Bedding rock slope protection structure and construction method thereof

Abstract

The invention discloses a bedding rock slope protection structure and a construction method thereof. The bedding rock slope protection structure comprises grouting holes (1), anchor cables (2), prefabricated nodes (3), prefabricated continuous beams (4), cast-in-place lap joints (5) and multiple anchor cable linkage devices (7). The prefabricated joints (3) and the prefabricated continuous beams (4) are connected into a frame beam structure (6) through cast-in-place lap joints (5). The anchor cables (2) are installed in grouting holes (1) formed after grouting before mountain excavation to form a multi-anchor-cable structure, penetrate through anchoring holes (31) of the prefabricated nodes (3) after mountain excavation, are tensioned through the multi-anchor-cable linkage devices (7) connected with the ends and then are anchored to the prefabricated nodes (3), and the anchor cables, the frame beam structure and a rock mass form a whole. According to the method, the anchor cables are installed through punching and grouting before excavation, the safety coefficient of the excavation process is improved, through the synergistic effect of multiple anchor cable linkage devices, the slope is evenly stressed at different depths, the integrity of a protection structure is enhanced, and the long-term stability of the slope is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of slope stability, and more specifically, relates to a bedding rock slope protection structure and a construction method thereof. Background Art

[0002] Bedding rock slope refers to a layered rock slope in which the direction of the rock strata is basically consistent with the direction of the slope, and the inclination of the rock strata is the same as the slope direction. It is composed of rock strata of different lithologies. These rock strata have formed a layered structure under geological action. Under the action of external loads or natural factors (such as rainfall, earthquakes, etc.), bedding slippage is prone to occur, resulting in slope instability. The stability of the slope is directly related to the safety of engineering construction and the safety of the surrounding environment. Therefore, it is of great significance to protect and manage the bedding slope.

[0003] In order to solve the stability problem of bedding rock slopes, a variety of protection and management technologies are often used in engineering, mainly including two categories: flexible protection technology and rigid protection technology. Flexible protection technology mainly includes vegetation protection, geosynthetics protection, etc. Rigid protection technology mainly includes retaining walls, anti-slide piles, spray anchor support and steel mesh support, such as the patent document with publication number CN108755716B, which discloses a comprehensive protection and management method for water-containing and easily weathered rock bedding slopes. The present invention forms the first to Nth steps by mining on the slope surface, constructs drainage ditches at the bottom of the slope surface, constructs drainage holes on the slope surface to drain the accumulated water inside the steps, and constructs intercepting ditches on the top of the slope; then constructs grouting holes on the slope surface to integrate the rock fracture zone; then uses miscellaneous clay to spread on the top of the slope, and then rolls it; finally, constructs short anchor rods on the slope surface, anchors them by full-hole grouting, and uses concrete to hang mesh and spray the slope.

[0004] This invention fundamentally improves the stability of the slope through a combination of multiple protection schemes, including drainage schemes through drainage holes, water blocking by curtains, and slope spraying with anchor rods and nets, cuts off the contact between weathered rocks and the atmosphere, sunlight, and water, prevents weathering damage to the slope rock mass, gives full play to the strength of the rock mass itself, eliminates the key role of water in slope sliding, and increases the long-term stability of the slope. However, this scheme is to carry out protection after the slope is excavated, which is easy to disturb the slope surface during construction, causing disasters such as landslides. Summary of the invention

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a layered rock slope protection structure and a construction method thereof. Before excavating the mountain, holes are drilled and grouting is performed at the top of the slope perpendicular to the mountain and at the back of the slope along the direction of the rock layer. Anchor cables are inserted into the grouting holes of different depths after grouting to form a multiple anchor cable structure, which bonds the rock layer into a whole and improves the safety factor during excavation. After excavation, the prefabricated nodes and prefabricated continuous beams are connected to form a frame beam structure through cast-in-place lap joints, and the anchor cables are passed through the anchor holes on the prefabricated nodes. They are tensioned and anchored to the prefabricated nodes through a multiple anchor cable linkage device connected to the ends of the anchor cables to form a whole with the frame beam structure and the rock mass, thereby enhancing the integrity of the slope protection structure. Through the synergistic effect of multiple layers of anchor cables, stress is evenly applied to different depths of the slope, the slope surface is protected, and the long-term stability of the slope is improved.

[0006] In order to achieve the above-mentioned object, according to one aspect of the present invention, there is provided a bedding rock slope protection structure, comprising grouting holes, anchor cables, prefabricated nodes evenly arranged on the slope surface after excavation, prefabricated continuous beams arranged to match the prefabricated nodes, cast-in-place lap joints connecting the prefabricated nodes and the prefabricated continuous beams, and a multiple anchor cable linkage device; wherein,

[0007] The prefabricated node includes a through anchor hole arranged in the center and node reserved steel bars reserved at the end;

[0008] The prefabricated continuous beam includes reserved steel bars for the continuous beam at both ends;

[0009] The prefabricated node and the prefabricated continuous beam are connected by the reserved steel bars of the node and the reserved steel bars of the continuous beam, and then concrete is poured to form the cast-in-place lap joint to form a frame beam structure;

[0010] The anchor cables are installed in the grouting holes at different depths before and after grouting in the mountain excavation to form a multiple anchor cable structure, thereby improving the safety factor during the excavation process. After the slope is excavated, the ends of the anchor cables are passed through the anchor holes on the prefabricated nodes and connected through the multiple anchor cable linkage device. After prestressing, they are anchored on the prefabricated nodes to form a whole with the frame beam structure and the rock mass, thereby protecting the slope surface and improving the overall anti-slip ability and stability of the slope.

[0011] Furthermore, the node reserved steel bars of the prefabricated node and the continuous beam reserved steel bars of the prefabricated continuous beam are connected by binding or welding.

[0012] Furthermore, the grouting holes include grouting holes at different depths along the rock layer and grouting holes at the top of the slope perpendicular to the mountain.

[0013] Furthermore, it is characterized in that the anchor cables are made of high-strength steel cables or composite materials, and each layer of the anchor cables is fixed by grouting after drilling.

[0014] Furthermore, the prefabricated nodes are divided into cross-shaped prefabricated nodes, T-shaped prefabricated nodes, and L-shaped prefabricated nodes, and the specific shapes can be adjusted according to the actual situation on site.

[0015] Furthermore, the prefabricated node also includes a lap joint with the continuous beam arranged at a peripheral protruding portion, and longitudinal and transverse lap steel bars are arranged inside the lap joint.

[0016] Furthermore, the prefabricated continuous beam also includes a prefabricated beam, in which a full-length steel bar is arranged.

[0017] Furthermore, the multiple anchor cable linkage device includes a sliding connection structure, which is installed on the tensioning ends of the anchor cables at different depths along the rock layer, and is used to synchronously adjust the stress state of the anchor cables in each layer when the stress changes, so as to avoid failure of the anchor cables due to excessive local stress.

[0018] Furthermore, the multiple anchor cable linkage device also includes a tension adjustment system for controlling the tensioning force of each layer of the anchor cables through a hydraulic adjustment device to ensure overall force balance.

[0019] According to another aspect of the present invention, a construction method of a bedding rock slope protection structure is provided, which is implemented by applying the bedding rock slope protection structure described above, and comprises the following steps:

[0020] S100: Geological survey. Through field exploration, geological mapping, drilling sampling, etc., the geological structure, lithology, geological age, stratigraphic characteristics, fault distribution, hydrological conditions, etc. of the slope are investigated to analyze the stability of the slope and the potential geological disaster risks;

[0021] S200: Drilling, grouting and anchor cable installation. According to the design requirements, holes are drilled on the back of the mountain along the sliding surface of the rock layer and on the top of the slope perpendicular to the mountain to form grouting holes and grouting. Anchor cables are inserted into the grouting holes at different depths after grouting to form a multi-anchor cable structure;

[0022] S300: preparing prefabricated nodes and prefabricated continuous beams in a factory or on site;

[0023] S400: mountain excavation: according to the slope design requirements, mountain excavation is carried out to control the slope gradient, slope shape and grooves matching the prefabricated nodes and prefabricated continuous beams to form a predetermined slope shape;

[0024] S500: installing prefabricated nodes, prefabricated continuous beams and multiple anchor cable linkage devices, installing prefabricated nodes and prefabricated continuous beams to corresponding groove positions on the slope, accurately passing anchor cables through anchor holes on prefabricated nodes, and connecting and installing anchor cable linkage devices at the ends of anchor cables;

[0025] S600: Lap joint casting, connecting the reserved steel bars by tying or welding, pouring concrete on the lap joints, connecting all prefabricated nodes and prefabricated continuous beams into a whole, and forming a frame beam structure;

[0026] S700: Anchor cable prestressing and locking. After the concrete lap cast-in-place section reaches the design strength, each layer of anchor cables is prestressed synchronously through a multiple anchor cable linkage device, and the prestressed anchor cables are locked using anchors.

[0027] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0028] 1. The layered rock slope protection structure of the present invention, before the slope is excavated, is used to bond the rock layers into a whole by drilling holes and injecting grout at the top of the slope perpendicular to the mountain and at the back of the mountain along the direction of the rock layers, thereby solving the problem of landslides in the mountain during the construction process and greatly improving the mountain's anti-slip performance.

[0029] 2. The bedding rock slope protection structure of the present invention solves the problem that the traditional construction method of anchoring is carried out after the slope is excavated, resulting in a long construction period of the protection structure and long-term exposure of the excavation surface, by driving anchor cables into the grouting holes before the slope is excavated, and further improves the safety factor during the excavation process.

[0030] 3. The multi-anchor linkage design of the present invention enables the different depths of the slope to be evenly stressed through the synergistic effect of multiple layers of anchor cables, which not only enhances the integrity of the slope protection structure, but also effectively prevents slope sliding and improves the long-term stability of the slope. It is particularly suitable for the protection of bedding rock slopes under complex geological conditions.

[0031] 4. The bedding rock slope protection structure of the present invention solves the quality problems caused by on-site pouring and inadequate vibration in traditional construction methods by prefabricating prefabricated nodes and prefabricated continuous beams, and effectively improves the construction quality.

[0032] 5. The layered rock slope protection structure of the present invention adopts a complete construction method of grouting and anchoring before excavation and installing prefabricated nodes and prefabricated continuous beams after excavation. All prefabricated nodes and prefabricated continuous beams are connected as a whole and connected to the rock mass through anchor cables, which solves the risk of long-term exposure of the excavation surface in traditional construction methods, which is easy to cause new disasters, and greatly shortens the construction period of the frame beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a cross-sectional schematic diagram of a bedding rock slope protection structure according to an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of drilling and grouting according to an embodiment of the present invention;

[0035] Figure 3 This is a three-view schematic diagram of a cross prefabricated node according to an embodiment of the present invention;

[0036] Figure 4 This is a three-view schematic diagram of a T-shaped prefabricated node according to an embodiment of the present invention;

[0037] Figure 5 This is a three-view schematic diagram of an L-shaped prefabricated node according to an embodiment of the present invention;

[0038] Figure 6 This is a three-view schematic diagram of a prefabricated continuous beam according to an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of burying prefabricated nodes according to an embodiment of the present invention;

[0040] Figure 8 It is a schematic plan view of the slope frame beam structure according to an embodiment of the present invention;

[0041] Fig. 9 The present invention is a schematic diagram of a process flow of a method for constructing a bedding rock slope protection structure according to an embodiment of the present invention.

[0042] In all the drawings, the same figure numbers represent the same technical features, specifically: 1-grouting hole, 11-grouting hole along the rock layer, 12-grouting hole on the top of the slope perpendicular to the mountain, 2-anchor cable, 3-prefabricated node, 31-anchor hole, 32-lap joint with continuous beam, 33-node reserved steel bars, 4-prefabricated continuous beam, 41-prefabricated beam, 42-continuous beam reserved steel bars, 5-cast-in-place lap joint, 6-frame beam structure, 7-multiple anchor cable linkage device, 8-designed excavation line, 9-mountain rock layer structure, 10-road cutting ditch. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0045] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0046] In this patent, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, the elements defined by the sentence "includes..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0047] like Figure 1-8 The embodiment of the present invention provides a bedding rock slope protection structure, comprising a grouting hole 1, an anchor cable 2, prefabricated nodes 3 evenly arranged on the slope surface after excavation, a prefabricated continuous beam 4 arranged to match the prefabricated node 3, a cast-in-place lap joint 5 connecting the prefabricated node (3) and the prefabricated continuous beam (4), and a multiple anchor cable linkage device 7. The grouting hole 1 is set by drilling holes on the back of the mountain according to geological survey results before the mountain is excavated, and the anchor cable 2 is installed after grouting in the grouting hole 1 to form a reinforced concrete anchor. The precast cable is then cast, and the slope is excavated according to the designed excavation boundary line 6. The precast node 3 and the precast continuous beam 4 are connected into a whole through the cast-in-place lap joint 5 to form a frame beam structure 6, and the anchor cable 2 is accurately passed through the precast node 3 at different depths along the rock layer. The anchor cable linkage device 7 is installed at the end of the anchor cable 2 at different layers, and each layer of anchor cables is graded and synchronously prestressed and locked. The interaction between the anchor cable, frame beam and rock mass is reinforced by grouting to achieve slope protection and enhance slope stability. The structure of the present invention performs grouting and driving anchor cables into the sliding surface of the slope for reinforcement before the excavation of the slope, and uses precast component frame beams after excavation, which effectively reduces the risk of landslides during the slope excavation process, and the prefabrication method ensures the construction quality of the slope protection and shortens the construction period of the frame beam.

[0048] like Figure 2As shown, the grouting holes 1 include grouting holes 11 of different depths along the rock layer and grouting holes 12 at the top of the slope perpendicular to the mountain. Grouting is used to enhance the cohesion of the mountain rock layer and fill the cracks and gaps in the slope, thereby enhancing the integrity and connectivity of the slope rock mass, thereby improving the stability of the slope. The drilling depth of the grouting holes 12 at the top of the slope perpendicular to the mountain should be 1 to 2 meters below the rock layer dip line of the road cut ditch 10 at the edge of the road surface, and the depth of the grouting holes 11 along the rock layer at the back of the mountain corresponding to the construction excavation surface should be 0.5 to 1 meter outside the designed excavation line.

[0049] like Figure 3-5 As shown, the prefabricated nodes 3 are divided into three shapes: cross-shaped prefabricated nodes, T-shaped prefabricated nodes, and L-shaped prefabricated nodes (the specific shapes can be adjusted according to the actual situation on site). Each of the prefabricated nodes 3 is provided with longitudinal and transverse lap steel bars, and a through anchor hole 31 is provided in the center. The anchor cable 2 is tensioned through the anchor hole 31 and fixed to the prefabricated node 3 by an anchor. The protruding parts around the prefabricated node 3 are lap joints 32 with the continuous beam, and node reserved steel bars 33 are provided at the ends thereof to facilitate the subsequent connection with the prefabricated continuous beam 4.

[0050] like Figure 6 As shown, the prefabricated continuous beam 4 includes a prefabricated beam 41, which is provided with a through-length steel bar inside, and has reserved steel bars 42 for the continuous beam at both ends, which are connected to the reserved node steel bars 33 of the prefabricated node 3 by binding or welding.

[0051] like Figure 7-8 As shown, the prefabricated node 3 and the prefabricated continuous beam 4 are installed in the corresponding groove positions excavated in the slope, the node reserved steel bars 33 and the continuous beam reserved steel bars 42 are connected by binding or welding, and the cast-in-place lap joint 5 is formed by pouring concrete on the lap joint on site, and the prefabricated node 3 and the prefabricated continuous beam 4 are connected as a whole to form a frame beam structure 6. During the installation process, attention should be paid to maintaining the horizontal and vertical accuracy of the prefabricated node 3 to ensure that it is in close contact with the slope rock and soil, and the anchor cable 2 that penetrates the mountain should accurately pass through the anchor hole 31.

[0052] The multiple anchor cable linkage device 7 is installed at the end of the anchor cable 2 passing through the prefabricated node 3, and includes a sliding connection structure and a tension adjustment system. The sliding connection structure is used to synchronously adjust the stress state of the anchor cables 2 at each layer when the stress changes, so as to avoid failure of the anchor cables due to excessive local stress; the tension adjustment system is used to control the tension of the anchor cables (2) at each layer through a hydraulic adjustment device. When the stress of a certain layer of anchor cables changes, the tension of other layers of anchor cables is automatically adjusted to maintain balance, so as to ensure overall force balance.

[0053] The embodiment of the present invention solves the problem that the mountain is prone to landslides during the construction process by drilling holes and grouting before excavation and setting anchor cables in layers. Prefabricated frame beams are installed after the mountain is excavated, which shortens the construction period of the frame beams. Multiple anchor cable linkage devices are installed to ensure that each layer of anchor cables can be adjusted synchronously to achieve uniform force on different depths of the slope, thereby improving the overall anti-slip ability.

[0054] Combination Figure 1-8 ,like Fig. 9 As shown, the present invention provides a construction method of a bedding rock slope protection structure, comprising the following steps:

[0055] S100: Geological survey. Investigate the geological structure, lithology, geological age, stratigraphic characteristics, fault distribution, hydrological conditions, etc. of the slope, and analyze the stability of the slope and potential geological disaster risks.

[0056] S200: drilling, grouting and anchor installation.

[0057] S201: Drilling location design: Based on the geological survey results, drill holes along the rock layer sliding surface near the top of the designed road cut slope and on the back of the mountain corresponding to the construction excavation surface. These drilling locations should be able to control slope sliding and deformation and improve slope stability. Ensure that the drilling depth and accuracy meet the design requirements. The drilling depth at the top of the designed road cut slope should be 1 to 2 meters below the inclination line of the ditch rock layer, and the hole depth at the back of the mountain corresponding to the construction excavation surface should be 0.5 to 1 meter outside the designed excavation line.

[0058] S202: Grouting: According to the rock and soil characteristics of the slope and the requirements for grouting effect, the reasonable grouting material ratio and the appropriate grouting pressure and speed are determined through experiments to ensure the grouting effect.

[0059] S203: Anchor cable installation: Insert anchor cables into grouting holes of different depths after grouting to form a multi-anchor cable structure to further improve the anti-sliding force of the rock formation. During the installation process, attention should be paid to the installation depth to ensure that the anchor cables are tightly combined with the rock and soil.

[0060] S300: Fabrication of prefabricated nodes and prefabricated continuous beams. Prefabricated nodes and continuous beams are prepared in factories or on site. Prefabricated components should meet the design strength, stiffness and durability requirements.

[0061] S400: Mountain excavation, according to the slope protection design requirements, mountain excavation is carried out to form a predetermined slope shape. During the excavation process, the slope gradient, slope shape and grooves matching the prefabricated nodes and prefabricated continuous beams should be strictly controlled in accordance with the design requirements to ensure the excavation quality.

[0062] S500: Installation of prefabricated nodes, prefabricated continuous beams and multiple anchor cable linkage devices. Install the prefabricated nodes and prefabricated continuous beams to the corresponding groove positions of the slope, accurately pass the anchor cables through the anchor holes on the prefabricated nodes, and connect and install the anchor cable linkage devices at the ends of the anchor cables.

[0063] During the installation process, attention should be paid to maintaining the horizontal and vertical accuracy of the nodes, ensuring that the nodes are in close contact with the slope rock and soil. At the same time, the anchor cables that penetrate the mountain should accurately pass through the anchor holes.

[0064] S600: Lap joint casting, connecting the reserved steel bars by tying or welding, pouring concrete on the lap joints, connecting all prefabricated nodes and prefabricated continuous beams into a whole, and forming a frame beam structure;

[0065] S700: Anchor cable prestressing and locking. After the concrete lap cast-in-place section reaches the design strength, each layer of anchor cables is prestressed synchronously. The tension of each layer of anchor cables is evenly distributed through multiple anchor cable linkage devices, and the anchor cable tension is fixed with anchors to improve the bearing capacity and durability of the anchor cables. During the tensioning process, attention should be paid to the tension, elongation and stress loss of the anchor cables to ensure that the performance of the anchor cables meets the design requirements. The qualified anchor cables are locked to prevent prestress loss. When locking, attention should be paid to the locking force, locking position and anti-corrosion treatment of the anchor cables to ensure the long-term stability of the anchor cables.

[0066] The following further discloses a specific embodiment of the present invention based on a construction method of a bedding rock slope protection structure of the present invention.

[0067] Embodiment 1 of the present invention: Protection of bedding rock slopes in mountainous road projects

[0068] In a certain mountain road project, the dip of the slope rock layer is 30°∠30°, the road plane is located on a flat curve, and the angle between the rock layer and the line slope is about 10° to 25°. The project adopts a graded slope design, with a road cut slope height of 6 to 28.5m and a slope section length of about 210m. Since the angle between the rock layer and the slope is small, it is a layered slope. During the excavation process, the rock layer is exposed or in rainfall, the slope may slide. In order to improve the stability of the slope, the engineering team adopted the construction method of the layered rock slope protection structure of the present invention before and after construction. The specific steps are as follows:

[0069] S100: Geological survey. Through field exploration, geological mapping, drilling sampling and indoor analysis, it was determined that the slope was slightly to moderately weathered schist along the bedding, which was prone to sliding under excavation and precipitation conditions.

[0070] S200: drilling, grouting and anchor installation.

[0071] S201: Drilling location design: According to the geological survey results, drill holes along the rock layer sliding surface near the top of the designed road cutting slope and on the back of the mountain corresponding to the construction excavation surface. The drilling depth at the top of the designed road cutting slope is 1 meter below the dip line of the ditch rock layer, and the hole depth at the back of the mountain corresponding to the construction excavation surface is 0.8 meters outside the designed excavation line.

[0072] S202: Grouting: According to the rock and soil characteristics of the slope, cement slurry is used as the grouting material. The water-cement ratio of the cement slurry is 0.6 and the grouting pressure is 0.8MPa.

[0073] S203: Anchor cable installation: Insert anchor cables into grouting holes of different depths after grouting, and perform secondary grouting. The grouting pressure is 1.5MPa to form a multi-anchor cable structure to further improve the anti-sliding force of the rock formation. During the installation process, attention should be paid to the installation depth to ensure that the anchor cables are closely combined with the rock and soil.

[0074] S300: Fabrication of prefabricated nodes and prefabricated continuous beams. Cross-shaped prefabricated nodes, T-shaped prefabricated nodes, L-shaped prefabricated nodes, and prefabricated continuous beams are prepared in the factory or on site. The prefabricated components should meet the design strength, stiffness, and durability requirements.

[0075] S400: Mountain excavation. According to the slope design excavation slope, the mountain is excavated to form a stepped slope shape. During the excavation process, the slope gradient, slope shape and grooves matching the prefabricated nodes and prefabricated continuous beams should be strictly controlled according to the design requirements to ensure the excavation quality.

[0076] S500: Installation of prefabricated nodes, prefabricated continuous beams and multiple anchor cable linkage devices. Install various prefabricated nodes and prefabricated continuous beams to the corresponding groove positions on the slope, and accurately pass the anchor cables through the anchor holes on the prefabricated nodes, and connect and install the anchor cable linkage device at the ends of the anchor cables. During the installation process, attention should be paid to maintaining the horizontal and vertical accuracy of the nodes, ensuring that the nodes are in close contact with the slope rock and soil, and the anchor cables that penetrate the mountain should accurately pass through the anchor holes.

[0077] S600: Lap joint casting, connecting the reserved steel bars by tying or welding, pouring concrete on the lap joints, connecting all prefabricated nodes and prefabricated continuous beams into a whole, and forming a frame beam structure;

[0078] S700: Anchor cable prestressing and locking. After the concrete lap cast-in-place section reaches the design strength, each layer of anchor cables is prestressed synchronously. The tension of each layer of anchor cables is evenly distributed through multiple anchor cable linkage devices, and the anchor cable tension is fixed with anchors to improve the bearing capacity and durability of the anchor cables. During the tensioning process, attention should be paid to the tension, elongation and stress loss of the anchor cables to ensure that the performance of the anchor cables meets the design requirements. The qualified anchor cables are locked to prevent prestress loss. When locking, attention should be paid to the locking force, locking position and anti-corrosion treatment of the anchor cables to ensure the long-term stability of the anchor cables.

[0079] S800: Construction of surface layer between frame beams. The prefabricated beam frames are protected by spraying foreign soil to reduce rainwater erosion.

[0080] Embodiment 2 of the present invention: Protection design of a high soft rock slope in a tunnel

[0081] In a tunnel project, a high soft rock slope is located on the left side of the tunnel according to the design line. The terrain is undulating and the natural slope is between 35-50°. Considering the formation composition and hydrogeological conditions, the engineering team adopted the construction method of the bedding rock slope protection structure of the present invention. The specific steps are as follows:

[0082] S100: Geological survey. Through field exploration, geological mapping, drilling sampling and indoor analysis, it was determined that the slope was a layer of fully weathered muddy sandstone intercalated with shale, which was prone to sliding along the weak layer under artificial excavation disturbance and precipitation conditions.

[0083] S200: drilling, grouting and anchor installation.

[0084] S201: Drilling location design: According to the geological survey results, before excavation, grouting holes are drilled perpendicular to the mountain near the top of the designed cutting slope, and holes are drilled along the sliding surface of the rock layer on the back of the mountain corresponding to the construction excavation surface. The drilling depth at the top of the designed cutting slope is 1.5 meters below the inclination line of the rock layer in the tunnel ditch, and the hole depth at the back of the mountain corresponding to the construction excavation surface is 1 meter outside the designed excavation line.

[0085] S202: Grouting: According to the rock and soil characteristics of the slope, cement slurry is used as the grouting material. The water-cement ratio of the cement slurry is 0.6 and the grouting pressure is 1MPa.

[0086] S203: Anchor cable installation: Insert anchor cables into grouting holes of different depths after grouting, and perform secondary grouting. The grouting pressure is 2MPa to form a multi-anchor cable structure to further improve the anti-sliding force of the rock formation. During the installation process, attention should be paid to the installation depth to ensure that the anchor cables are closely combined with the rock and soil.

[0087] S300: Fabrication of prefabricated nodes and prefabricated continuous beams. Cross-shaped prefabricated nodes, T-shaped prefabricated nodes, L-shaped prefabricated nodes, and prefabricated continuous beams are prepared in the factory or on site. The prefabricated components should meet the design strength, stiffness, and durability requirements.

[0088] S400: Mountain excavation. According to the slope design excavation slope, the mountain is excavated to form a stepped slope shape. During the excavation process, the slope gradient, slope shape and grooves matching the prefabricated nodes and prefabricated continuous beams should be strictly controlled according to the design requirements to ensure the excavation quality.

[0089] S500: Installation of prefabricated nodes, prefabricated continuous beams and multiple anchor cable linkage devices. Install various prefabricated nodes and prefabricated continuous beams to the corresponding groove positions on the slope, and accurately pass the anchor cables through the anchor holes on the prefabricated nodes, and connect and install the anchor cable linkage device at the ends of the anchor cables. During the installation process, attention should be paid to maintaining the horizontal and vertical accuracy of the nodes, ensuring that the nodes are in close contact with the slope rock and soil, and the anchor cables that penetrate the mountain should accurately pass through the anchor holes.

[0090] S600: Lap joint casting, connecting the reserved steel bars by tying or welding, pouring concrete on the lap joints, connecting all prefabricated nodes and prefabricated continuous beams into a whole, and forming a frame beam structure;

[0091] S700: Anchor cable prestressing and locking. After the concrete lap cast-in-place section reaches the design strength, each layer of anchor cables is prestressed synchronously. The tension of each layer of anchor cables is evenly distributed through multiple anchor cable linkage devices, and the anchor cable tension is fixed with anchors to improve the bearing capacity and durability of the anchor cables. During the tensioning process, attention should be paid to the tension, elongation and stress loss of the anchor cables to ensure that the performance of the anchor cables meets the design requirements. The qualified anchor cables are locked to prevent prestress loss. When locking, attention should be paid to the locking force, locking position and anti-corrosion treatment of the anchor cables to ensure the long-term stability of the anchor cables.

[0092] S800: Surface layer construction between frame beams. Net-hanging soil spraying is used between prefabricated beam frames to reduce rainwater erosion.

[0093] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bedding rock slope protection structure, characterized in that: The invention comprises grouting holes (1), anchor cables (2), prefabricated nodes (3) evenly arranged on the slope surface after excavation, prefabricated continuous beams (4) arranged to match the prefabricated nodes (3), cast-in-place lap joints (5) connecting the prefabricated nodes (3) and the prefabricated continuous beams (4), and a multiple anchor cable linkage device (7); wherein: The prefabricated node (3) comprises a through anchor hole (31) arranged at the center and node reserved steel bars (33) reserved at the end; The prefabricated continuous beam (4) comprises reserved continuous beam steel bars (42) at both ends; The prefabricated node (3) and the prefabricated continuous beam (4) are connected by the node reserved steel bars (33) and the continuous beam reserved steel bars (42), and then concrete is poured to form the cast-in-place lap joint (5) to form a frame beam structure (6); The anchor cable (2) is installed in the grouting hole (1) at different depths before and after grouting of the mountain body, forming a multiple anchor cable structure, thereby improving the safety factor during the excavation process. After the slope is excavated, the end of the anchor cable (2) is passed through the anchor hole (31) on the prefabricated node (3), and connected through the multiple anchor cable linkage device (7). After prestressing, it is anchored on the prefabricated node (3), forming a whole with the frame beam structure (6) and the rock mass, protecting the slope surface, and improving the overall anti-slip ability and stability of the slope.

2. A bedding rock slope protection structure according to claim 1, characterized in that: The node reserved steel bars (33) of the prefabricated node (3) and the continuous beam reserved steel bars (42) of the prefabricated continuous beam (4) are connected by binding or welding.

3. The bedding rock slope protection structure according to claim 1, characterized in that: The grouting holes (1) include grouting holes (11) at different depths along the rock layer and grouting holes (12) at the top of the slope perpendicular to the mountain.

4. A bedding rock slope protection structure according to any one of claims 1 to 3, characterized in that: The anchor cables (2) are made of high-strength steel cables or composite materials, and each layer of the anchor cables (2) is fixed by grouting after drilling.

5. A bedding rock slope protection structure according to any one of claims 1 to 3, characterized in that: The prefabricated nodes (3) are divided into cross-shaped prefabricated nodes, T-shaped prefabricated nodes, and L-shaped prefabricated nodes, and the specific shapes can be adjusted according to the actual situation on site.

6. A bedding rock slope protection structure according to claim 5, characterized in that: The prefabricated node (3) also includes a lap joint (32) arranged at a peripheral protruding portion and connected to the continuous beam, and longitudinal and transverse lap steel bars are arranged inside the lap joint.

7. A bedding rock slope protection structure according to any one of claims 1 to 3, characterized in that: The prefabricated continuous beam (4) further comprises a prefabricated beam (41) which is provided with a continuous steel bar.

8. A bedding rock slope protection structure according to any one of claims 1 to 3, characterized in that: The multiple anchor cable linkage device (7) comprises a sliding connection structure, which is installed at the tensioning end of the anchor cable (2) at different depths along the rock layer, and is used to synchronously adjust the stress state of the anchor cable (2) in each layer when the stress changes, so as to avoid failure of the anchor cable due to excessive local stress.

9. A bedding rock slope protection structure according to claim 8, characterized in that: The multiple anchor cable linkage device (7) also includes a tension adjustment system for controlling the tensioning force of each layer of the anchor cables (2) through a hydraulic adjustment device to ensure overall force balance.

10. A construction method of a bedding rock slope protection structure, implemented by using a bedding rock slope protection structure as claimed in any one of claims 1 to 9, characterized in that: The steps include: S100: Geological survey. Through field exploration, geological mapping, drilling sampling, etc., the geological structure, lithology, geological age, stratigraphic characteristics, fault distribution, hydrological conditions, etc. of the slope are investigated to analyze the stability of the slope and the potential geological disaster risks; S200: Drilling, grouting and anchor cable installation. According to the design requirements, holes are drilled on the back of the mountain along the sliding surface of the rock layer and on the top of the slope perpendicular to the mountain to form grouting holes and grouting. Anchor cables are inserted into the grouting holes at different depths after grouting to form a multi-anchor cable structure; S300: preparing prefabricated nodes and prefabricated continuous beams in a factory or on site; S400: mountain excavation: according to the slope design requirements, mountain excavation is carried out to control the slope gradient, slope shape and grooves matching the prefabricated nodes and prefabricated continuous beams to form a predetermined slope shape; S500: installing prefabricated nodes, prefabricated continuous beams and multiple anchor cable linkage devices, installing prefabricated nodes and prefabricated continuous beams to corresponding groove positions on the slope, accurately passing anchor cables through anchor holes on prefabricated nodes, and connecting and installing anchor cable linkage devices at the ends of anchor cables; S600: Lap joint casting, connecting the reserved steel bars by tying or welding, pouring concrete on the lap joints, connecting all prefabricated nodes and prefabricated continuous beams into a whole, and forming a frame beam structure; S700: Anchor cable prestressing and locking. After the concrete lap cast-in-place section reaches the design strength, each layer of anchor cables is prestressed synchronously through a multiple anchor cable linkage device, and the prestressed anchor cables are locked using anchors.

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