Tunnel blasting auxiliary hole arrangement optimization method and device

Abstract

The application relates to the technical field of tunnel blasting, and discloses a tunnel blasting auxiliary hole arrangement optimization method and device, which aims to solve the problem that the existing auxiliary hole arrangement mode has an unsatisfactory blasting effect, and mainly comprises the following steps: determining a basic structure unit of an auxiliary hole netted hole arrangement structure; constructing a blasting simulation model of the basic structure unit through simulation software, and setting blasting parameters of the blasting simulation model according to actual working conditions; respectively performing blasting simulation on the blasting simulation model under different blast hole spacings to obtain a blasting effective stress nephogram and a blasting effect diagram corresponding to the different blast hole spacings; determining an optimal blast hole spacing according to the blasting effective stress nephogram and the blasting effect diagram, and optimizing the auxiliary hole netted hole arrangement structure according to the optimal blast hole spacing. The application can effectively utilize detonation energy, reduce the amount of explosives, minimize the influence of blasting on the surrounding environment, achieve an ideal blasting effect, and is suitable for tunnel blasting.

Description

Technical Field

[0001] This invention relates to the field of tunnel blasting technology, specifically to a method and apparatus for optimizing the layout of auxiliary holes in tunnel blasting. Background Technology

[0002] Tunnels are key and critical engineering projects in the construction of highways and railways. Tunnel blasting involves arranging a dense ring of blast holes along the tunnel excavation outline, using spaced and decoupled charging methods to minimize or prevent damage to the tunnel outline after blasting, resulting in minimal over- or under-excavation. During tunnel blasting construction, the blast holes on the excavation section are arranged in zones and detonated sequentially to gradually expand and complete one blasting excavation cycle. These zones are based on the location and function of the blast holes, and there are three types: cut holes, auxiliary holes, and peripheral holes. These three types of blast holes work together to complete one cycle of blasting excavation. Auxiliary holes are located between the cut holes and peripheral holes, and their function is to expand the cavity created by the cut holes, creating a free face for the peripheral holes. Typically, auxiliary holes are arranged in two ways: single-row (linear) and multi-row. Multi-row arrangements are further divided into square, triangular, and quincunx patterns. From the perspective of uniform energy distribution, an equilateral triangular arrangement is the most ideal and reasonable.

[0003] Because the tunnel is adjacent to existing buildings, the blasting site is surrounded by a dense population, residential buildings, and underground pipelines. To minimize the impact of blasting on the surrounding environment, it is necessary to control the amount of explosives used and optimize the layout of the blast holes. This ensures that the tunnel blasting effect achieves the goal of excavation while minimizing noise and disturbance. However, in current technology, the layout of auxiliary holes is usually determined by blasting personnel based on experience. This method places high demands on the blasting personnel and is highly subjective, easily leading to unsatisfactory blasting results. Summary of the Invention

[0004] The present invention aims to solve the problem that the existing auxiliary hole arrangement has unsatisfactory blasting effect, and proposes an optimized method and device for the arrangement of auxiliary holes in tunnel blasting.

[0005] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0006] On the one hand, a method for optimizing the layout of auxiliary blasting holes in tunnels is provided, the method comprising:

[0007] The basic structural unit of the auxiliary hole mesh structure is determined, and the auxiliary hole mesh structure can be obtained by repeated expansion of the basic structural unit.

[0008] A blasting simulation model of the basic structural unit is constructed using simulation software, and the blasting parameters of the blasting simulation model are set according to the actual working conditions.

[0009] Blasting simulations were performed based on the blasting simulation model at different borehole spacings to obtain effective stress cloud diagrams and blasting effect diagrams corresponding to different borehole spacings.

[0010] The optimal borehole spacing is determined based on the effective stress cloud diagram and blasting effect diagram, and the auxiliary hole mesh layout structure is optimized based on the optimal borehole spacing.

[0011] Furthermore, the basic structural unit is a rhombus composed of two equilateral triangles, with the four endpoints of the rhombus being the positions of the blast holes, and the distance between the blast holes being the side length of the rhombus.

[0012] Furthermore, the blasting parameters include: tunnel dimensions, explosive section thickness, overlying rock thickness, lower rock thickness, borehole diameter, and explosive charge diameter.

[0013] Furthermore, the simulation software is either ANSYS or DYNA.

[0014] On the other hand, a device for optimizing the arrangement of auxiliary holes in tunnel blasting is provided, the device comprising:

[0015] A determining unit is used to determine the basic structural unit of the auxiliary hole mesh structure, which can be obtained by repeated expansion of the basic structural unit;

[0016] The construction unit is used to construct the blasting simulation model of the basic structural unit through simulation software, and to set the blasting parameters of the blasting simulation model according to the actual working conditions.

[0017] The simulation unit is used to perform blasting simulation based on the blasting simulation model under different borehole spacings to obtain the effective stress cloud map and blasting effect map corresponding to different borehole spacings.

[0018] The optimization unit is used to determine the optimal borehole spacing based on the effective stress cloud diagram and blasting effect diagram, and to optimize the auxiliary hole mesh layout structure based on the optimal borehole spacing.

[0019] Furthermore, the basic structural unit is a rhombus composed of two equilateral triangles, with the four endpoints of the rhombus being the positions of the blast holes, and the distance between the blast holes being the side length of the rhombus.

[0020] Furthermore, the blasting parameters include: tunnel dimensions, explosive section thickness, overlying rock thickness, lower rock thickness, borehole diameter, and explosive charge diameter.

[0021] Furthermore, the simulation software is either ANSYS or DYNA.

[0022] The beneficial effects of this invention are as follows: The tunnel blasting auxiliary hole layout optimization method and device described in this invention analyzes the effective blasting stress and blasting effect of auxiliary holes under different hole spacing conditions through blasting simulation model, determines the optimal hole spacing of auxiliary holes, thereby enabling efficient blasting of the overall fractured surrounding rock of the tunnel, effectively utilizing detonation energy, reducing the amount of explosives used, minimizing the impact of blasting on the surrounding environment, and achieving ideal blasting effect, thus ensuring the construction cost, construction quality and construction safety of tunnel blasting. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating the tunnel blasting auxiliary hole layout optimization method according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the mesh-like hole area in the excavation section according to an embodiment of the present invention;

[0025] Figure 3 This is a simplified structural diagram of the auxiliary hole mesh structure described in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the basic structural unit described in an embodiment of the present invention;

[0027] Figure 5 This is a cloud diagram of the effective blasting stress when the borehole spacing is 70cm, as described in an embodiment of the present invention.

[0028] Figure 6 This is a diagram illustrating the blasting effect when the borehole spacing is 70cm, as described in an embodiment of the present invention.

[0029] Figure 7 This is a cloud diagram of the effective blasting stress when the borehole spacing is 80cm, as described in an embodiment of the present invention.

[0030] Figure 8 This is a diagram illustrating the blasting effect when the borehole spacing is 80cm, as described in an embodiment of the present invention.

[0031] Figure 9 This is a cloud diagram of the effective blasting stress when the borehole spacing is 90cm, as described in an embodiment of the present invention.

[0032] Figure 10 This is a diagram illustrating the blasting effect when the borehole spacing is 90cm, as described in an embodiment of the present invention.

[0033] Figure 11 This is a schematic diagram of the tunnel blasting auxiliary hole layout optimization device according to an embodiment of the present invention. Detailed Implementation

[0034] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0035] This invention aims to achieve efficient blasting of fractured surrounding rock in tunnels, effectively utilize detonation energy, reduce explosive usage, and minimize the impact of blasting on the surrounding environment to achieve ideal blasting results. It proposes a method and device for optimizing the layout of auxiliary holes in tunnel blasting. The main technical solutions include: determining the basic structural units of the auxiliary hole mesh layout, which can be repeatedly expanded to obtain the auxiliary hole mesh layout; constructing a blasting simulation model of the basic structural units using simulation software, and setting the blasting parameters of the simulation model according to actual working conditions; performing blasting simulations based on the simulation model at different borehole spacings to obtain effective stress cloud maps and blasting effect diagrams corresponding to different borehole spacings; determining the optimal borehole spacing based on the effective stress cloud maps and blasting effect diagrams, and optimizing the auxiliary hole mesh layout structure based on the optimal borehole spacing.

[0036] It is understandable that, due to the proximity of tunnel construction blasting to existing buildings, dense population, and numerous residential buildings and underground pipelines, the amount of explosives used in blasting needs to be controlled to minimize the impact on the surrounding environment. In this case, the amount of explosives per hole should be relatively small, and the hole layout should be relatively dense and uniform. While the layout of auxiliary holes in actual tunnel construction may appear complex, it is actually a repetition and expansion of the simplest and most basic structural units on a plane. Based on this, this invention uses the principle of symmetry and equivalence to simplify the hole layout into basic structural units. By studying the effective stress of these basic structural units, the effective stress of each basic unit within the mesh-like hole layout area of ​​the entire excavation section can be obtained. Specifically, after determining the basic structural units of the auxiliary hole mesh layout structure, a blasting simulation model of these basic structural units is constructed. Based on this blasting model, numerical simulations are performed on different hole spacings, and the blasting effects are compared and analyzed. This yields the optimal hole spacing for auxiliary holes in actual construction, allowing for optimization of the auxiliary hole mesh layout structure.

[0037] Example

[0038] Please see Figure 1 The tunnel blasting auxiliary hole layout optimization method according to the embodiments of the present invention includes the following steps:

[0039] Step 1: Determine the basic structural unit of the auxiliary hole mesh structure. The basic structural unit can be repeatedly expanded to obtain the auxiliary hole mesh structure.

[0040] Please see Figure 2Auxiliary holes are located between the cut holes and the peripheral holes. Their function is to expand the cavity created by the cut holes and create a free face for the blasting of the peripheral holes. Since tunnel construction blasting is near existing buildings, with a dense population, residential buildings, and underground pipelines, it is necessary to control the amount of explosives used in the blasting to minimize the impact of the blasting on the surrounding environment. In this case, the amount of explosives per hole should be relatively small, and the hole layout should be relatively dense and uniform. From the perspective of uniform distribution of blasting energy, an equilateral triangle hole layout is the most ideal and reasonable.

[0041] In actual working conditions, the layout of auxiliary boreholes in tunnels may appear intricate, but it is actually a repetition and expansion of the simplest and most basic equilateral triangular unit on a plane. Based on this, this embodiment uses the principle of symmetry equivalence to simplify the borehole layout. For the simplified borehole layout, please refer to [link / reference needed]. Figure 3 .

[0042] Figure 3 This is only a small part of the auxiliary porous mesh structure, while the entire massive porous mesh structure can... Figure 3 The portion shown is obtained by invalid repetition expansion, and each repeated portion is equivalent to a unit in the rhombic region ACEG. Therefore, the rhombic region ACEG can represent the entire planar mesh structure region. Figure 3 In the diagram, A, B, C, D, E, F, G, H, and K represent blast holes, respectively.

[0043] Please see Figure 3 The effective stress value at any point P within the region is mainly related to the boreholes B, K, and H at the three vertices of the equilateral triangle it contains. Other boreholes are too far apart to significantly affect the effective stress value. Furthermore, the lines connecting the boreholes in this region are equivalent. For example, line 1 is a diagonal in the rhomboid region ABKH, and line 2 is one of its sides. However, in the equivalent rhomboid region BCKH, line 2 is also a diagonal. Therefore, line 1 and line 2 are equivalent. In summary, the research object is further narrowed down to the X-direction in the rhomboid region ABKH, thus obtaining the basic structural unit of the auxiliary hole mesh structure.

[0044] Please see Figure 4 The rhomboid region ABKH is the basic structural unit that makes up the entire complex auxiliary hole mesh structure. The distance between the center points of boreholes B and H is the borehole spacing *a*, and the distance from borehole K to the line connecting BH is the row spacing *b*. From geometric relationships, it can be seen that... By studying the effective stress of rock mass units within the basic structural unit region, the effective stress of each unit within the entire planar mesh-like perforated region can be obtained.

[0045] Step 2: Construct a blasting simulation model of the basic structural unit using simulation software, and set the blasting parameters of the blasting simulation model according to the actual working conditions;

[0046] In this embodiment, ANSYS or DYNA software can be used to construct a blasting simulation model of basic structural units. The relevant blasting parameters include: tunnel dimensions, explosive section thickness, overlying rock thickness, lower rock thickness, borehole diameter, and charge diameter. In this embodiment, the tunnel dimensions are also taken as a 3.0m × 3.0m × 3.0m cube to simulate an infinitely homogeneous medium. The explosive section thickness is 1.4cm, and the overlying and lower rock thicknesses are both 8cm. The borehole diameter D is 4.2cm, and the charge diameter Φ is taken as 1.6cm based on the optimal decoupling coefficient Kd = 1.31. Blasting parameters may vary depending on actual working conditions; this embodiment does not impose any limitations on this.

[0047] Step 3: Perform blasting simulations based on the blasting simulation model under different borehole spacings to obtain the effective stress cloud diagram and blasting effect diagram corresponding to different borehole spacings;

[0048] It is understandable that by simultaneously setting different borehole spacings 'a', the blasting effects corresponding to different borehole spacings can be analyzed. The specific value of the borehole spacing 'a' can vary depending on the actual working conditions, and this embodiment does not impose any restrictions on it. This embodiment conducts blasting simulation analysis for three working conditions with borehole spacings 'a' of 70cm, 80cm, and 90cm.

[0049] When the borehole spacing a = 70 cm, the row spacing b = 60.62 cm, and the decoupling coefficient Kd = 1.31, please refer to the corresponding effective blasting stress cloud diagram. Figure 5 Please refer to the corresponding explosion effect diagram. Figure 6 .

[0050] from Figure 5 and Figure 6 It can be seen that the rock mass in the middle of the rhomboid area is a completely penetrated pulverized zone, and the rock mass around the blast hole has formed cracks. From the perspective of blasting effect, when the hole spacing is 70cm, the explosive damage to the surrounding rock mass is excessive and the explosive energy is not fully utilized.

[0051] When the borehole spacing a = 80cm, the row spacing b = 70cm, and the decoupling coefficient Kd = 1.31, please refer to the corresponding effective blasting stress cloud diagram. Figure 7 Please refer to the corresponding explosion effect diagram. Figure 8 .

[0052] from Figure 7 and Figure 8It can be seen that the effective stress of the four boreholes is completely superimposed, forming a whole area. The stress wave is transmitted to the four free surfaces. A through-type crack is formed in the middle and around the rhomboid area. From the perspective of blasting effect, the blasting effect of the explosive with a hole spacing of 80cm is more suitable for subsequent construction than that with a hole spacing of 70cm. It also effectively utilizes the detonation energy, reduces the amount of explosive used, and minimizes the impact of blasting on the surrounding environment.

[0053] When the borehole spacing a = 90cm, the row spacing b = 78cm, and the decoupling coefficient Kd = 1.31, please refer to the corresponding effective blasting stress cloud diagram. Figure 9 Please refer to the corresponding explosion effect diagram. Figure 10 .

[0054] from Figure 9 and Figure 10 It can be seen that the rock mass in the rhomboid area has cracks but has not formed a complete breakthrough. The rock mass around the blast hole has not been crushed. From the perspective of blasting effect, the explosive has not caused enough damage to the surrounding rock mass when the hole spacing is 90cm, and has failed to effectively create a free face for the blasting of the surrounding holes.

[0055] Step 4: Determine the optimal borehole spacing based on the effective stress cloud diagram and blasting effect diagram, and optimize the auxiliary hole mesh layout structure based on the optimal borehole spacing.

[0056] The simulation analysis above shows that by comparing the effective stress cloud diagram and blasting effect diagram under various borehole spacing conditions, and taking into full account the actual situation of the project, the need to minimize the disturbance and impact on the surrounding environment, and considering factors such as economic benefits and ease of construction, the optimal borehole spacing a = 80cm and row spacing b = 70cm rhomboid hole arrangement is determined as the best hole arrangement. Finally, the borehole spacing within the auxiliary hole mesh hole arrangement structure is set as the optimal borehole spacing, thus completing the optimization of the auxiliary hole mesh hole arrangement structure.

[0057] In summary, the tunnel blasting auxiliary hole layout optimization method described in this embodiment analyzes the effective blasting stress and blasting effect of auxiliary holes under different hole spacing conditions using a blasting simulation model, and determines the optimal hole spacing. This enables efficient blasting of the overall fractured surrounding rock of the tunnel, effectively utilizes detonation energy, reduces the amount of explosives used, minimizes the impact of blasting on the surrounding environment, and achieves ideal blasting results, ensuring the construction cost, construction quality, and construction safety of tunnel blasting.

[0058] Based on the above technical solution, this embodiment also proposes a device for optimizing the layout of auxiliary holes for tunnel blasting. Please refer to [link / reference]. Figure 11 The device includes:

[0059] A determining unit is used to determine the basic structural unit of the auxiliary hole mesh structure, which can be obtained by repeated expansion of the basic structural unit;

[0060] The construction unit is used to construct the blasting simulation model of the basic structural unit through simulation software, and to set the blasting parameters of the blasting simulation model according to the actual working conditions.

[0061] The simulation unit is used to perform blasting simulation based on the blasting simulation model under different borehole spacings to obtain the effective stress cloud map and blasting effect map corresponding to different borehole spacings.

[0062] The optimization unit is used to determine the optimal borehole spacing based on the effective stress cloud diagram and blasting effect diagram, and to optimize the auxiliary hole mesh layout structure based on the optimal borehole spacing.

[0063] It is understood that since the tunnel blasting auxiliary hole arrangement optimization device described in the embodiments of the present invention is a device for implementing the tunnel blasting auxiliary hole arrangement optimization method described in the embodiments, the device disclosed in the embodiments is relatively simple to describe because it corresponds to the method disclosed in the embodiments. For relevant parts, please refer to the description of the method.

Claims

1. A method for optimizing the layout of auxiliary blasting holes in tunnels, characterized in that, The method includes: The basic structural unit of the auxiliary hole mesh layout structure is determined. The basic structural unit can be obtained by repeated expansion. The basic structural unit is a rhombus composed of two equilateral triangles, the four endpoints of the rhombus are the positions of the blast holes, and the spacing between the blast holes is the side length of the rhombus. A blasting simulation model of the basic structural unit is constructed using simulation software, and the blasting parameters of the blasting simulation model are set according to the actual working conditions. Blasting simulations were performed based on the blasting simulation model at different borehole spacings to obtain effective stress cloud diagrams and blasting effect diagrams corresponding to different borehole spacings. The optimal borehole spacing is determined based on the effective stress cloud diagram and blasting effect diagram, and the auxiliary hole mesh layout structure is optimized based on the optimal borehole spacing.

2. The method for optimizing the layout of tunnel blasting auxiliary holes as described in claim 1, characterized in that, The blasting parameters include: tunnel dimensions, explosive section thickness, overlying rock thickness, lower rock thickness, borehole diameter, and explosive charge diameter.

3. The method for optimizing the layout of tunnel blasting auxiliary holes as described in claim 1, characterized in that, The simulation software is either ANSYS or DYNA.

4. A device for optimizing the layout of auxiliary holes for tunnel blasting, characterized in that, The device includes: A determining unit is used to determine the basic structural unit of the auxiliary hole mesh layout structure. The basic structural unit can be obtained by repeated expansion of the auxiliary hole mesh layout structure. The basic structural unit is a rhombus composed of two equilateral triangles, the four endpoints of the rhombus are the positions of the blast holes, and the spacing between the blast holes is the side length of the rhombus. The building unit is used to build a blasting simulation model of the basic structural unit through simulation software, and to set the blasting parameters of the blasting simulation model according to the actual working conditions. The simulation unit is used to perform blasting simulation based on the blasting simulation model under different borehole spacings to obtain the effective stress cloud map and blasting effect map corresponding to different borehole spacings. The optimization unit is used to determine the optimal borehole spacing based on the effective stress cloud diagram and blasting effect diagram, and to optimize the auxiliary hole mesh layout structure based on the optimal borehole spacing.

5. The tunnel blasting auxiliary hole layout optimization device as described in claim 4, characterized in that, The blasting parameters include: tunnel dimensions, explosive section thickness, overlying rock thickness, lower rock thickness, borehole diameter, and explosive charge diameter.

6. The tunnel blasting auxiliary hole layout optimization device as described in claim 4, characterized in that, The simulation software is either ANSYS or DYNA.

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