[0008] (2) Rock mechanics test: The physical and mechanical properties of the surrounding rocks and ore bodies in the upper and lower plates of the anomaly areas III and IV were tested and analyzed. The rock samples used in the test were chlorite schist blocks and magnetite quartz blocks collected from the anomaly areas III and IV of Dazhong Mining. The rock blocks had no obvious joints and cracks and had good integrity. The samples were subjected to uniaxial compression tests, Brazilian splitting tests, and shear tests using a hydraulic universal testing machine.

[0009] (3) Estimation of geostress in abnormal areas III and IV: Based on the measured vertical stress data, a scatter plot of the vertical stress and horizontal stress distribution with depth is made and estimated;

[0010] (4) Rock mass quality classification of abnormal areas III and IV: Based on the results of engineering geological survey and rock mechanics tests, the rock mass quality (Q) classification evaluation method of Barton rock mass, rock mass geomechanical classification index value (RMR), and geological strength index (GSI) are used to classify the rock mass quality of abnormal areas III and IV.

[0011] (5) Estimation of rock mass mechanical parameters in abnormal areas III and IV: Based on the classification of engineering rock mass, empirical relationships are established to determine rock mass mechanical parameters, and rock mass mechanical characteristic indicators close to the actual ones are obtained for engineering rock mass calculations;

[0012] (6) Analysis and control of rock mass stability in abnormal areas III and IV: measurement of tunnel dimensions, tunnel stability time analysis based on RMR, tunnel stability analysis based on Unwedge, numerical simulation analysis of tunnel stability, and analysis of factors affecting tunnel stability;

[0013] (7) Design method of tunnel support in abnormal areas III and IV:

[0014] ① The tunnel in the surrounding rock of the abnormal hanging wall in the abnormal area Ⅲ: the tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.4m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0015] ②Tunnel inside the abnormal ore body in the abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 2.0m. The roof is supported by metal mesh and the roof is sprayed with 50mm thick concrete;

[0016] ③Tunnel in the surrounding rock of abnormal footwall in abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.5m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0017] ④IV Tunnel in the surrounding rock of abnormal hanging wall: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.5m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0018] ⑤IV Tunnel inside abnormal ore body: Tunnel roof support adopts 2.2m long anchor rods with an anchor rod spacing of 2.0m, the roof is supported by metal mesh, and the roof is sprayed with 50mm thick concrete;

[0019] ⑥Ⅳ Tunnel in the abnormal footwall surrounding rock: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.8m. The roof is supported by metal mesh and 50mm thick concrete is sprayed on the roof.

[0020] The beneficial effects of adopting the above technical solution are:

[0021] This application estimates the rock strength in the mine and tunnels through field surveys and data analysis, and combines anchor rods, metal mesh and concrete to increase support strength and improve support safety. DETAILED DESCRIPTION

[0022] Embodiments of the present invention are described in detail below:

[0023] A method for supporting a mine stope and a tunnel in an abnormal area of ​​a mine, comprising the following steps:

[0024] (1) Conduct on-site engineering geological surveys of the mining areas and tunnels: Conduct rock mass structural surface information surveys and core surveys at 1200m, 1140m, 1120m, 1080m, and 1030m in abnormal mining areas III and IV, and analyze the investigated joints using DIPS5.1 software;

[0025] (2) Rock mechanics test: The physical and mechanical properties of the surrounding rocks and ore bodies in the upper and lower plates of the anomaly areas III and IV were tested and analyzed. The rock samples used in the test were chlorite schist blocks and magnetite quartz blocks collected from the anomaly areas III and IV of Dazhong Mining. The rock blocks had no obvious joints and cracks and had good integrity. The samples were subjected to uniaxial compression tests, Brazilian splitting tests, and shear tests using a hydraulic universal testing machine.

[0026] (3) Estimation of geostress in abnormal areas III and IV: Based on the measured vertical stress data, a scatter plot of the vertical stress and horizontal stress distribution with depth is made and estimated;

[0027] (4) Rock mass quality classification of abnormal areas III and IV: Based on the results of engineering geological survey and rock mechanics tests, the rock mass quality (Q) classification evaluation method of Barton rock mass, rock mass geomechanical classification index value (RMR), and geological strength index (GSI) are used to classify the rock mass quality of abnormal areas III and IV.

[0028] (5) Estimation of rock mass mechanical parameters in abnormal areas III and IV: Based on the classification of engineering rock mass, empirical relationships are established to determine rock mass mechanical parameters, and rock mass mechanical characteristic indicators close to the actual ones are obtained for engineering rock mass calculations;

[0029] (6) Analysis and control of rock mass stability in abnormal areas III and IV: measurement of tunnel dimensions, tunnel stability time analysis based on RMR, tunnel stability analysis based on Unwedge, numerical simulation analysis of tunnel stability, and analysis of factors affecting tunnel stability;

[0030] (7) Design method of tunnel support in abnormal areas III and IV:

[0031] ① The tunnel in the surrounding rock of the abnormal hanging wall in the abnormal area Ⅲ: the tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.4m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0032] ②Tunnel inside the abnormal ore body in the abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 2.0m. The roof is supported by metal mesh and the roof is sprayed with 50mm thick concrete;

[0033] ③Tunnel in the surrounding rock of abnormal footwall in abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.5m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0034] ④IV Tunnel in the surrounding rock of the abnormal hanging wall: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.5m. The roof is supported by metal mesh. The top plate is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete.

[0035] ⑤IV Tunnel inside abnormal ore body: Tunnel roof support adopts 2.2m long anchor rods with an anchor rod spacing of 2.0m, the roof is supported by metal mesh, and the roof is sprayed with 50mm thick concrete;

[0036] ⑥Ⅳ Tunnel in the abnormal footwall surrounding rock: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.8m. The roof is supported by metal mesh and 50mm thick concrete is sprayed on the roof.

[0037] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for supporting the stope and tunnel in an abnormal area of ​​a mine, characterized in that: The following steps are included (1) Conduct on-site engineering geological surveys of the mining areas and tunnels: Conduct rock mass structural surface information surveys and core surveys at 1200m, 1140m, 1120m, 1080m, and 1030m in abnormal mining areas III and IV, and analyze the investigated joints using DIPS5.1 software; (2) Rock mechanics test: The physical and mechanical properties of the surrounding rocks and ore bodies in the upper and lower plates of the anomaly areas III and IV were tested and analyzed. The rock samples used in the test were chlorite schist blocks and magnetite quartz blocks collected from the anomaly areas III and IV of Dazhong Mining. The rock blocks had no obvious joints and cracks and had good integrity. The samples were subjected to uniaxial compression tests, Brazilian splitting tests, and shear tests using a hydraulic universal testing machine. (3) Estimation of geostress in abnormal areas III and IV: Based on the measured vertical stress data, a scatter plot of the vertical stress and horizontal stress distribution with depth is made and estimated; (4) Rock mass quality classification of abnormal areas III and IV: Based on the results of engineering geological survey and rock mechanics tests, the rock mass quality (Q) classification evaluation method of Barton rock mass, rock mass geomechanical classification index value (RMR), and geological strength index (GSI) are used to classify the rock mass quality of abnormal areas III and IV. (5) Estimation of rock mass mechanical parameters in abnormal areas III and IV: Based on the classification of engineering rock mass, empirical relationships are established to determine rock mass mechanical parameters, and rock mass mechanical characteristic indicators close to the actual ones are obtained for engineering rock mass calculations; (6) Analysis and control of rock mass stability in abnormal areas III and IV: measurement of tunnel dimensions, tunnel stability time analysis based on RMR, tunnel stability analysis based on Unwedge, numerical simulation analysis of tunnel stability, and analysis of factors affecting tunnel stability; (7) Design method of tunnel support in abnormal areas III and IV: ① The tunnel in the surrounding rock of the abnormal hanging wall in the abnormal area Ⅲ: the tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.4m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete. ②Tunnel inside the abnormal ore body in the abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 2.0m. The roof is supported by metal mesh and the roof is sprayed with 50mm thick concrete; ③Tunnel in the surrounding rock of abnormal footwall in abnormal area III: The tunnel roof is supported by 2.2m long anchor rods with an anchor rod spacing of 1.5m. The roof is supported by metal mesh. The roof is sprayed with 50-100mm thick concrete, and the two sides are sprayed with 30mm thick concrete. ④IV Tunnel in the surrounding rock of abnormal hanging wall: The tunnel roof support adopts 2.2m long anchor rods with a spacing of 2.2m. 1.5m, the top plate is supported by metal mesh, the top plate is sprayed with 50-100mm thick concrete, and the two sides are sprayed 30mm thick concrete; ⑤Ⅳ abnormal ore body tunnel: the tunnel roof support adopts 2.2m long anchor rods with an anchor rod spacing of 2.0m. The top plate is supported by metal mesh and sprayed with 50mm thick concrete; ⑥IV Tunnel in the surrounding rock of abnormal footwall: The tunnel roof support adopts 2.2m long anchor rods with a spacing of 2.2m. 1.8m, the top plate is supported by metal mesh and the top plate is sprayed with 50mm thick concrete.