Basalt fiber anchor double slurry bag prestressed structure and its construction method

Abstract

The present invention relates to a basalt fiber anchor rod double grouting bag prestressed structure and a construction method thereof. By setting up a steel casing connector and a filling layer, the shear resistance of the basalt fiber anchor rod is effectively improved, so that it can adapt to the needs of pre-tensioning construction, thereby broadening the application range of the basalt fiber anchor rod in slope anchoring projects. The setting of the double grouting bag (a first grouting bag component and a second grouting bag component) makes the grouting process more accurate and efficient. By dividing the bottom hole grouting section, the free section and the end grouting section, the segmented control of the grouting process is realized, which effectively prevents the leakage of slurry and ensures the grouting effect. This method greatly simplifies the construction process and improves the construction efficiency. At the same time, the pre-tensioned deformation composite structure effectively solves the problems of basalt fiber anchor rods being susceptible to shear damage, low pre-tensioning force value, insufficient durability, and easy relaxation of prestress during pre-tensioning, providing a new solution for slope prestressed anchoring projects.

Description

Technical Field

[0001] The present invention relates to the technical field of slope structures, and more particularly to a basalt fiber anchor rod double-stop slurry bag prestressed structure and a construction method thereof. Background Art

[0002] In geotechnical engineering, slope anchoring technology has long been considered a crucial tool for maintaining the safety and stability of roadbed slopes. Traditional slope anchoring methods primarily rely on steel bars as anchor rods. However, while this method offers engineering benefits, it also causes significant environmental pollution. With growing environmental awareness, people are seeking more environmentally friendly and efficient anchoring materials and technologies.

[0003] Basalt fiber rebar, a new environmentally friendly material, is gradually being used in geotechnical engineering due to its high strength, resistance to acid and alkali corrosion, and low density. However, in slope prestressed anchoring projects, basalt fiber anchor prestressing components are prone to shear failure, low prestressing force, insufficient durability, and easy relaxation of prestressing force, which prevents basalt fiber anchors from fully realizing their potential in prestressed anchoring projects.

[0004] Currently, prestressing methods commonly used in slope anchoring projects primarily include single-port anchor sleeve clips and multi-hole anchor cable clamps. These methods are widely used with materials with strong shear resistance, such as rebar and stranded steel, but are less suitable for materials with weaker shear resistance, such as basalt fiber rebar. Traditional prestressing components are prone to shear failure of basalt fiber rebar. While they can generate temporary prestressing force, the low prestressing force and the tendency for prestressing to relax are significant issues.

[0005] Therefore, developing a pre-stressing construction process suitable for basalt fiber anchor rods can effectively solve the problems of basalt fiber anchor rods being susceptible to shear damage, low pre-stressing force, insufficient durability, and easy relaxation of prestress during the pre-stressing process. This is of great significance for promoting the application of this environmentally friendly material in slope prestressed anchoring projects. Summary of the Invention

[0006] In view of the above problems, the purpose of the present invention is to provide a basalt fiber anchor rod double slurry bag prestressed structure and its construction method, so as to solve the problems of easy shear failure, low prestressing force, insufficient durability, easy relaxation of prestressing in the existing pre-stressing technology, and the lack of grouting hole construction technology suitable for basalt fiber anchor rods with weak shear resistance.

[0007] The present invention provides a basalt fiber anchor rod double-stop slurry bag prestressed structure, comprising a pre-tensioned component and a pre-tensioned deformation composite structure;

[0008] The pre-tensioned component includes: basalt fiber anchor rod, filling layer, steel casing connector, first prefabricated nut, second prefabricated nut, anchor tray and sealing and centering dual-purpose rubber ring, wherein,

[0009] The steel sleeve connector is provided with an inner cavity, the basalt fiber anchor rod is sleeved in the inner cavity of the steel sleeve connector and is connected to the steel sleeve connector through the filling layer; the steel sleeve connector is also provided with an external thread, and the external thread is adapted to a first prefabricated nut and a second prefabricated nut respectively; the first prefabricated nut is connected to the external thread of the steel sleeve connector by counter-rotation to form a first end, and the second prefabricated nut is connected to the external thread of the steel sleeve connector by forward rotation to form a second end; the anchor tray is connected to the second prefabricated nut and faces away from the first end; the sealing and centering dual-purpose rubber ring is provided in the gap between the basalt fiber anchor rod and the steel sleeve connector;

[0010] The pre-tensioned deformation composite structure includes: a number of support rods arranged parallel to the slope hole axis, a bottom hole fixing piece, an end fixing piece, a first grouting component, a bottom hole grouting pipe, a deep grouting pipe, a shallow grouting pipe, a second grouting component, an end grouting pipe and an exhaust pipe. The space between the bottom hole fixing piece and the second grouting component forms a bottom hole grouting section, the space between the second grouting component and the first grouting component forms a free section, and the space between the first grouting component and the end fixing piece forms an end grouting section, wherein,

[0011] One end of the basalt fiber anchor rod, bottom hole grouting pipe and several support rods are all fixed to the bottom hole fixing piece, the first grouting part and the second grouting part are both preset with a through hole and a semi-through hole, the other end of the bottom hole grouting pipe is fixed to the semi-through hole of the second grouting part, the deep grouting pipe passes through the end fixing piece and the through hole of the first grouting part and is fixed to the semi-through hole of the second grouting part, the shallow grouting pipe passes through the end fixing piece and is fixed to the semi-through hole of the first grouting part, the end grouting pipe passes through the end fixing piece and its slurry outlet is located between the first grouting part and the end fixing piece, the exhaust pipe passes through the end fixing piece, the through hole of the second grouting part and the through hole of the first grouting part, the support rod passes through the end fixing piece, the through hole of the second grouting part and the through hole of the first grouting part and the bottom hole fixing piece.

[0012] Compared to existing technologies, this technical solution offers the following advantages: The provision of a rebar sleeve connector and a filling layer effectively enhances the shear resistance of basalt fiber anchors, making them suitable for pre-tensioning applications and broadening their application in slope anchoring projects. The dual grouting sacs (a primary grouting component and a secondary grouting component) ensure more precise and efficient grouting. The division of the grouting process into bottom-hole grouting, free-hole, and end-hole grouting sections enables segmented control of the grouting process, effectively preventing grout leakage and ensuring effective grouting. Replacing traditional rebar anchors with basalt fiber anchors significantly reduces environmental pollution, meeting the requirements of green building and sustainable development. The provision of multiple support rods not only provides additional support for the anchor rods but also enhances the overall stability of the structure. The support rods, which run through all components, form a unified structure, ensuring the anchor rod remains stable even under external forces. The modular design of the structure, with components connected via simple means such as threaded connections, significantly simplifies the construction process and improves efficiency. At the same time, the design of the pre-tensioned deformation composite structure also makes the pre-tensioning process simpler and easier. In summary, the basalt fiber anchor double-stop slurry bag prestressed structure shows significant advantages in terms of environmental protection, shear resistance, grouting effect, stability, construction simplicity, and applicability, providing a new solution for slope anchoring projects.

[0013] It should be noted that the designations of "first prefabricated nut" and "second prefabricated nut" in the present invention are merely for the purpose of distinguishing the two nuts used. In actual operation, the following four situations may occur: 1) the "first prefabricated nut" is a prefabricated left-handed nut, and the "second prefabricated nut" is a prefabricated right-handed nut; 2) both the "first prefabricated nut" and the "second prefabricated nut" are prefabricated left-handed nuts; 3) both the "first prefabricated nut" and the "second prefabricated nut" are prefabricated right-handed nuts; 4) the "first prefabricated nut" is a prefabricated right-handed nut, and the "second prefabricated nut" is a prefabricated left-handed nut. "Right-handed" refers to screwing the nut clockwise along the outer thread of the steel sleeve connector, while "left-handed" refers to screwing the nut counterclockwise along the outer thread of the steel sleeve connector.

[0014] In a preferred embodiment of the present application, the support rods are steel, with four or more rods. As a high-strength material, steel can significantly improve the support rods' load-bearing capacity and stability. Increasing the number of support rods to four or more in a slope anchor structure creates a more stable support system that can better withstand the various forces and pressures generated by the anchor rods and grouting, ensuring the stability of the entire structure when subjected to external forces. Multiple support rods support and secure the anchor rods from multiple directions, improving the overall stability of the structure. This helps ensure that the slope anchor structure remains stable and reliable even under complex geological conditions and external environmental influences, effectively preventing structural deformation or damage. Steel support rods have excellent shear resistance, which further enhances the shear resistance of basalt fiber anchor rods. During the pre-tensioning process, steel support rods effectively disperse and transfer stress, preventing anchor rod failure under shear forces. By adjusting the number and layout of support rods, the specific needs of different projects can be met. For example, in areas with poor geological conditions or complex stress conditions, the number and density of support rods can be increased to improve the structure's load-bearing capacity and stability. This flexibility and adaptability give the structure a wider range of application prospects.

[0015] As a preferred embodiment of the present application, it further comprises a binding ring surrounding and binding the outer periphery of the support rod. By providing the binding ring, the relative position of the longitudinal steel frame is easily positioned and a support surface is formed between the longitudinal steel frame and the grouting hole.

[0016] As a preferred embodiment of the present application, a minimum of 1 meter is reserved for the bottom hole grouting section and the end grouting section along the slope borehole extension direction, with the remaining length being the length of the free section. The bottom hole grouting section and the end grouting section are critical areas for grouting, and reserving sufficient length ensures that the grouting material is fully filled and solidified, forming a stable anchoring layer. The 1-meter length provides the grouting material with ample space and time to diffuse and solidify, thereby ensuring effective grouting. Different geological conditions have different requirements for grouting effectiveness. Reserving sufficient grouting section length can adapt to various geological conditions and ensure the desired anchoring effect is achieved in various situations. While ensuring effective grouting, reserving an appropriate grouting section length can avoid waste caused by excessive grouting and thus control costs. A length of 1 meter is a reasonable value verified by actual engineering, ensuring both effective grouting and cost control. By reserving sufficient length for the bottom hole grouting section and the end grouting section, the grouting material is fully filled and solidified, forming a stable anchoring layer, which helps to strengthen the bond between the anchor rod and the rock and soil, improving the anchoring effect. After the grouting material solidifies in the bottom and end grouting sections, it forms a single entity with the rock and soil, improving the stability of the entire structure. This not only helps resist external loads but also effectively prevents geological disasters such as slope sliding. By reserving appropriate grouting section lengths, it is possible to ensure grouting effectiveness while controlling costs, helping to reduce project costs and improve economic benefits, providing a more reliable and efficient solution for slope anchoring projects.

[0017] As a preferred embodiment of the present application, the inner diameter of the rebar sleeve connector is 2mm larger than the diameter of the basalt fiber anchor. This configuration ensures a 1mm gap between the rebar sleeve connector and the basalt fiber anchor. This gap thickness is suitable for bonding the basalt fiber anchor with other materials, maximizing the tensile properties of the basalt fiber anchor and preventing shear failure, thereby preserving the overall tensile strength of the basalt fiber anchor.

[0018] As a preferred embodiment of the present application, the sealing and centering dual-purpose rubber ring includes a sealing and centering dual-purpose upper rubber ring and a sealing and centering dual-purpose lower rubber ring, wherein the sealing and centering dual-purpose lower rubber ring is arranged at the upper end of the reaction base of the preset pressure-adding equipment and in the gap between the basalt fiber anchor rod and the steel casing connector. Providing a sealing and centering dual-purpose rubber ring in the gap between the basalt fiber anchor rod and the steel casing connector can ensure that during the pre-tensioning process, the gap will not be invaded by grouting materials or external impurities, thereby improving the sealing performance of the structure. The sealing and centering dual-purpose rubber ring not only has a sealing function, but also plays a centering role. During the pre-tensioning process, the sealing and centering dual-purpose rubber ring can ensure the centering between the basalt fiber anchor rod and the steel casing connector, preventing stress concentration or structural damage caused by offset. Positioning the lower end of the dual-purpose sealing and centering rubber ring at the upper end of the pre-set pressure equipment reaction base ensures that the dual-purpose sealing and centering rubber ring can effectively withstand the reaction force during the pressurization process and prevent the increase in gaps or leakage caused by pressurization. In short, this arrangement improves the structure's sealing performance, enhances the centering function, adapts to the pressure equipment, and improves construction efficiency, providing a more reliable and efficient solution for slope anchoring projects.

[0019] As a preferred embodiment of the present application, the first grouting stop component and the second grouting stop component are both flexible accommodating chambers with preset through holes and semi-through holes. The design of the flexible accommodating chamber enables the first grouting stop component and the second grouting stop component to adapt to changes in grouting pressure during the grouting process. As the grouting proceeds, the grouting pressure will gradually increase, and the flexible accommodating chamber can expand or contract accordingly to ensure the smooth progress of the grouting process. By pre-setting through holes and semi-through holes, the flexible accommodating chamber can be well connected with components such as grouting pipes and anchor rods as the grouting proceeds. Therefore, the first grouting stop component and the second grouting stop component are designed as flexible accommodating chambers with preset through holes and semi-through holes, which can adapt to changes in grouting pressure, prevent slurry leakage, simplify the installation process, and improve grouting efficiency, structural stability, reduce project costs and improve project quality.

[0020] As a preferred embodiment of the present application, the pre-tensioned deformation composite structure further includes an exhaust pipe, one end of which is disposed in the bottom hole grouting section. The exhaust pipe facilitates the exhaust of air during the grouting process of the bottom hole grouting section.

[0021] To achieve the above-mentioned purpose, in a second aspect, the inventors also provide a construction method of a basalt fiber anchor rod double-stop slurry bag prestressed structure according to the first aspect of the present invention, comprising the following steps:

[0022] S1: Drilling and cleaning the hole, placing the basalt fiber anchor and the pre-tensioned deformation composite structure into the hole, and the bottom hole grouting pipe is located on the side close to the bottom of the hole;

[0023] S2: placing the slope reaction member and inserting it into the anchor tray, wherein the anchor tray is connected to the second prefabricated nut and faces the bottom of the hole;

[0024] S3: Sleeve the steel bar sleeve connector on the outside of the basalt fiber anchor, place the sealing and centering dual-purpose lower end rubber ring at a first preset position of the basalt fiber anchor, sleeve the steel bar sleeve connector on the basalt fiber anchor, and connect it to the sealing and centering dual-purpose lower end rubber ring, the sealing and centering dual-purpose lower end rubber ring is used to seal the gap formed by the steel bar sleeve connector and the basalt fiber;

[0025] S4: Injecting adhesive material into the gap between the steel casing connector and the basalt fiber anchor rod, so that the adhesive material fills the entire gap in the casing; placing the upper end rubber ring for sealing and centering at the second preset position of the basalt fiber anchor rod;

[0026] S5: Sleeve the reaction base of the pressurizing device on the basalt fiber anchor and place it in the first preset position, screw the first prefabricated nut onto the outer wall of the steel bar sleeve connector and connect it to the pressure-bearing surface of the pressurizing device;

[0027] S6: Grouting at the bottom grouting section, grouting into the deep grouting pipe so that the second grouting stopper blocks the orifice at that position, and the overflowing slurry flows through the bottom grouting pipe to the bottom grouting section. When slurry flows out of the exhaust pipe, grouting is stopped;

[0028] S7: Start prestressing. When the grouting section at the bottom of the hole reaches the designed strength, start the pressurizing device to push the second prefabricated nut. After the designed prestress value is reached, the pressurizing device maintains a steady pressure state to continuously tension the basalt fiber anchor.

[0029] S8: Grouting at the end grouting section: grouting into the shallow grouting pipe until the pressure value displayed by the pressure pump changes, then grouting into the end grouting pipe until the grouting overflows from the orifice, and then stopping grouting;

[0030] S9: Let it stand until the end grouting section reaches the designed strength, relieve the pressure on the pressurizing device, remove the pressurizing device, and tighten the second prefabricated nut to engage it with the anchor tray.

[0031] Different from the existing technology, the above technical solution has the following advantages: the design of the double slurry bag can ensure that the grouting material forms a stable anchoring layer at the predetermined position, thereby improving the bonding force between the anchor rod and the rock and soil, and the stability and durability of the entire structure. By tensioning the anchor rod with a pressure-applying device and maintaining a stable pressure state, the prestress value of the anchor rod can be accurately controlled to meet the design requirements. This construction method can adapt to different geological conditions and engineering requirements, and achieve the expected anchoring effect by adjusting parameters such as grouting volume and grouting pressure. Through precise construction steps and effective grouting measures, a close connection between the anchor rod and the rock and soil can be ensured, and the anchoring effect and the bearing capacity of the structure can be improved. This construction method has clear steps and is easy to operate, which can improve construction efficiency and shorten construction period. By optimizing the construction process and accurately controlling the use of materials, the project cost can be reduced and the economic benefits can be improved. During the construction process, strict operating procedures and effective safety measures can be used to ensure construction safety and reduce the risk of accidents. In summary, the construction method of the basalt fiber anchor double-stop slurry bag prestressed structure can ensure construction quality, improve structural stability, high construction efficiency, low cost and high safety, and provide a reliable and efficient solution for slope anchoring projects.

[0032] As a preferred embodiment of the present application, the steel sleeve connector, the first prefabricated nut and the second prefabricated nut are all made of No. 45 steel. No. 45 steel is a high-quality carbon structural steel with high strength and hardness, which enables the steel sleeve connector, the first prefabricated nut and the second prefabricated nut to maintain sufficient strength and stability when subjected to tension and grouting pressure, thereby ensuring the reliability and durability of the entire prestressed structure. At the same time, its good welding performance also makes the connection more firm and reliable. No. 45 steel has moderate mechanical properties and can maintain stable performance under various environmental conditions. Whether in cold or hot climates, or in humid or dry environments, this steel can maintain its strength and toughness, ensuring the long-term stable operation of the prestressed structure. The use of No. 45 steel can reduce pollution to the environment. Compared with some non-metallic materials, steel does not produce harmful substances during use and is easier to recycle and reuse after disposal. Therefore, the steel sleeve connector, the first prefabricated nut and the second prefabricated nut are made of 45 steel, which can improve the strength, durability and reliability of the prestressed structure while reducing manufacturing costs and environmental pollution.

[0033] As a more preferred embodiment, 6-8 support rods are used to form a pre-tensioned deformation composite structure.

[0034] The above-mentioned records related to the content of the invention are only an overview of the technical solution of this application. In order to enable ordinary technicians in this field to understand the technical solution of this application more clearly, and then implement it according to the text of the specification and the contents recorded in the drawings, and to make the above-mentioned purposes and other purposes, features and advantages of this application easier to understand, the following is an explanation in combination with the specific implementation methods and drawings of this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 The top view of the basalt fiber anchor pre-tensioned component is used as a whole;

[0037] Figure 2 Bottom view of the basalt fiber anchor pre-tensioned member as a whole;

[0038] Figure 3 This is the exploded accessories diagram of the basalt fiber anchor pre-tensioned component;

[0039] Figure 4 This is the composite structure diagram of basalt fiber anchor pre-tensioning deformation;

[0040] Figure 5 This is a schematic diagram of the on-site construction of the basalt fiber anchor double-stop slurry bag prestressed structure;

[0041] The reference numerals in the above drawings are described as follows:

[0042] 1. Basalt fiber anchor rod; 2. Filling layer; 3. First prefabricated nut - pressure-bearing nut; 4. Rebar casing connector - threaded steel casing; 5. Second prefabricated nut - fiberglass reinforced plastic nut; 6. Anchor tray; 7. Sealing and centering dual-purpose upper rubber ring; 8. Sealing and centering dual-purpose lower rubber ring;

[0043] 10. Pressurizing equipment; 11. Reaction base of pressurizing equipment; 12. Slope reaction member; 13. Support rod - longitudinal steel frame; 14. Steel wire binding ring; 15. Grouting pipe at bottom of hole; 16. Deep grouting pipe; 17. Shallow grouting pipe; 18. End grouting pipe; 19. Exhaust pipe; 20. Grouting section at bottom of hole; 21. Free section; 22. End grouting section; 23. Second grouting stop component - deep grouting bag; 24. First grouting stop component - shallow grouting bag; 25. Hole bottom fixing piece; 26. End fixing piece. DETAILED DESCRIPTION

[0044] In order to explain in detail the possible application scenarios, technical principles, specific solutions that can be implemented, and the purpose and effects of this application, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of this application and are therefore only examples and are not intended to limit the scope of protection of this application.

[0045] References to "embodiments" herein mean that the specific features, structures, or characteristics described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the word "embodiment" in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or relevance to other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the various technical features mentioned in the embodiments can be combined in any manner to form a corresponding implementable technical solution.

[0046] Unless otherwise defined, the technical terms used herein have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms herein is only for describing specific embodiments and is not intended to limit this application.

[0047] In the description of this application, the term "and / or" is used to describe a logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and both A and B exist. In addition, the character " / " in this document generally indicates that the objects before and after are in a logical "or" relationship.

[0048] In this application, terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual quantity, priority or sequence relationship between these entities or operations.

[0049] Without further limitations, in this application, the words "include", "comprise", "have" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those defined elements, but also other elements not explicitly listed, or elements inherent to such process, method or product.

[0050] Consistent with the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceed" are understood to exclude the number itself; expressions such as "above," "below," and "within" are understood to include the number itself. Furthermore, in the description of the embodiments of this application, "multiple" means two or more (including two), and similar expressions related to "multiple," such as "multiple groups" and "multiple times," are also understood in this manner, unless otherwise specifically defined.

[0051] In the description of the embodiments of the present application, the space-related expressions used, such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or position relationship based on the orientation or position relationship shown in the specific embodiments or drawings, and are only for the convenience of describing the specific embodiments of the present application or facilitating the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, it should not be understood as a limitation on the embodiments of the present application.

[0052] Unless otherwise expressly specified or limited, in the description of the embodiments of the present application, the terms "installed", "connected", "connected", "fixed", "set", etc. used should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integrated setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art of the present application, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0053] Basalt fiber anchor rod is a new type of composite anchor rod made of basalt fiber, resin, curing agent, etc. through pultrusion, winding, high-temperature curing and molding processes. It has the characteristics of high tensile strength, easy cutting, no damage to the pick, no sparks, safe coal mining efficiency, light weight, high corrosion resistance, flame retardant, and anti-static properties. It is a type of fiber composite bar. Traditional slope anchoring mostly uses steel bars as anchor rods, which causes considerable pollution to the environment. The commonly used passive pre-tensioning construction method is generally applicable to steel bars and steel strands, and the pre-tensioned material needs to have a certain strength of shear resistance. Due to the weak shear resistance of basalt fiber anchor rods, it is easy to cause shear damage to basalt fiber anchor rods, and it is impossible to effectively pre-tension basalt fiber anchor rods, which greatly limits the application of environmentally friendly materials such as fiber composite bars. Based on this, the present invention intends to provide a basalt fiber anchor rod double-stop slurry bag prestressed structure and its construction method, so as to provide a solution for active pre-tensioning of basalt fiber anchor rods, break through the limitations of passive anchoring of basalt fiber anchor rods, and enrich the use scenarios of active pre-tensioning, so as to achieve a larger tonnage tensile effect, broaden the application scope of basalt fiber anchor rods and promote the popularization of environmentally friendly materials in construction and geotechnical engineering.

[0054] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0055] See also Figure 1-5 , a basalt fiber anchor double stop slurry bag prestressed structure, including pre-tensioned components ( Figure 1-Figure 3 ) and pre-tensioned deformation composite structure ( Figure 4 The pre-tensioned component includes a basalt fiber anchor rod 1, an epoxy resin filling layer 2, a pressure-bearing nut (first prefabricated nut) 3, a steel casing connector - a threaded steel casing 4, a fiberglass nut (second prefabricated nut) 5, an anchor tray made of fiberglass 6, a sealing and centering dual-purpose upper rubber ring 7, and a sealing and centering dual-purpose lower rubber ring 8. The rebar sleeve connector—a threaded steel sleeve 4—has an inner cavity, into which the basalt fiber anchor 1 is sleeved and connected to the rebar sleeve connector 4 via a filling layer 2. The rebar sleeve connector 4 also has external threads that mate with a first precast nut and a second precast nut, respectively. The first precast nut counter-rotates and engages with the outer threads of the rebar sleeve connector to form a first end, while the second precast nut rotates forward and engages with the outer threads of the rebar sleeve connector to form a second end. The anchor tray is connected to the second precast nut and faces away from the first end. A dual-purpose sealing and centering rubber ring is positioned in the gap between the basalt fiber anchor and the rebar sleeve connector. The filling layer 2, formed by a 2:1 epoxy resin adhesive filler mixture, fills the gap between the threaded steel sleeve 4 and the basalt fiber anchor 1 and provides adhesion between the basalt fiber anchor and other materials.

[0056] See also Figure 5 The pre-tensioned deformation composite structure includes several support rods arranged parallel to the slope drilling axis. The longitudinal steel frame 13 uses six steel bars evenly distributed in a circular pattern, providing support points for the bottom hole fixing plate 25 (bottom hole fixing member), the end fixing plate 26 (end fixing member), and the steel wire binding ring 14. The steel wire binding ring 14 uses steel wire wrapped in a circular pattern around the exterior of the longitudinal steel frame 13 to provide fixed integration. The bottom hole grouting pipe 15, deep grouting pipe 16, shallow grouting pipe 17, end grouting pipe 18, and exhaust pipe 19 all use PTFE and PFA inner tube hoses to connect the grouting components and grouting sections to complete the grouting. The deep grouting bladder 23 (second grouting bladder) and shallow grouting bladder 24 (first grouting bladder) are made of high-toughness expandable material, with through holes and semi-through holes reserved in the middle to connect related pipelines and steel frames. The bottom fixing plate 25 (bottom fixing piece) and the end fixing plate 26 (end fixing piece) are made of PVC plastic sheets to make disc-shaped fixing plates. The bottom fixing plate 25 and the end fixing plate 26 are reserved with corresponding pipeline holes and steel frame holes according to their uses, which is convenient for fixing and integrating the pre-tensioned deformation composite structure of the double slurry stop components, and the overall construction is convenient. The space between the bottom hole fixing piece and the second grouting stop piece forms a bottom hole grouting section, the space between the second grouting stop piece and the first grouting stop piece forms a free section, and the space between the first grouting stop piece and the end fixing piece forms an end grouting section, wherein one end of the basalt fiber anchor rod, the bottom hole grouting pipe and several support rods are all fixed to the bottom hole fixing piece, the first grouting stop piece and the second grouting stop piece are both preset with through holes and semi-through holes, the other end of the bottom hole grouting pipe is fixed to the semi-through hole of the second grouting stop piece, the deep grouting pipe passes through the end fixing piece, the through hole of the first grouting stop piece is fixed to the semi-through hole of the second grouting stop piece, the shallow grouting pipe passes through the end fixing piece and is fixed to the semi-through hole of the first grouting stop piece, the end grouting pipe passes through the end fixing piece and its slurry outlet is located between the first grouting stop piece and the end fixing piece, the exhaust pipe passes through the end fixing piece, the through hole of the second grouting stop piece and the through hole of the first grouting stop piece, the support rod passes through the end fixing piece, the through hole of the second grouting stop piece and the through hole of the first grouting stop piece and the bottom hole fixing piece.

[0057] Basalt fiber anchor 1 is constructed from a basalt fiber-epoxy resin composite material, boasting lightweight, high tensile strength, and high corrosion resistance. Epoxy adhesive 2, a 2:1 mixture, is applied between the threaded steel casing and the basalt fiber anchor 1. This adhesive is suitable for bonding basalt fiber anchors to other materials. A suitable bond spacing of 1mm maximizes the tensile properties of the basalt fiber anchor, minimizing shear failure and preserving the overall tensile strength of the basalt fiber anchor. Furthermore, the 2:1 mixed, strong-peel epoxy adhesive exhibits superior tensile performance to a 1:1 mixed epoxy adhesive at the same gap distance. The tensile strength values ​​described above were tested according to the method specified in "GB / T 30022-2013 Test Methods for Basic Mechanical Properties of Fiber-Reinforced Composite Bars." The pressure nut 3 is made of 45 steel, with a left-handed internal thread, which is counter-rotated to the outer surface of the threaded steel casing 4, providing direct contact between the pressure-bearing surface and the pressure-applying surface of the pressure-applying equipment, and providing tensioning force to the threaded steel casing 4 and the basalt fiber anchor 1; the threaded steel casing 4 is made of 45 steel, which provides sufficiently hard rigidity and is easy to produce. The outer surface is threaded with triangular thread teeth, and is used for tensioning and locking with prefabricated nuts. The inner surface is made of a rough surface to increase the bonding tension of the epoxy resin glue to the basalt fiber anchor; the fiberglass nut 5 is made of fiberglass, which is screwed on the outer surface of the basalt fiber anchor 1. When the prestressing force reaches the target value, the thread is tightened to buckle the top of the fiberglass tray 6, which plays a role in locking and retaining the pre-tensioned state; the fiberglass tray 6 is made of fiberglass, which meets the rigidity requirements and is easy to produce. The pressure-bearing structure with a square bottom and arched top increases the compressive resistance and reduces the longitudinal compressive deformation displacement. The arch top and the fiberglass nut 5 Direct contact facilitates the direct buckling of the locking force on the FRP tray 6. The square bottom plate of the FRP tray 6 is attached to the surface of the slope beam to provide a stable support and play a role in integrating prestressing. The sealing centering dual-purpose upper end / (lower end) rubber ring 7 / (8) is inserted into the gap between the basalt fiber anchor rod 1 and the threaded steel sleeve 4. First, a circle of the sealing centering dual-purpose lower end rubber ring 8 is inserted into the gap at the lower end of the threaded steel sleeve 4 to prevent leakage from the lower end when injecting the epoxy resin glue 2. After the epoxy resin glue 2 is filled, another circle of the sealing centering dual-purpose upper end rubber ring 7 is inserted into the gap at the upper end of the sleeve 4 to play a sealing role and ensure that nothing else will invade and affect the adhesiveness during the static process. Since the sealing centering dual-purpose rubber ring 7 / (8) has the same thickness, it can play the role of centering the basalt fiber anchor rod 1 by using its elasticity when inserted into the gap. The sealing centering dual-purpose rubber ring 7 / (8) plays a good sealing centering dual-purpose effect.

[0058] The present invention also discloses an on-site construction method for a basalt fiber anchor double-stop slurry bag prestressed structure, which assembles pre-tensioned components to form a complete set of pre-tensioned components and achieves a pre-tensioning effect. The specific method includes the following steps:

[0059] Step 1: Please refer to Figure 5 , drill and clean the hole, put in the prestressed anchor structure containing the pre-tensioned deformation composite structure, ensure that the grouting pipe at the bottom of the hole is located on the side close to the bottom of the hole, place the slope reaction member 12 on the slope surface, insert the FRP tray 6, and then screw in the FRP nut 5 to fit with the FRP tray 6. The FRP anchor tray 6 is connected to the FRP nut 5 and faces the direction of the bottom of the hole;

[0060] Step 2: Bond the threaded steel casing 4 to the basalt fiber anchor 1. Design the expected fixed position of the threaded steel casing 4 according to the height of the pressurizing equipment 10 and the length of the basalt fiber anchor 1, and put a sealing and centering dual-purpose lower end rubber ring 8 on the lower end of the designed position of the threaded steel casing 4; then insert the threaded steel casing 4 to the preset fixed position, and at the same time, insert the sealing and centering dual-purpose lower end rubber ring 8 into the gap between the threaded steel casing 4 and the basalt fiber anchor 1 to complete the sealing and centering of the lower end of the casing; then inject the adhesive filler epoxy resin glue 2 into the gap until it overflows, and then insert the sealing and centering dual-purpose upper end rubber ring 7 into the gap at the upper end of the casing to complete the sealing and centering of the upper end of the casing; let the epoxy resin glue 2 stand and solidify to complete the bonding of the threaded steel casing 4 and the basalt fiber anchor 1;

[0061] Step 3: Make the reaction base 11 of the pressure device, and insert the pressure device 10 into the basalt fiber anchor 1. Then screw the pressure nut 3 into the threaded steel sleeve 4 until it is close to the pressure bearing surface of the pressure device 10 and connects with the pressure bearing surface of the pressure device. This completes the installation of the pressure accessories.

[0062] Step 4: Start the first grouting and inject grout into the deep grouting pipe 16, so that the deep grouting sac 23 (second grouting component) expands to block the hole opening at that position. As the deep grouting sac 23 (second grouting component) is full, the grouting will flow through the bottom hole grouting pipe 15 to the bottom hole grouting section 20. If grouting is seen flowing out of the exhaust pipe 19, it means that the bottom hole grouting section 20 is filled and the grouting can be stopped.

[0063] Step 5: Start prestressing. When the grouting at the bottom of the hole reaches the designed strength, the pressure device 10 can be turned on to push the pressure nut 3. After the designed prestress value is reached, the pressure device 10 maintains a steady pressure state to continuously tension the basalt fiber anchor 1.

[0064] Step 6: Second grouting: Grout into the shallow grouting pipe 17 until the pressure of the pressure pump is no longer stable, indicating that the shallow grouting bag 24 (the first grouting component) has been filled. Then, grout into the end grouting pipe 18 until grout overflows from the orifice, indicating that the end grouting section 22 has been filled. Grouting can then be stopped.

[0065] Step 7: Let it stand until the end grouting reaches the designed strength, then relieve the pressure on the pressurizing device 10, remove the relevant pressurizing accessories, and tighten the FRP nut 5 to fit it with the FRP tray 6. At this point, the entire on-site construction process of the double-stop slurry bag fully bonded prestressed anchor bolt is completed.

[0066] In another embodiment, the threaded steel sleeve 4 of the steel bar sleeve connector used in the present invention can also be a left-handed threaded steel sleeve, and the external thread of the left-handed threaded steel sleeve is respectively adapted to the pressure-bearing nut 3 and the fiberglass reinforced plastic nut 5. For example, the pressure-bearing nut 3 rotates forward to connect with the external thread of the left-handed threaded steel sleeve to form the second end, and the fiberglass reinforced plastic nut 5 rotates backward to connect with the external thread of the left-handed threaded steel sleeve to form the first end. Therefore, when the prefabricated nut rotates forward to connect with the threaded steel sleeve, when the prestress reaches the target value, the thread is tightened to buckle the top of the fiberglass reinforced plastic anchor tray 6, thereby locking and retaining the pre-tensioned state; while the prefabricated nut rotates backward to connect with the threaded steel sleeve provides a pressure-bearing surface and is in direct contact with the pressure surface of the pressure-applying device, thereby providing tensioning force to the threaded steel sleeve 4 and the basalt fiber anchor rod 1. Correspondingly, the fiberglass anchor tray 6 is connected to the pressure nut 3 and faces away from the first end; the sealing and centering dual-purpose rubber ring is arranged in the gap between the basalt fiber anchor rod and the left-handed threaded steel casing, playing the role of sealing and centering.

[0067] In another different embodiment, the threaded steel sleeve 4 of the steel bar sleeve connector is a right-hand threaded steel sleeve, and its external thread is compatible with the glass fiber reinforced plastic nut 5. In this way, two glass fiber reinforced plastic nuts 5 are used as the first prefabricated nut and the second prefabricated nut, respectively. For example, one glass fiber reinforced plastic nut 5 is rotated to connect with the external thread of the right-hand threaded steel sleeve to form the second end, and the other glass fiber reinforced plastic nut 5 is rotated to connect with the external thread of the right-hand threaded steel sleeve to form the first end. Therefore, when the prestressing force reaches the target value, the glass fiber reinforced plastic nut 5 can be tightened to buckle the top of the glass fiber reinforced plastic anchor tray 6 to lock and retain the pre-tensioned state. It can also provide a pressure-bearing surface and direct contact with the pressure surface of the pressure-applying equipment, thereby providing tensioning force to the threaded steel sleeve 4 and the basalt fiber anchor rod 1.

[0068] The double-stop slurry bag prestressed structure of the basalt fiber anchor provided by the present invention separates the grouting section by the first stop slurry component and the second stop slurry component. The free section reserved in the middle provides pre-tensioning deformation space. The threaded steel casing and the nut tray provide a grip for pre-tensioning and play the role of preliminary locking. After the end grouting section solidifies, the final locking is completed. The prestress will be mainly maintained by the end grouting section and the bottom grouting section, bearing the subsequent larger tonnage anchoring deformation force, while the nut tray provides auxiliary locking and bears a small part of the force. This structure not only provides a way to use basalt fiber anchor prestressing scenarios, but also greatly improves the prestressed anchoring tonnage, which can meet the needs of a wider range of application scenarios.

[0069] The construction method of the present invention effectively coordinates the pre-tensioned components and the pre-tensioned deformation composite structure to complete the on-site use and placement of the double-stop slurry bag prestressed structure of the basalt fiber anchor. The adhesion of the threaded steel casing and the epoxy resin glue is used as a grip for the tensioned basalt fiber anchor to provide support for the stable tensioning of the basalt fiber anchor. The three-time grouting of the pre-tensioned deformation composite structure completes the locking of the prestress of the basalt fiber anchor. This construction method gives full play to the role of each part of the double-stop slurry bag prestressed structure and achieves the purpose of large-tonnage pre-tensioning of basalt fiber anchors. Through the above method, the present invention not only realizes the active pre-tensioning anchoring of the basalt fiber anchor, but also provides higher anchoring stability, tensile strength and durability, effectively expanding the application range of fiber composite bars such as basalt fiber anchors in slope protection projects.

[0070] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of this application, this does not limit the scope of patent protection of this application. All technical solutions generated by replacing or modifying equivalent structures or equivalent processes based on the essential concepts of this application using the contents recorded in the specification and drawings of this application, as well as directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are included in the scope of patent protection of this application.

Claims

1. Basalt fiber anchor double stop slurry bag prestressed structure, characterized by: Including pre-tensioned components and pre-tensioned deformation composite structures; The pre-tensioned component includes: basalt fiber anchor rod, filling layer, steel casing connector, first prefabricated nut, second prefabricated nut, anchor tray and sealing and centering dual-purpose rubber ring, wherein, The steel sleeve connector is provided with an inner cavity, the basalt fiber anchor rod is sleeved in the inner cavity of the steel sleeve connector and is connected to the steel sleeve connector through the filling layer; the steel sleeve connector is also provided with an external thread, and the external thread is adapted to a first prefabricated nut and a second prefabricated nut respectively; the first prefabricated nut is connected to the external thread of the steel sleeve connector by counter-rotation to form a first end, and the second prefabricated nut is connected to the external thread of the steel sleeve connector by forward rotation to form a second end; the anchor tray is connected to the second prefabricated nut and faces away from the first end; the sealing and centering dual-purpose rubber ring is provided in the gap between the basalt fiber anchor rod and the steel sleeve connector; The pre-tensioned deformation composite structure includes: a number of support rods arranged parallel to the slope hole axis, a bottom hole fixing piece, an end fixing piece, a first grouting part, a bottom hole grouting pipe, a deep grouting pipe, a shallow grouting pipe, a second grouting part, an end grouting pipe and an exhaust pipe. The support rods are steel frames, and the number of support rods is more than four. It also includes a binding ring wrapped around the outer periphery of the support rods. The space between the bottom hole fixing piece and the second grouting part forms a bottom hole grouting section, the space between the second grouting part and the first grouting part forms a free section, and the space between the first grouting part and the end fixing piece forms an end grouting section, wherein, One end of the basalt fiber anchor rod, bottom hole grouting pipe and several support rods are all fixed to the bottom hole fixing piece, the first grouting part and the second grouting part are both flexible accommodating chambers with pre-set through holes and semi-through holes, the other end of the bottom hole grouting pipe is fixed to the semi-through hole of the second grouting part, the deep grouting pipe passes through the end fixing piece and the through hole of the first grouting part and is fixed to the semi-through hole of the second grouting part, the shallow grouting pipe passes through the end fixing piece and is fixed to the semi-through hole of the first grouting part, the end grouting pipe passes through the end fixing piece and its slurry outlet is located between the first grouting part and the end fixing piece, the exhaust pipe passes through the end fixing piece, the through hole of the second grouting part and the through hole of the first grouting part, the support rod passes through the end fixing piece, the through hole of the second grouting part and the through hole of the first grouting part and the bottom hole fixing piece.

2. The basalt fiber anchor double-stop slurry bag prestressed structure according to claim 1 is characterized in that: Along the extension direction of the slope drilling hole, at least 1m of length is reserved for the bottom grouting section and the end grouting section, and the remaining length is the length of the free section.

3. The basalt fiber anchor double-stop slurry bag prestressed structure according to claim 1 is characterized in that: The inner diameter of the steel bar sleeve connector is 2 mm larger than the diameter of the basalt fiber anchor rod.

4. The basalt fiber anchor double-stop slurry bag prestressed structure according to claim 1 is characterized in that: The sealing and centering dual-purpose rubber ring includes a sealing and centering dual-purpose upper rubber ring and a sealing and centering dual-purpose lower rubber ring, wherein the sealing and centering dual-purpose lower rubber ring is arranged at the upper end of the preset reaction base of the pressurizing equipment and in the gap between the basalt fiber anchor rod and the steel sleeve connector.

5. A construction method for a basalt fiber anchor rod double-stop slurry bag prestressed structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: Drilling and cleaning the hole, placing the basalt fiber anchor and the pre-tensioned deformation composite structure into the hole, and the bottom hole grouting pipe is located on the side close to the bottom of the hole; S2: placing the slope reaction member and inserting it into the anchor tray, wherein the anchor tray is connected to the second prefabricated nut and faces the bottom of the hole; S3: placing the sealing and centering dual-purpose lower end rubber ring at the first preset position of the basalt fiber anchor rod, sleeve the steel bar sleeve connector on the basalt fiber anchor rod, and connect it to the sealing and centering dual-purpose lower end rubber ring, wherein the sealing and centering dual-purpose lower end rubber ring is used to seal the gap formed by the steel bar sleeve connector and the basalt fiber; S4: Injecting adhesive material into the gap between the steel casing connector and the basalt fiber anchor rod, so that the adhesive material fills the entire gap in the casing; placing the upper end rubber ring for sealing and centering at the second preset position of the basalt fiber anchor rod; S5: Sleeve the reaction base of the pressurizing device on the basalt fiber anchor and place it in the first preset position, screw the first prefabricated nut onto the outer wall of the steel bar sleeve connector and connect it to the pressure-bearing surface of the pressurizing device; S6: injecting grout into the deep grouting pipe so that the second grouting stopper blocks the orifice at that position, and the overflowing grout flows to the bottom grouting section through the bottom grouting pipe. When slurry flows out of the exhaust pipe, the grouting is stopped; S7: When the grouting section at the bottom of the hole reaches the designed strength, the pressurizing device is turned on to push the first prefabricated nut. After the designed prestress value is reached, the pressurizing device maintains a steady pressure state to continuously tension the basalt fiber anchor. S8: Grouting is injected into the shallow grouting pipe until the pressure value displayed by the pressure pump changes, and then grouting is injected into the end grouting pipe until the grouting overflows from the orifice, and then the grouting is stopped; S9: Let it stand until the end grouting section reaches the designed strength, relieve the pressure on the pressurizing device, remove the pressurizing device, and tighten the second prefabricated nut to engage it with the anchor tray.

6. The construction method of the basalt fiber anchor double-stop slurry bag prestressed structure according to claim 5 is characterized in that: The steel bar sleeve connector, the first prefabricated nut and the second prefabricated nut are all made of 45 steel.

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