Novel protection and reinforcement integrated structure suitable for fractured rock slope

Abstract

The utility model provides a novel protection and reinforcement integrated structure suitable for a fractured rock mass slope. The novel protection and reinforcement integrated structure comprises an anchor rod frame system, system anchor rods, a steel bar protection net, sprayed concrete and a vegetation layer. The anchor rod frame system comprises a reinforced concrete frame and node anchor rods; a node anchor rod is arranged at each frame node position, the node anchor rods are obliquely arranged in the broken rock slope, one end of each node anchor rod is anchored to the deep position of the stable bed rock, and the other end of each node anchor rod is connected with the reinforced concrete frame; arranging system anchor rods on the slope surface of the broken rock slope according to a certain row distance; a reinforcing steel bar protective net is laid at the bottom of the anchor rod frame system, and sprayed concrete is sprayed on the reinforcing steel bar protective net; and a vegetation layer is laid in each grid of the reinforced concrete frame. The structure can effectively cope with the instability problem of the fractured rock mass slope under the weathering and unloading effects, has the advantages of being high in stability, strong in durability, good in adaptability, ecological, environmentally friendly and the like, and has wide application prospects in the field of slope protection and reinforcement of water-power engineering.

Description

Technical Field

[0001] This utility model relates to the field of slope protection and reinforcement technology, specifically to a novel integrated structure for protection and reinforcement of fractured rock slopes. Background Technology

[0002] In the field of water conservancy and hydropower engineering, weathering and unloading often lead to rock slope fracturing and reduced stability. Weathering alters the mineral composition, structure, and texture of rocks, reducing their strength and integrity; unloading redistributes internal stresses within the rock mass, creating unloading fissures and further exacerbating the fracturing of the rock mass.

[0003] Traditional slope protection and reinforcement methods often have limitations, failing to achieve ideal protection effects on fractured rock slopes. For example, single anchor bolt support is insufficient to effectively restrain the overall deformation of fractured rock masses, and shotcrete with wire mesh is ineffective for reinforcing deep rock masses. Furthermore, these methods lack durability and adaptability in the face of long-term weathering and dynamic unloading changes, easily leading to slope protection and reinforcement structure failure, triggering geological disasters such as collapses and landslides, posing a serious threat to the safety of surrounding lives, property, and infrastructure. Moreover, they lack ecological adaptability and can no longer meet the needs of modern engineering construction. Therefore, a new integrated protection and reinforcement structure capable of effectively addressing fractured rock slopes under weathering and unloading is needed. Utility Model Content

[0004] In view of the shortcomings of the existing technology, this utility model provides a new integrated protection and reinforcement structure suitable for fractured rock slopes, which can effectively solve the above problems.

[0005] The technical solution adopted in this utility model is as follows:

[0006] This utility model provides a novel integrated structure for protection and reinforcement of fractured rock slopes, including: an anchor frame system, system anchors (5), steel reinforcement mesh (2), shotcrete (3), and vegetation layer (4);

[0007] The anchor frame system includes a reinforced concrete frame (1) and node anchors (6); the reinforced concrete frame (1) is a grid-like frame structure, including multiple grids, fixed to the slope surface of the fractured rock slope; at each frame node position of the reinforced concrete frame (1), the node anchors (6) are set, the node anchors (6) are inclinedly set in the fractured rock slope, one end is anchored deep in the stable bedrock, and the other end is connected to the reinforced concrete frame (1); on the slope surface of the fractured rock slope, the system anchors (5) are arranged at a certain spacing; at the bottom of the anchor frame system and on the slope surface of the fractured rock slope, the steel reinforcement protective net (2) is laid, and the steel reinforcement protective net (2) is sprayed with the shotcrete (3); in each grid of the reinforced concrete frame (1), the vegetation layer (4) is laid.

[0008] Preferably, the reinforced concrete frame (1) includes a crossbeam (1-1) and a longitudinal beam (1-2); the bottom of the reinforced concrete frame (1) is embedded into the slope of the broken rock slope to a depth of 10cm.

[0009] Preferably, the frame nodes of the reinforced concrete frame (1) include edge nodes and intermediate nodes; the edge nodes are hexagonal; and the intermediate nodes are octagonal.

[0010] Preferably, the node anchor (6) is a cement mortar anchor, anchor bar bundle, or anchor cable.

[0011] Preferably, the system anchor (5) is a cement mortar anchor. The system anchor (5) is inserted into the reinforcement hole of the broken rock slope, with an insertion length of not less than 95% of the design length and an exposed length of not less than 100mm. The exposed part of the system anchor (5) at the connection with the reinforced concrete frame (1) is firmly welded to the surface reinforcement of the reinforced concrete frame (1). The axial direction of the reinforcement hole of the system anchor (5) is perpendicular to the excavation outline.

[0012] Preferably, the thickness of the cement mortar protective layer of the anchor rod (5) of the system is not less than 20mm.

[0013] Preferably, the steel reinforcement protective net (2) is a single-layer steel reinforcement net or a double-layer steel reinforcement net, using smooth steel bars with a yield strength of not less than 300MPa, a diameter of 8mm, and a mesh size of 200mm×200mm. The net is constructed by manually binding the mesh. At the locations where the system anchor rod (5) and the node anchor rod (6) are located, the steel reinforcement protective net (2) is connected to the system anchor rod (5) and the node anchor rod (6) by binding. Other locations are fixed using U-shaped clips.

[0014] Preferably, the thickness of the sprayed concrete (3) is not less than 100 mm.

[0015] Preferably, the vegetation layer (4) is a humus bag, which includes a biodegradable woven bag and humus and grass seeds filled inside the woven bag; each bag contains 30-80 grams of grass seeds. The humus bags are laid on the slope from bottom to top in a staggered manner and are placed horizontally along the slope surface, with adjacent humus bags arranged closely together.

[0016] Preferably, it also includes a drainage system; the drainage system includes slope drainage holes (7), walkway drainage planting troughs (8), slope bottom drainage ditch (9) and slope top intercepting ditch (10);

[0017] The slope top intercepting ditch (10) is set along the top edge of the slope and is located 5m outside the slope excavation line. Its cross-sectional shape is an inverted trapezoid and it is made of mortar-grouted rubble or concrete.

[0018] The slope drainage hole (7) is drilled downward along the slope with an elevation angle of not less than 10°, a diameter of 50mm, a hole depth of 5m, and a row spacing of 3m. A 50mm diameter PVC rigid drainage pipe is installed in the slope drainage hole (7), wrapped with non-woven fabric, and extends into the bottom of the drainage hole. The pipe opening extends out of the reinforced concrete frame (1) or the shotcrete (3).

[0019] The horse trail drainage planting trough (8) is arranged along the entire horse trail and includes two functional areas: a horse trail drainage ditch and a planting trough. Its starting and ending points are connected to the slope top intercepting ditch (10).

[0020] The drainage ditch (9) at the bottom of the slope is set along the bottom edge of the slope. Its cross-sectional shape is rectangular and it is made of concrete. The side near the slope is an L-shaped retaining wall. PVC drainage pipes are pre-embedded inside at a certain spacing. The ends of the drainage pipes are wrapped with non-woven fabric, forming a bottom drainage planting trough.

[0021] The novel integrated protection and reinforcement structure for fractured rock slopes provided by this utility model has the following advantages:

[0022] This utility model's integrated protection and reinforcement structure can effectively address the instability problem of fractured rock slopes under weathering and unloading. It has advantages such as high stability, strong durability, good adaptability, and environmental friendliness, and has broad application prospects in the field of slope protection and reinforcement for hydropower projects. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0024] Figure 1 This is a plan view of a novel integrated protection and reinforcement structure for fractured rock slopes according to this utility model.

[0025] Figure 2 for Figure 1 Sectional view of AA in the middle;

[0026] Figure 3 for Figure 1 Cross-sectional view of the middle section (BB);

[0027] Figure 4 This is a schematic diagram of the slope greening and drainage system of this utility model;

[0028] Figure 5 This is a detailed drawing of the intermediate node provided by this utility model;

[0029] Figure 6 This is a detailed drawing of the edge node provided for this utility model.

[0030] In the diagram: 1. Reinforced concrete frame; 1-1. Horizontal beam; 1-2. Longitudinal beam; 2. Reinforcing mesh; 3. Shotcrete; 4. Vegetation layer; 5. System anchor bolts; 6. Node anchor bolts; 7. Slope drainage holes; 8. Walkway drainage planting trough; 9. Slope bottom drainage ditch; 10. Slope top intercepting ditch. Detailed Implementation

[0031] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0032] This utility model discloses a novel integrated protection and reinforcement structure for fractured rock slopes, comprising an anchor bolt (anchor bar bundle or anchor cable) frame system, system anchor bolts 5, steel reinforcement mesh 2, shotcrete 3, vegetation layer 4, and drainage system. This utility model effectively addresses the instability problem of fractured rock slopes under weathering and unloading, possessing advantages such as high stability, strong durability, good adaptability, and environmental friendliness, and has broad application prospects in the field of slope protection and reinforcement for hydropower projects.

[0033] The design features of each part are described in detail below:

[0034] Anchor frame system:

[0035] The anchor frame system, as the main load-bearing structure, includes a reinforced concrete frame 1 and multiple node anchors 6. The reinforced concrete frame 1 is a grid-like frame structure, including multiple grids, and is fixed to the slope surface of the fractured rock slope. The reinforced concrete frame 1 includes a crossbeam 1-1 and a longitudinal beam 1-2. The bottom of the reinforced concrete frame 1 is embedded into the slope of the fractured rock slope to a depth of 10cm. During construction, trench excavation is carried out on site, with a trench depth of 10cm and structural joints set every 10-15m.

[0036] The frame nodes of the reinforced concrete frame 1 include edge nodes and intermediate nodes; the edge nodes are hexagonal; and the intermediate nodes are octagonal.

[0037] At each frame node of the reinforced concrete frame 1, a node anchor 6 is installed. The node anchor 6 can be a cement mortar anchor, anchor bar bundle, or anchor cable. The node anchor 6 is inclinedly installed in the fractured rock slope, with one end anchored deep in the stable bedrock and the other end firmly connected to the reinforced concrete frame 1. The anchoring force is transferred to the slope surface through the reinforced concrete frame 1, forming a spatial force system, providing a supporting structure for slope protection, and effectively resisting the slope's sliding force and overturning moment.

[0038] System anchor bolts:

[0039] On the fractured rock slope, the system anchors 5 are arranged at a certain spacing. The system anchors 5 are cement mortar anchors with a cement mortar protective layer thickness of not less than 20mm. They are made of ordinary Portland cement or Portland cement with a strength grade of not less than 42.5, medium-fine sand with a maximum particle size of less than 2.0mm and a fineness modulus between 2.4 and 2.8, and generally hot-rolled grade III steel bars with a diameter usually between 25mm and 32mm.

[0040] The system anchor 5 is inserted into the reinforcement hole of the fractured rock slope, with an insertion length of not less than 95% of the design length. The exposed length is generally not less than 100mm. The exposed portion of the system anchor 5 at the connection point with the reinforced concrete frame 1 is firmly welded to the surface reinforcement of the reinforced concrete frame 1, so that the system anchor 5 support and the reinforced concrete frame 1 form an integral load-bearing structure. The axial direction of the reinforcement hole of the system anchor 5 should generally be perpendicular to the excavation outline. The axial direction of the hole of the locally reinforced anchor is generally perpendicular to the possible sliding direction, or at an angle of approximately 45° to the dip of the possible sliding surface.

[0041] The aforementioned anchor bolt 5 support system is used in Class IV and V fractured rock masses. Depending on the specific site conditions, shotcrete or wire mesh shotcrete should be applied first before construction. Anchor bolt grouting involves injecting cement mortar into the borehole. The thickness of the cement mortar protective layer on the bolt body should not be less than 20mm, and the strength of the cement mortar should not be lower than M30. Anchor bolt construction includes measurement and positioning, hole drilling, grouting, and anchor bolt installation. The anchor bolt hole position error should be controlled within 100mm, the allowable deviation of hole depth is ±50mm, the inclination angle deviation is not greater than 2°, and the hole inclination error is not greater than 5% of the hole depth.

[0042] The system anchor bolts 5 further enhance the integrity and stability of the slope rock mass. Through the friction and anchoring force between the system anchor bolts 5 and the rock mass, the deformation and displacement of the rock mass are constrained. Together with the reinforced concrete frame 1, they improve the slope's resistance to sliding and overturning.

[0043] Reinforcing steel protective netting:

[0044] At the bottom of the anchor frame system and on the slope surface of the fractured rock slope, the steel reinforcement protective net 2 is laid. During construction, the steel reinforcement protective net 2 is kept at a distance of 30mm to 50mm from the slope surface.

[0045] The steel reinforcement mesh 2 can be a single-layer or double-layer steel reinforcement mesh, made of smooth steel bars with a yield strength of not less than 300MPa, a diameter of 8mm, and a mesh size of 200mm×200mm. The mesh is constructed by manual binding. At locations with the system anchors 5 and node anchors 6, the steel reinforcement mesh 2 is connected to them using a binding method. At other locations, shallow holes are drilled using a drilling rig, and U-shaped clips are used to fix the steel reinforcement mesh 2, ensuring it does not shake during shotcreting. This allows the steel reinforcement mesh 2 and the anchors to form a stable protective structure, jointly bearing the load of the slope.

[0046] Shotcrete:

[0047] The steel reinforcement mesh 2 is sprayed with the shotcrete 3, which binds the two together through an adhesive process, enhancing the protective strength and stability of the slope. At the same time, the steel reinforcement mesh 2 is protected from corrosion, and together they reinforce and protect the fractured rock slope.

[0048] Shotcrete 3 is composed of cement, aggregate, water, and admixtures, with a thickness of not less than 100 mm and a strength grade of not less than C25. It uses silicate cement or ordinary silicate cement with a strength grade of not less than 42.5. The fine aggregate is hard and durable medium or coarse sand with a fineness modulus preferably greater than 2.5. The coarse aggregate is hard and durable pebbles or crushed stone with a particle size preferably not greater than 12 mm.

[0049] The minimum bond strength between the shotcrete 3 and the rock is 0.2 N / mm². 2 The minimum bond strength between shotcrete and concrete is 0.5 N / mm². 2 The shotcrete is applied using a wet spraying process. The shotcrete is applied using a wet spraying robot. The nozzle of the robot arm is perpendicular to the surface to be sprayed, and the distance should be maintained at 0.6-1.2m. The nozzle moves in a spiral trajectory of D=20-30mm, one turn followed by half a turn.

[0050] The reinforced steel mesh 2 and the shotcrete 3 together constitute the protective layer of the slope. The reinforced steel mesh 2 can distribute the load borne by the slope, prevent local rock mass detachment and collapse, and at the same time provide support for the shotcrete 3, enhancing its bending and shear resistance. Through the bonding effect between the shotcrete 3 and the rock and the reinforced steel mesh 2, the shotcrete 3 seals the slope, preventing erosion and damage to the rock mass by rainwater, weathering and other factors, thus improving the durability and stability of the rock mass.

[0051] Vegetation layer:

[0052] Within each grid of the reinforced concrete frame 1, the vegetation layer 4 is laid. The vegetation layer 4 consists of humus-soil bags, including biodegradable woven bags such as burlap sacks or non-woven bags, filled with humus and grass seeds. The pH of the humus should generally be maintained between 6 and 7.5, and each bag contains 30-80 grams of grass seeds. The humus-soil bags are laid on the slope from bottom to top in a staggered manner, and placed laterally along the slope surface. Adjacent humus-soil bags are closely arranged without gaps, ensuring full contact with the slope surface. This not only beautifies the environment and prevents soil erosion, but also works in conjunction with the entire protective and reinforcement structure to improve the ecological stability of the slope.

[0053] Drainage system:

[0054] The drainage system includes slope drainage holes 7, walkway drainage planting troughs 8, slope bottom drainage ditch 9, and slope top intercepting ditch 10;

[0055] The slope top intercepting ditch 10 is set along the top edge of the slope and is located 3 to 5 meters outside the slope excavation line, for example, 5 meters. Its cross-sectional shape is an inverted trapezoid and it is made of masonry rubble or concrete. Its starting and ending points are connected to the slope bottom drainage ditch 9 to intercept surface water above the slope top, prevent it from flowing into the slope surface, and reduce the water content and hydrostatic pressure of the slope.

[0056] The slope drainage holes 7 are drilled downwards at an angle of not less than 10°, with a diameter of 50mm, a depth of 5m, and a spacing of 3m. A 50mm diameter rigid PVC drainage pipe is installed inside each drainage hole 7 to promptly drain accumulated water from the slope, reducing pore water pressure. The pipe is wrapped with non-woven fabric and extends into the bottom of the drainage hole, with the pipe opening extending beyond the reinforced concrete frame 1 or the shotcrete 3. The slope drainage holes 7 drain water from the slope, and the non-woven fabric-wrapped rigid PVC drainage pipe works in conjunction with the slope protection structure to prevent water flow from eroding and damaging the slope.

[0057] The horse trail drainage planting trough 8 is arranged along the entire horse trail and includes two functional areas: a horse trail drainage ditch and a planting trough. Its starting and ending points are connected to the slope top intercepting ditch 10 to collect and drain the slope surface water.

[0058] The slope bottom drainage ditch 9 is set along the bottom edge of the slope to collect water from the slope top intercepting ditch 10 and the slope surface drainage hole 7. Its cross-sectional shape is rectangular and it is made of concrete. The side near the slope is an L-shaped retaining wall. PVC drainage pipes are pre-embedded inside at a certain spacing to drain the water. The ends of the drainage pipes are wrapped with non-woven fabric, forming a bottom drainage planting trough.

[0059] This constitutes a complete drainage system, preventing water from accumulating at the toe of the slope, and together with the protective and reinforcing structure, ensuring the stability of the slope.

[0060] The following example, using a fractured rock slope in a hydropower project that employs the technical solution of this utility model, is further illustrated with reference to the accompanying drawings:

[0061] like Figures 1-3 As shown, a novel integrated protection and reinforcement structure suitable for fractured rock slopes includes an anchor frame system, system anchors 5, steel reinforcement mesh 2, shotcrete 3, vegetation layer 4, and drainage system.

[0062] The anchor frame system consists of multiple nodal anchors 6 and a reinforced concrete frame 1. The nodal anchors 6 are inclinedly installed within the fractured rock slope, with one end anchored deep into stable bedrock and the other end connected to the reinforced concrete frame 1. The reinforced concrete frame 1 consists of horizontal beams 1-1 and longitudinal beams 1-2. The reinforcing bars of horizontal beams 1-1 and longitudinal beams 1-2 are arranged according to requirements, and the intersections of the reinforcing bars are securely tied with wire. Excavation is carried out using excavators or manual labor according to design requirements, with the trench depth strictly controlled to 10cm, ensuring a flat, firm trench bottom free of loose soil and water, and vertical, neat trench walls. The frame nodes in the reinforced concrete frame 1 serve as key connection points in the entire structural system, such as… Figure 5 and Figure 6As shown, it is divided into edge nodes and middle nodes. The middle nodes are octagonal and the edge nodes are hexagonal. The nodes are firmly connected to the node anchor rods 6. The connection of the steel bars at the nodes is firm and the position is accurate, forming a spatial force system that effectively resists the sliding force and overturning moment of the slope, while providing a support structure for slope protection.

[0063] When pouring concrete, wooden formwork should be used for installation. The surface must be flat, smooth, tightly joined, and free of grout leakage. On-site mixing of concrete should be used, with a mix ratio of not less than C30. During the pouring process, a vibrator should be used to fully compact the concrete. The vibrator should be inserted quickly and withdrawn slowly, penetrating 50-100mm into the lower layer of concrete. Avoid direct contact between the vibrator and the reinforcing steel and formwork to ensure the density and uniformity of the concrete, free from quality defects such as honeycomb, pitting, and voids. Structural joints should be set every 10-15m according to design requirements, and closed-cell foam boards should be used for caulking.

[0064] System anchor bolts 5 are arranged at a certain spacing on the slope surface of fractured rock. The length of the anchor bolt 5 inserted into the hole should not be less than 95% of the design length. For fractured rock masses with poor integrity, high slope height, or steep slope, the length of system anchor bolt 5 must penetrate to a sufficient depth into the fractured rock mass. The exposed length of system anchor bolt 5 should generally not be less than 100mm. The exposed part of system anchor bolt 5 at the connection with reinforced concrete frame 1 must be firmly welded to the surface reinforcement of reinforced concrete frame 1, and the exposed length of system anchor bolt 5 can be appropriately increased. System anchor bolt 5 is a cement mortar anchor bolt, using ordinary Portland cement or Portland cement with a strength grade not lower than 42.5, and medium-fine sand with a maximum particle size of less than 2.0mm and a fineness modulus between 2.4 and 2.8. Larger diameter threaded steel bars are preferred, generally hot-rolled Grade III steel bars with diameters typically between 25mm and 32mm. The axis of the system anchor bolt 5 reinforcement hole should generally be perpendicular to the excavation outline. For locally reinforced system anchor bolts 5, the hole axis should generally be perpendicular to the possible sliding direction, or at an angle of approximately 45° to the possible sliding surface. When system anchor bolt 5 support is applied in Class IV and V fractured rock masses, concrete 3 should be sprayed first, or a steel reinforcement mesh 2 should be installed before spraying concrete 3, depending on the specific site conditions, before proceeding with construction. Grouting of system anchor bolt 5 involves injecting cement mortar into the drilled holes. The thickness of the cement mortar protective layer on the bolt body should not be less than 20mm, and the cement mortar strength should not be lower than M30. The construction of system anchor bolt 5 includes measurement and positioning, hole drilling, grouting, and anchor bolt installation. First, a total station is used to measure and mark the spacing between system anchor bolts 5, and the points are marked with paint. System anchor bolts 5 are drilled using a down-the-hole drill. After drilling, an anchor bolt hole acceptance procedure is performed promptly to avoid hole collapse. After drilling is completed, the anchor bolt holes should be inspected immediately using tools such as inclinometers and steel rulers. The anchor bolt hole position error should be controlled within 100mm, the allowable deviation in hole depth is ±50mm, the inclination angle deviation is not greater than 2°, and the hole inclination error is not greater than 5% of the hole depth. If problems such as hole wall collapse or hole diameter not meeting requirements are found, measures such as re-drilling and installing casing should be taken in a timely manner to ensure that the quality of the anchor bolt holes meets the installation requirements. Mortar anchor bolts should be installed using the procedure of "grouting first, then inserting the bolt". First, insert the grouting pipe to the bottom of the hole, then withdraw it 50-100mm, and start grouting. The grouting pipe should be slowly and evenly pulled out as the grout is injected. When the grout fills 2 / 3 of the anchor bolt hole, grouting should be stopped, and anchor bolt installation should proceed. After the anchor bolt holes are grouted, the anchor bolts are installed using a combination of manual labor and machinery. After the anchor bolts are installed, grout is added to the anchor bolt holes at the opening. When the grout overflows outside the holes, the grouting is stopped to ensure a firm bond between the system anchor bolts 5 and the rock mass, forming an effective anchoring force, improving the reinforcement effect of the system anchor bolts on the slope, and enhancing the stability of the slope.

[0065] The reinforcing mesh 2 is laid on the slope surface of the fractured rock mass, located at the bottom of the reinforced concrete frame 1, and maintains a certain distance from the slope surface, generally 30mm to 50mm. Spacing can be controlled using spacers or positioning bars so that the shotcrete 3 can fully wrap the reinforcing bars of the reinforcing mesh 2. The material of the reinforcing mesh 2 is smooth steel bar with a yield strength of not less than 300MPa, a diameter of 8mm, and a mesh size of 200mm×200mm. The reinforcing mesh 2 is constructed by manually binding the mesh. At the locations with system anchors 5 and node anchors 6, the reinforcing mesh 2 is connected to the system anchors 5 and node anchors 6 by binding. At other locations, shallow holes are drilled using a drilling rig, and the reinforcing mesh 2 is fixed with "U"-shaped clips to ensure that the reinforcing mesh 2 is firmly bound and that the reinforcing bars do not shake when the shotcrete 3 is applied.

[0066] Shotcrete 3 is sprayed onto the reinforced protective mesh 2. Shotcrete 3 is composed of cement, aggregate, water, and admixtures, with a thickness of 100mm and a strength grade of not less than C25. Ordinary Portland cement is used for shotcrete 3, with a strength grade of not less than 42.5. The fine aggregate in shotcrete 3 should be hard and durable medium or coarse sand with a fineness modulus greater than 2.5, and the coarse aggregate should be hard and durable pebbles or crushed stone with a particle size not greater than 12mm. The minimum bond strength between shotcrete 3 and rock is 0.2N / mm2, and the minimum bond strength between shotcrete 3 and concrete is 0.5N / mm2. Shotcrete 3 is applied using a wet spraying process, with a wet spraying robot used for construction. The nozzle of the robot arm is perpendicular to the sprayed surface, and the distance should be maintained at 0.6 to 1.2m. The nozzle moves in a spiral trajectory of D = 20 to 30mm, alternating between one and half turns.

[0067] The fourth vegetation layer mainly consists of humus-soil bags. Humus and grass seeds are thoroughly mixed in a certain proportion and then packed into biodegradable woven bags (such as burlap sacks, non-woven bags, etc.). The amount of grass seeds in each bag is strictly controlled between 30 and 80 grams. The pH of the humus soil is maintained between 6 and 7.5 to ensure that the grass seeds can germinate and grow smoothly in a suitable soil environment, providing basic conditions for the ecological restoration of the slope, promoting the recovery and growth of vegetation, and improving the ecological environment of the slope.

[0068] The prepared humus-soil bags are transported to the slope and laid out from bottom to top in a staggered manner within a reinforced concrete frame 1. They are placed horizontally along the slope, with adjacent bags tightly packed together without gaps, ensuring full contact with the slope surface. The bags can be laid and adjusted manually or with simple tools to ensure the quality and stability of the bag laying, promote the germination of grass seeds and the growth of vegetation, and form an effective vegetation cover layer. This not only beautifies the environment but also further enhances the stability of the slope through the soil stabilization effect of the root system, achieving an organic combination of slope protection and ecological restoration, and realizing the goal of ecological and environmental protection.

[0069] The drainage system includes a slope top intercepting ditch 10, slope surface drainage holes 7, walkway drainage planting troughs 8, and slope bottom drainage ditch 9; the slope top intercepting ditch 10, such as... Figure 4 As shown, drainage holes 7 are installed along the top edge of the slope, located 5m outside the excavation line. Their cross-sectional shape is an inverted trapezoid, constructed of grouted rubble or concrete, to intercept surface water above the slope top and prevent it from flowing into the slope surface. Drainage holes 7 are drilled downwards at an angle of 10°, with a diameter of 50mm and a depth of 5m. The spacing between holes is 3m. A 50mm diameter rigid PVC drainage pipe, covered with non-woven fabric, is installed inside each drainage hole 7, extending into the bottom of the hole and protruding from the concrete of the grid beam 1 or... In addition to the shotcrete 3, the slope drainage holes 7 are used to drain accumulated water from the slope in a timely manner, reducing the pore water pressure of the slope. The walkway drainage planting trough 8 is arranged along the entire walkway and includes two functional areas: a walkway drainage ditch and a planting trough, used to collect accumulated water on the slope. The bottom drainage ditch 9 is set along the bottom edge of the slope, with a rectangular cross-section, made of cast concrete, and an "L"-shaped retaining wall near the slope side. PVC drainage pipes are pre-embedded inside at certain intervals, and the ends of the drainage pipes are covered with non-woven fabric, forming the bottom drainage planting trough. The bottom drainage ditch 9 collects water from the top intercepting ditch and the slope drainage holes, and drains the water through the pre-embedded PVC drainage pipes. This complete drainage system prevents water from accumulating at the slope toe and, together with the protective reinforcement structure, ensures the stability of the slope.

[0070] This utility model discloses a novel integrated protection and reinforcement structure suitable for fractured rock slopes, which has the following advantages:

[0071] (1) Structural stability is significantly improved:

[0072] The anchor frame system, through the designed octagonal central node and hexagonal side node, is firmly connected to the node anchors (anchor bar bundles or anchor cables), forming an efficient spatial force-bearing system that can more effectively resist the slope's sliding force and overturning moment.

[0073] Compared to traditional node designs, this unique polygonal node structure increases the connection stiffness and stability of the nodes, making the force transmission in the anchor frame system more uniform and reasonable. This greatly enhances the constraint capacity of the entire protection and reinforcement structure on the deformation of the fractured rock slope, ensuring that the slope remains stable under complex geological conditions and external loads.

[0074] The system of anchor bolts is rationally arranged and its parameters optimized according to the characteristics of the fractured rock mass. It penetrates deep enough into the fractured rock mass and is reliably connected to the anchor bolt frame system, which further enhances the overall stability of the slope and provides a strong guarantee for the long-term stability of the slope.

[0075] (2) Enhanced slope protection effect:

[0076] The reinforced mesh structure not only enhances the slope's resistance to impact, but also effectively prevents the weathering and erosion of the slope's rock mass. It can effectively resist the erosion of the slope by natural factors such as rainwater erosion and weathering, protect the stability and durability of the slope, and provide a stable foundation for the growth of vegetation on the slope.

[0077] (3) It combines ecological restoration and environmental friendliness:

[0078] The vegetation layer uses humus-covered grass bags. The humus provides abundant nutrients and a suitable pH level, which is conducive to the germination and growth of grass seeds. The resulting vegetation cover not only beautifies the environment but also further enhances slope stability through root stabilization. The biodegradable nature of the grass bags avoids secondary pollution, meeting ecological and environmental protection requirements. The bottom-up, staggered stacking method ensures a close fit between the grass bags and the slope surface, improving vegetation survival and coverage, and promoting the restoration and balance of the slope ecosystem.

[0079] (4) The drainage system is highly efficient and reliable:

[0080] The drainage system, consisting of a top intercepting ditch, slope drainage holes, a walkway drainage planting trough, and a bottom drainage ditch, can comprehensively and effectively remove surface water and groundwater within the slope area. The top intercepting ditch is strategically positioned to intercept surface water above the slope, preventing direct erosion of the slope surface. The slope drainage holes, with their specific elevation angle, diameter, depth, and spacing design, along with the internal drainage pipes and non-woven fabric, promptly drain accumulated water from the slope, reducing pore water pressure and minimizing the adverse effects of water on rock stability. The bottom drainage ditch's rectangular cross-section, "L"-shaped retaining wall, and pre-embedded drainage pipe design ensure smooth and stable drainage. The resulting drainage planting trough also provides ecological benefits, further optimizing the overall drainage and ecological environment of the slope and effectively preventing slope instability caused by water accumulation.

[0081] In summary, the integrated protection and reinforcement structure of this utility model can effectively address the instability problem of fractured rock slopes under weathering and unloading. It has advantages such as high stability, strong durability, good adaptability, and environmental friendliness, and has broad application prospects in the field of slope protection and reinforcement in hydropower projects.

[0082] The embodiments described above are only used to illustrate the technical ideas and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. The patent scope of this utility model should not be limited by these embodiments. That is, any equivalent changes or modifications made to the spirit disclosed in this utility model still fall within the patent scope of this utility model.

Claims

1. A novel integrated protection and reinforcement structure suitable for fractured rock slopes, characterized in that, include: Anchor frame system, system anchors (5), steel reinforcement mesh (2), shotcrete (3) and vegetation layer (4); The anchor frame system includes a reinforced concrete frame (1) and node anchors (6); the reinforced concrete frame (1) is a grid-like frame structure, including multiple grids, fixed to the slope surface of the fractured rock slope; at each frame node position of the reinforced concrete frame (1), the node anchors (6) are set, the node anchors (6) are inclinedly set in the fractured rock slope, one end is anchored deep in the stable bedrock, and the other end is connected to the reinforced concrete frame (1); on the slope surface of the fractured rock slope, the system anchors (5) are arranged at a certain spacing; at the bottom of the anchor frame system and on the slope surface of the fractured rock slope, the steel reinforcement protective net (2) is laid, and the steel reinforcement protective net (2) is sprayed with the shotcrete (3); in each grid of the reinforced concrete frame (1), the vegetation layer (4) is laid.

2. The novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The reinforced concrete frame (1) includes a crossbeam (1-1) and a longitudinal beam (1-2); the bottom of the reinforced concrete frame (1) is embedded into the slope of the broken rock slope to a depth of 10cm.

3. The novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The frame nodes of the reinforced concrete frame (1) include edge nodes and intermediate nodes; the edge nodes are hexagonal; and the intermediate nodes are octagonal.

4. The novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The node anchor (6) is a cement mortar anchor, anchor bar bundle, or anchor cable.

5. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The system anchor (5) is a cement mortar anchor. The system anchor (5) is inserted into the reinforcement hole of the broken rock slope, with an insertion length of not less than 95% of the design length and an exposed length of not less than 100mm. The exposed part of the system anchor (5) at the connection with the reinforced concrete frame (1) is firmly welded to the surface reinforcement of the reinforced concrete frame (1). The axial direction of the reinforcement hole of the system anchor (5) is perpendicular to the excavation outline.

6. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 5, characterized in that, The thickness of the cement mortar protective layer of the anchor rod (5) of the system is not less than 20mm.

7. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The steel reinforcement protective net (2) is a single-layer or double-layer steel reinforcement net. It uses smooth steel bars with a yield strength of not less than 300MPa, a diameter of 8mm, and a mesh size of 200mm×200mm. The net is constructed by manually binding the mesh. At the locations where the system anchor rod (5) and the node anchor rod (6) are located, the steel reinforcement protective net (2) is connected to the system anchor rod (5) and the node anchor rod (6) by binding. Other locations are fixed with U-shaped clips.

8. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The thickness of the sprayed concrete (3) shall not be less than 100 mm.

9. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, The vegetation layer (4) is a humus bag, which includes a biodegradable woven bag and humus and grass seeds filled inside the woven bag; each bag contains 30-80 grams of grass seeds. The humus bags are laid on the slope from bottom to top in a staggered manner and are placed horizontally along the slope surface, with adjacent humus bags arranged closely together.

10. A novel integrated protection and reinforcement structure for fractured rock slopes according to claim 1, characterized in that, It also includes a drainage system; the drainage system includes slope drainage holes (7), walkway drainage planting troughs (8), slope bottom drainage ditch (9) and slope top intercepting ditch (10); The slope top intercepting ditch (10) is set along the top edge of the slope and located at a distance of not less than 5m outside the slope excavation line. Its cross-sectional shape is an inverted trapezoid and it is made of mortar-grouted rubble or concrete. The slope drainage hole (7) is drilled downward along the slope with an elevation angle of not less than 10°, a diameter of 50mm, a hole depth of 5m, and a row spacing of 3m. A 50mm diameter PVC rigid drainage pipe is installed in the slope drainage hole (7), wrapped with non-woven fabric, and extends into the bottom of the drainage hole. The pipe opening extends out of the reinforced concrete frame (1) or the shotcrete (3). The horse trail drainage planting trough (8) is arranged along the entire horse trail and includes two functional areas: a horse trail drainage ditch and a planting trough. Its starting and ending points are connected to the slope top intercepting ditch (10). The drainage ditch (9) at the bottom of the slope is set along the bottom edge of the slope. Its cross-sectional shape is rectangular and it is made of concrete. The side near the slope is an L-shaped retaining wall. PVC drainage pipes are pre-embedded inside at a certain spacing. The ends of the drainage pipes are wrapped with non-woven fabric, forming a bottom drainage planting trough.

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