A tunnel construction method using laser rock breaking

Abstract

The present invention provides a tunnel construction method using laser rock breaking, comprising: step S110: using laser to cut the tunnel face along a preset trajectory, so that the tunnel face forms a concave-convex rock mass with a cut to be squeezed; step S120: using an extrusion device to squeeze the concave-convex rock mass from the cut to be squeezed, so that the concave-convex rock mass breaks and falls off; step S130: repeating steps S110 to S120 until a preset excavation depth is reached. The present invention uses laser to replace the tool, and the laser destroys the rock in the form of thermal fragmentation, melting and gasification, so that a concave-convex rock mass is formed on the tunnel face, and the integrity and connection strength of the tunnel face are greatly reduced, and then the extrusion device is used to squeeze the concave-convex rock mass to break and fall off. The present invention abandons the traditional metal tool rock breaking method, fundamentally solves the problem that the metal tool of the tunnel boring machine is very prone to abnormal damage when cutting rock, improves construction efficiency, and saves high tool costs.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel excavation, in particular to a tunnel construction method using laser rock breaking. Background Art

[0002] With the development of underground space development projects such as water conservancy and hydropower projects, subways and tunnel projects, tunnel excavation methods and construction equipment have been continuously improved, but still have certain limitations.

[0003] The traditional drilling and blasting method is applicable to a wide range of geological conditions, but the construction efficiency is slow, the construction workers have high workload, the working environment is harsh, causing serious environmental pollution, and the construction process is noisy, so it is not suitable for the construction of urban subways.

[0004] Shield construction, TBM construction and cantilever tunneling machine construction are all tunnel construction methods developed in recent years. Metal cutters (rollers, scrapers, picks, etc.) are generally used for rock breaking. For rock formations of general strength (within 100Mpa), the rock breaking efficiency is acceptable. However, when encountering isolated rocks and harder rocks during excavation, the rock breaking efficiency will decrease, and the cutter will wear abnormally and the replacement frequency will increase, which will lead to a decrease in shield excavation efficiency and an increase in excavation costs. At the same time, when excavating severely uneven geology such as soft on top and hard on the bottom, or uneven softness and hardness, traditional metal cutters are prone to abnormal damage.

[0005] Traditional shield construction methods have low flexibility in adapting to tunnel cross-sectional shapes, and the utilization rate of excavated tunnels is low, resulting in serious waste of resources. In addition, traditional shield manufacturing costs are high, which significantly increases tunnel construction costs. Summary of the invention

[0006] The purpose of the present invention is to provide a tunnel construction method using laser rock breaking to solve the problems of low construction efficiency, abnormal wear of cutters and increased replacement frequency in existing tunnel construction methods.

[0007] To achieve the above-mentioned purpose, the present invention proposes a tunnel construction method using laser rock breaking, comprising: step S110: using laser to cut the tunnel face along a preset trajectory, so that the tunnel face forms a concave-convex rock mass with a cut to be squeezed; step S120: using an extrusion device to squeeze the concave-convex rock mass from the cut to be squeezed, so that the concave-convex rock mass is broken and falls off; step S130: repeating steps S110 to S120 until a preset excavation depth is reached.

[0008] In the tunnel construction method using laser rock breaking as described above, in step S110, a plurality of parallel laser emitting devices are used to collaboratively emit lasers to the tunnel face, so as to perform parallel collaborative cutting on the tunnel face along cross tracks or parallel tracks.

[0009] The tunnel construction method of laser rock breaking as described above, wherein, further includes: step S101: designing the tunnel cross-sectional profile to obtain a tunnel cross-sectional profile design drawing; step S102: designing the laser scanning range and the arrangement of the extrusion device according to the tunnel cross-sectional profile design drawing; step S103: excavating the tunnel cross-sectional profile according to the tunnel cross-sectional profile design drawing.

[0010] The tunnel construction method of laser rock breaking as described above, wherein, further includes: step S104: scanning the tunnel cross-sectional contour to obtain a tunnel cross-sectional contour image; step S105: comparing the tunnel cross-sectional contour image with the tunnel cross-sectional contour design drawing, if the shapes of the two are inconsistent, trimming the tunnel cross-sectional contour until the tunnel cross-sectional contour is consistent with the shape of the tunnel cross-sectional contour design drawing.

[0011] In the tunnel construction method using laser rock breaking as described above, in step S104, a scanning device is used to scan the tunnel cross-sectional profile; in step S105, a host computer is used to form a three-dimensional model of the tunnel cross-sectional profile, and the three-dimensional model is compared with the tunnel cross-sectional profile design drawing.

[0012] In the tunnel construction method using laser rock breaking as described above, in step S103, a free-face tunnel boring machine or a full-face tunnel boring machine is used to excavate the tunnel section profile.

[0013] In the tunnel construction method using laser rock breaking as described above, in the step S110, a laser installed on a free-face tunnel boring machine or a full-face tunnel boring machine is used to emit laser, and the laser is formed by connecting a plurality of laser generating units in parallel.

[0014] In the tunnel construction method of laser rock breaking as described above, in the step S120, a plurality of squeezing devices installed on a free-face tunnel boring machine or a full-face tunnel boring machine are used to extrude the concave-convex rock mass, and the arrangement positions of the plurality of squeezing devices correspond to the positions of the incisions to be squeezed.

[0015] In the tunnel construction method using laser rock breaking as described above, in the step S120, the squeezing device is a wedge-shaped squeezing device.

[0016] In the tunnel construction method using laser rock breaking as described above, in step S110, the laser power, laser light source shape, laser target distance, laser scanning angle and laser cutting speed are set according to the geological conditions.

[0017] The characteristics and advantages of the laser rock breaking tunnel construction method of the present invention are:

[0018] 1. The present invention uses laser to replace the tool. The laser destroys the rock by thermal fragmentation, melting and gasification, so that a concave-convex rock mass with an incision to be squeezed is formed on the tunnel face, and the integrity and connection strength of the tunnel face are greatly reduced. Then, an extrusion device is used to squeeze the concave-convex rock mass from the incision to be squeezed, so that the concave-convex rock mass is broken and falls off, achieving the effect of tunnel excavation. The present invention abandons the traditional rock breaking method of metal tools, fundamentally solves the problem that the metal tools of the tunnel boring machine are prone to abnormal damage when cutting rocks, improves construction efficiency, and saves high tool costs;

[0019] 2. The present invention designs the tunnel cross-sectional profile before construction, and designs the laser scanning range and the arrangement of the extrusion device according to the tunnel cross-sectional profile design drawing, so that the laser can act on the tunnel face accurately and the extrusion device can crush the concave and convex rock mass accurately, thereby improving the construction accuracy and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following drawings are intended only to illustrate and explain the present invention, and do not limit the scope of the present invention.

[0021] Figure 1 is a flow chart of a tunnel construction method using laser rock breaking according to an embodiment of the present invention;

[0022] Figure 2 It is a flow chart of a tunnel construction method using laser rock breaking according to another embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described with reference to the accompanying drawings.

[0024] like Figure 1 As shown, the present invention provides a tunnel construction method using laser rock breaking, comprising the following steps:

[0025] Step S110: using laser to cut the tunnel face along a preset trajectory, so that the tunnel face forms a concave-convex rock mass with a cut to be squeezed;

[0026] Step S120: using an extrusion device to squeeze the concavo-convex rock mass from the incision to be squeezed, so that the concavo-convex rock mass is broken and falls off;

[0027] Step S130: Repeat steps S110 to S120 until a preset excavation depth is reached.

[0028] The present invention adopts laser to replace the tool. The laser destroys the rock by means of thermal fragmentation, melting and gasification, so that a concave-convex rock mass with an incision to be extruded is formed on the face of the tunnel, that is, the face of the tunnel becomes an incomplete free-air face, and the integrity and connection strength of the face of the tunnel are greatly reduced. Then, an extrusion device is used to extrude the concave-convex rock mass to break it and fall off, thereby achieving the effect of tunnel excavation. The present invention abandons the traditional method of breaking rock with metal tools, and fundamentally solves the problem that the metal tools of the tunnel boring machine are very likely to be damaged abnormally when cutting rock, thereby improving construction efficiency and saving high tool costs.

[0029] The laser rock breaking adopted by the present invention has the following principle:

[0030] Compared with ordinary light sources, lasers have the characteristics of high brightness, high directivity, and high monochromaticity. Rocks are composed of a variety of mineral particles. When lasers are irradiated on the surface of rocks, these mineral particles show differences in thermal expansion anisotropy and thermal expansion inhomogeneity due to the different thermal conductivity coefficients of each phase change boundary. Laser irradiation time and laser power are the main factors that determine whether laser rock breaking can be successful. The greater the laser power, the faster the laser rock breaking speed and the deeper the cutting depth on the rock.

[0031] Laser rock breaking basically destroys rocks by thermal fragmentation, melting and gasification. When the laser acts on the rock surface, but the heat generated is close to but does not reach the latent heat of liquefaction of the rock, thermal fragmentation will occur, resulting in a large number of cracks or loose rock flakes; when the heat generated reaches or exceeds the latent heat of liquefaction of the rock, the rock directly melts into liquid; when the heat reaches or exceeds the latent heat of vaporization of the rock, the rock directly gasifies from solid to gas. In the process of laser rock breaking, the rock in the laser spot area and the surrounding rock matrix will undergo a sudden change of solid, liquid and gas phases, during which there is a very complex three-dimensional unstable heat energy transfer and exchange.

[0032] In one embodiment, in step S110, multiple parallel laser emitting devices are used to collaboratively emit lasers to the tunnel face, so as to perform parallel collaborative cutting on the tunnel face along cross tracks or parallel tracks. "Parallel" means that the multiple laser emitting devices can work independently of each other, and "collaborative" means that the multiple laser emitting devices work in coordination to emit lasers for cutting the tunnel face along cross tracks or parallel tracks.

[0033] When multiple laser emitting devices emit lasers to cut the tunnel face along cross-trajectories, the shape of the cuts to be squeezed is a cross-penetrating shape, such as a grid shape. The cross-penetrating cuts divide the tunnel face into multiple independent rock blocks, which can be easily crushed and fallen off by the squeezing device.

[0034] When multiple laser emitting devices emit lasers to cut the tunnel face along parallel trajectories, the shape of the cuts to be extruded can be multiple parallel long strip cuts. The multiple long strip cuts divide the tunnel face into multiple independent convex ridge-shaped rock strips. The shape of each cut can be straight or curved, or circular. The shape of each rock strip can be straight or curved, or circular. The rock strips are also easier to be crushed and fall off by the extrusion device.

[0035] like Figure 2 As shown, in one embodiment, the tunnel construction method of the present invention further includes the following steps:

[0036] Step S101: designing a tunnel cross-section profile to obtain a tunnel cross-section profile design drawing;

[0037] Step S102: designing the laser scanning range and the arrangement of the extrusion device according to the tunnel section profile design drawing;

[0038] Step S103: excavating the tunnel cross-section profile according to the tunnel cross-section profile design drawing.

[0039] The laser scanning range is designed so that the laser scanning range is within the tunnel section contour, so that the overall contour shape of the cut made by the laser on the tunnel face is consistent with the shape of the tunnel section contour. For example, the shape of the tunnel section contour is designed to be circular, elliptical or square, and of course it can also be other shapes.

[0040] This embodiment improves construction accuracy and efficiency by designing the tunnel section profile, performing construction according to the design drawing, and designing the laser scanning range.

[0041] like Figure 2 As shown, further, the tunnel construction method of the present invention also includes the following steps:

[0042] Step S104: Scanning the tunnel cross-section profile to obtain a tunnel cross-section profile image; for example, using a scanning device to scan the tunnel cross-section profile;

[0043] Step S105: Compare the tunnel cross-sectional contour image with the tunnel cross-sectional contour design drawing. If the shapes of the two are inconsistent, the tunnel cross-sectional contour is trimmed until the tunnel cross-sectional contour is consistent with the shape of the tunnel cross-sectional contour design drawing; for example, a host computer is used to form a three-dimensional model of the tunnel cross-sectional contour through point cloud computing and image processing, and the host computer is used to compare and calculate the three-dimensional model with the tunnel cross-sectional contour design drawing. If the shapes of the two are consistent, the next step of construction is carried out; if the shapes of the two are inconsistent, the tunnel cross-sectional contour is trimmed until the shapes of the two are consistent.

[0044] In step S150, specifically, each time the tunnel cross-section profile is trimmed, step S104 is executed once to determine whether the trimmed tunnel cross-section profile is consistent with the shape of the tunnel cross-section profile design drawing based on the tunnel cross-section profile image obtained by scanning.

[0045] This embodiment can further improve the construction accuracy by scanning the tunnel cross-section profile, comparing and calculating the tunnel cross-section profile with the design drawing, and trimming the tunnel cross-section profile according to the comparison result.

[0046] In a specific embodiment, in step S103, a free-face tunnel boring machine or a full-face tunnel boring machine is used to excavate the tunnel section profile, and a breaker hammer may be used to assist.

[0047] In a specific embodiment, in step S110, multiple lasers installed on a free-face tunnel boring machine or a full-face tunnel boring machine are used to emit lasers. The lasers are formed by multiple laser generating units connected in parallel, so each laser generating unit is independent of each other and can be turned on or off separately. During construction, different numbers of laser generating units are turned on or off according to different stratum conditions to generate lasers of different powers to avoid energy waste. If a laser generating unit is damaged, it can be replaced separately, reducing the repair and maintenance costs of the equipment.

[0048] The laser's transmitting head can be replaced according to the formation conditions to generate point laser or line laser.

[0049] In a specific embodiment, in step S120, a plurality of squeezing devices installed on a free-face tunnel boring machine or a full-face tunnel boring machine are used to extrude the concave-convex rock mass, and the arrangement positions of the plurality of squeezing devices correspond to the positions of the incisions to be squeezed, so as to squeeze from the free surface of the incisions to be squeezed, so that the concave-convex rock mass is broken from the root, thereby peeling the rock blocks from the tunnel face.

[0050] For example, the extrusion device is driven by a linear drive device such as a telescopic cylinder, that is, the linear drive device drives the extrusion device to move linearly along the depth direction of the incision to be extruded to extrude the concave-convex rock mass. The extrusion device has simple operation and good extrusion effect.

[0051] The extrusion device has an extrusion thickness greater than the width of the cut to be extruded, so as to achieve the extrusion purpose.

[0052] For example, the extrusion device is a wedge-shaped extrusion device, specifically, the wedge-shaped extrusion device is a wedge-shaped block, whose thickness gradually decreases from the rear end to the front end (the end close to the incision to be extruded), and the front end of the wedge block is first inserted into the incision to be extruded. As the insertion depth of the wedge block increases, the thicker part of the wedge block exerts greater and greater extrusion pressure on the rock mass, thereby squeezing the rock mass and breaking it.

[0053] In one embodiment, in step S110, the laser power, laser light source shape, laser target distance, laser scanning angle and laser cutting speed are set according to the geological conditions. The greater the laser power, the faster the laser breaks the rock, and the deeper the laser cuts the rock. Therefore, for harder rock, a larger laser power can be set; the laser light source shape can be a point light source or a line light source, which can be set according to actual needs; the laser target distance is usually set to 50mm to 100mm, the laser scanning angle is usually set to plus or minus -30° to +30°, and the laser cutting speed is usually set to less than 5m / min. Of course, these parameters can be adjusted according to actual needs.

[0054] like Figure 2 As shown, in one embodiment, the tunnel construction method of the present invention further includes the following steps:

[0055] Step S140: transporting the fallen rock mass to the outside of the tunnel, for example, using a bouldering machine in conjunction with a slag truck to transport the fallen rock mass to the outside of the tunnel;

[0056] Step S150: lining the excavated tunnel.

[0057] In this embodiment, step S140 and step S150 can be executed after step S130 is completed, or can be executed during the execution of step S120, that is, the broken rock mass is transported out of the tunnel in real time to prevent the rock mass from accumulating in the tunnel and affecting the construction. The tunnel lining can also be constructed once after each tunnel excavation is completed to ensure the structural stability of the excavated tunnel section.

[0058] The present invention utilizes the crushing, melting and evaporation effects of laser on rocks to generate incisions to be extruded on the tunnel face that are the same as the laser scanning trajectory, and utilizes multiple lasers to cooperate with each other to make the generated incisions to be extruded in a cross or parallel shape, so that the complete tunnel face forms a concave-convex rock structure with many free surfaces, and the integrity and connection strength of the tunnel face are greatly reduced. Then, an extrusion device is used to extrude the generated incisions, so that the concave-convex rock structure is broken from the root, and then peeled off from the tunnel face to become large blocks of rock slag, which are finally transported out by a bouldering machine and a slag transporter.

[0059] Compared with the prior art, the present invention has at least the following advantages:

[0060] 1. The present invention uses lasers and extrusion devices to break rocks and achieve the purpose of tunnel excavation. It abandons the traditional way of breaking rocks with metal cutters of tunnel boring machines, fundamentally solves the problem that the metal cutters of tunnel boring machines are prone to abnormal damage when cutting rocks, and saves up to millions of tool costs;

[0061] 2. The present invention uses a laser to cut the tunnel face. Before the operation, the installation position, scanning trajectory and angle of the laser can be designed according to the tunnel section profile design drawing, so that the laser can accurately act on the tunnel face and the generated incision boundary is clear, which reduces the occurrence of over-excavation and under-excavation during tunnel excavation, reduces the construction workload of construction workers on the secondary treatment of the tunnel wall, reduces the construction difficulty during the grouting and secondary lining process, and thus reduces the construction cost;

[0062] 3. The present invention can freely design the size, installation position and scanning trajectory of the laser and the extrusion device according to the tunnel section profile design drawing, so as to control the laser cutting trajectory to coincide with the tunnel section profile, improve the utilization rate of tunnel excavation, and reduce unnecessary energy waste;

[0063] 4. The present invention can use free-section tunneling equipment or full-section tunneling equipment. Since no cutter is used, there is no need for a central main drive to drive the cutter head to rotate to complete the rock breaking action. Therefore, the traditional driving method of multiple sets of motors or hydraulic motor reducers around can be abandoned. Only a low-power guide rail drive motor is needed to drive the laser transmitter head to sweep, and a drive cylinder equipped with an extrusion device can complete tunneling, which saves the manufacturing cost of the tunneling machine to a great extent and leaves more layout space at the rear of the cutter head.

[0064] 5. The slag produced by the method of the present invention is generally a regular large rock block, which can be used as a raw material for stone for secondary processing, which not only avoids waste of resources but also generates income for the construction unit.

[0065] The above description is only an illustrative specific implementation mode of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any technician in the field without departing from the concept and principle of the present invention should fall within the scope of protection of the present invention. It should also be noted that the various components of the present invention are not limited to the above-mentioned overall application. The various technical features described in the specification of the present invention can be selected one by one or multiple ones can be selected and used in combination according to actual needs. Therefore, the present invention naturally covers other combinations and specific applications related to the invention point of this case.

Claims

1. A tunnel construction method using laser rock breaking, characterized in that: include: Step S110: using laser to cut the tunnel face along a preset trajectory, so that the tunnel face forms a concave-convex rock mass with a cut to be squeezed; Step S120: using an extrusion device to squeeze the concavo-convex rock mass from the cut to be squeezed, so that the concavo-convex rock mass is broken and falls off; Step S130: repeating the steps S110 to S120 until a preset excavation depth is reached; Wherein, in the step S120, a linear drive device is used to drive multiple extrusion devices installed on a free-face tunneling machine or a full-face tunneling machine to move linearly along the depth direction of the incision to be extruded so as to extrude the concave-convex rock mass, and the arrangement positions of the multiple extrusion devices correspond to the positions of the incision to be extruded so as to extrude from the free surface of the incision to be extruded so as to break the concave-convex rock mass from the root; wherein the extrusion device is a wedge block, and the wedge block has an extrusion thickness greater than the width of the incision to be extruded, and the thickness of the wedge block gradually decreases from the rear end to the front end, and the front end is an end close to the incision to be extruded.

2. The tunnel construction method using laser rock breaking as claimed in claim 1, characterized in that: In the step S110, a plurality of parallel laser emitting devices are used to cooperatively emit lasers to the tunnel face, so as to perform parallel cooperative cutting on the tunnel face along a cross track or a parallel track.

3. The tunnel construction method using laser rock breaking as claimed in claim 1, characterized in that: Also includes: Step S101: designing a tunnel cross-section profile to obtain a tunnel cross-section profile design drawing; Step S102: designing the laser scanning range and the arrangement of the extrusion device according to the tunnel section profile design drawing; Step S103: excavating the tunnel cross-section profile according to the tunnel cross-section profile design drawing.

4. The tunnel construction method using laser rock breaking as claimed in claim 3, characterized in that: Also includes: Step S104: scanning the tunnel cross-section profile to obtain a tunnel cross-section profile image; Step S105: Compare the tunnel cross-section profile image with the tunnel cross-section profile design drawing. If the shapes of the two are inconsistent, trim the tunnel cross-section profile until the tunnel cross-section profile is consistent with the shape of the tunnel cross-section profile design drawing.

5. The tunnel construction method using laser rock breaking as claimed in claim 4, characterized in that: In the step S104, a scanning device is used to scan the tunnel cross-section profile; In the step S105, a host computer is used to form a three-dimensional model of the tunnel cross-section profile, and the three-dimensional model is compared with the tunnel cross-section profile design drawing.

6. The tunnel construction method using laser rock breaking as claimed in claim 3, characterized in that: In step S103, a free-face tunnel boring machine or a full-face tunnel boring machine is used to excavate the tunnel section profile.

7. The tunnel construction method using laser rock breaking according to any one of claims 1 to 6, characterized in that: In the step S110, a laser installed on a free-face tunneling machine or a full-face tunneling machine is used to emit laser light, and the laser is formed by connecting a plurality of laser generating units in parallel.

8. The tunnel construction method using laser rock breaking according to any one of claims 1 to 6, characterized in that: In step S110, the laser power, laser light source shape, laser target distance, laser scanning angle and laser cutting speed are set according to the geological conditions.

Images