High-temperature-resistant full-time online monitoring intelligent steel strand anchor rod and manufacturing method thereof

Abstract

The invention discloses a high-temperature-resistant full-time online monitoring intelligent steel strand anchor rod. The high-temperature-resistant full-time online monitoring intelligent steel strand anchor rod is composed of an intelligent steel strand, an anchor bearing plate and an anchorage device. The intelligent steel strand is formed by twisting and pressing one intelligent rib and six high-strength steel wires through a stranding machine to be combined into a circle, and the intelligent rib is located in the center of the intelligent steel strand. The intelligent steel strand is inserted into a side slope through an anchor bearing plate, then grouting materials are poured, after solidification, after the strength reaches the standard, prestress tensioning is conducted, the optical fiber of the leading-out position section is protected through a protection material to be connected with a demodulator, and after tensioning and anchor sealing are completed, the high-temperature-resistant full-time online monitoring intelligent steel strand prestress anchor rod can be manufactured. The slope anchor rod steel strand stress can be monitored, intelligent construction and development of the slope industry are promoted, and the slope anchor rod steel strand stress monitoring device has good application prospects.

Description

Technical Field

[0001] The present invention relates to a prestressed steel strand, and in particular to a high-temperature resistant, full-time online monitoring intelligent steel strand anchor rod and a manufacturing method thereof, belonging to the technical field of metal product manufacturing, processing and application. Background Art

[0002] As the core load-bearing component of the prestressed concrete system, the safety of the steel strand directly determines the overall structural safety and, more importantly, the project's service life. Steel strands are typically composed of multiple high-strength steel wires. A common 1×7 structural steel strand is made by twisting seven wires into a circular cross-section using a stranding machine. In slope prestressing systems, the strands are anchored to the anchor pad using anchors (clips). The prestressing process is as follows: After the strands are inserted into the anchor pad, they are clamped and secured with clips, followed by grouting. Prestressing is then applied after the grouting material has set to 75% or above of its design strength. After prestressing is complete, the excess strands are sawed off, and the anchor heads are protected with concrete seals.

[0003] Because these components often serve in outdoor environments and are subject to long-term erosion by rain or groundwater, the stress state of the internal steel strands directly affects the component's service life. Therefore, to accurately assess the stress state of the steel strands, it is necessary to design smart steel strands with internal stress detection capabilities.

[0004] The intelligent steel strand monitoring system enables real-time stress monitoring and high-precision data collection. Based on a four-level early warning mechanism, it quickly detects stress anomalies and issues corresponding warning signals. This mechanism is divided into four levels, from low to high: blue, yellow, orange, and red. When monitoring data triggers a different warning level, the system automatically synchronizes information with relevant departments. For example, under a blue warning, maintenance and repair departments can plan inspections in advance to identify areas with potential hazards. Under a yellow warning, relevant departments must initiate emergency response plans. An orange warning requires maintenance and repair departments to immediately implement reinforcement measures, while rescue teams must simultaneously assemble and standby. Under a red warning, rescue teams must respond swiftly, deploy resources scientifically, optimize rescue procedures, and initiate rescue operations without delay. The system also accurately locates damaged steel strands, assesses the extent of damage, and assesses the safety status of the structure. Through sharing monitoring data and conducting joint drills, rescue personnel can gain in-depth knowledge of the response procedures at different warning levels, enhancing the timeliness and accuracy of emergency responses and effectively reducing accident losses. Summary of the Invention

[0005] This invention addresses the functional implementation of a high-temperature, full-time online monitoring smart steel strand anchor and its manufacturing method. This design utilizes a composite "smart bar" made of high-temperature insulating material and steel wire. The bar incorporates a fiber Bragg grating (FBG) stress sensor, enabling real-time stress data collection. During the stranding process, high-temperature treatment and tension control are utilized to create an integrated structure that synergizes the stresses of the strands, enabling full-time online monitoring and early warning of the stress state of the component's steel strands.

[0006] A high-temperature resistant, full-time online monitoring smart steel strand anchor rod, the anchor rod consisting of a smart steel strand, an anchor pad, and an anchor; the smart steel strand is formed into a circular shape by twisting, pressurizing, and heat-treating one smart tendon and six steel wires on a stranding machine; the smart tendon is composed of one optical cable and one layer of polytetrafluoroethylene protective layer; the optical cable is made of insulating material and carbon fiber armor, and is composed of, from the inside to the outside, an optical fiber in the center, an optical fiber loose tube, carbon fiber, and high-temperature resistant glue; a grating is set every 3 meters along the entire length of the optical fiber; the smart tendon is located in the center of the smart steel strand.

[0007] A method for manufacturing a high-temperature resistant full-time online monitoring intelligent steel strand anchor rod; comprising the following steps: Step 1: Paying off: Place 6 high-strength steel wires on the pay-off device of the stranding machine, and place a pre-prepared smart bar in the center of the pay-off device of the stranding machine; Step 2: Twisting: The high-strength steel wire and smart bar are first gathered in front of the tile mouth through the wire divider, with the smart bar in the center. Then they are twisted through the tile mouth and then pass through the mold to form the smart steel strand; Step 3: Pulling, tensioning, high temperature, and coiling: Pulling the smart steel strand containing the smart reinforcement, applying 90kN tension through a tension pulley, and then passing through an intermediate frequency furnace at 370°C to eliminate stress before coiling. Step 4: Splitting, packaging, and transportation: Pass one end of the smart steel strand through the I-spool and insert it into the other splitting I-spool. Use the I-spool to pull the smart steel strand into a certain length and pack it for temporary storage, waiting for transportation to the construction site. During transportation, the smart steel strand must be properly fixed to prevent collision and friction damage. During lifting and transportation, dragging and collision are prohibited and it must be handled with care. Step 5: Anchoring and Monitoring: Cut the smart steel strand according to the slope construction drawings, insert it into the slope through the anchor pad and anchor, strip out the optical fiber, lead it through the protective device and connect it to the demodulator. Pour the debugged grouting material and wait for it to reach the solidification strength standard before prestressing. During the prestressing process, the demodulator can read the prestressing value of the smart steel strand to complete the monitoring. Construction workers, supervisors, and owners can achieve remote monitoring through the pre-installed mobile phone app and PC port. Step 6: Anchor sealing: After completing prestressing, cut off the excess steel wire and connect the lead-out section to the demodulator through a protective cover. Debug and protect the connection between the smart steel strand and the demodulator, and use concrete or anti-rust paint to complete the anchor sealing protection.

[0008] Beneficial effects: It can realize the monitoring and early warning of the full-time stress working environment of the steel strands inside the anchor rod, conduct safety monitoring of the long-term operation of the component, and improve the service life of the component. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Schematic diagram of the installation of smart steel strand anchor rod for stress measurement.

[0010] Figure 2 for Figure 1 Schematic diagram of the Zhongzhihui steel strand structure.

[0011] Figure 3 for Figure 2 Schematic diagram of the structure of the wisdom muscle.

[0012] Figure 4 Schematic diagram of the cross-sectional structure of optical fiber fusion protection.

[0013] In the figure: 1- smart steel strand, 2- anchor plate and anchor, 3- smart reinforcement, 3-1 optical cable, 3-2 polytetrafluoroethylene protective layer, 3-1-1 optical fiber, 3-1-2 optical fiber loose tube, 3-1-3 carbon fiber, 3-1-4 high temperature resistant glue, 4- high strength steel wire, 5- protective sleeve, 5-1 waterproof rubber plug, 5-2 waterproof cap, 5-3 compression tube, 5-4 armored empty tube, 5-4-1 high performance fiber cloth, 5-4-2 stainless steel braided wire, 5-4-3 stainless steel threaded tube, 5-5-4 polyvinyl chloride outer sheath DETAILED DESCRIPTION

[0014] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0015] A high-temperature resistant, full-time online monitoring smart steel strand anchor rod, the anchor rod consisting of a smart steel strand 1, an anchor pad and an anchor 2; the smart steel strand 1 is composed of a smart rib 3 and six steel wires 4, which are twisted, pressed and heat-treated by a stranding machine to form a circular shape; the smart rib 3 is composed of an optical cable 3-1 and a layer of polytetrafluoroethylene protective layer 3-2; the optical cable 3-1 is made of insulating material and carbon fiber armor, and is composed of an optical fiber 3-1-1 in the center, an optical fiber loose tube 3-1-2, carbon fiber 3-1-3, and high-temperature resistant glue 3-1-4 from the inside to the outside; a grating is set every 3 meters along the entire length of the optical fiber 3-1-1; the smart rib 3 is located in the center of the smart steel strand 1.

[0016] The leading end of the smart reinforcement 3 is 200 cm away from the plane of the anchor plate and the anchor 2.

[0017] The smart steel strand 1 is inserted into the slope through the anchor plate and the anchor 2 and is perpendicular to the central axis of the tensioning hydraulic jack.

[0018] The anchor plate and the anchor 2 are filled with grouting material 6. After the grouting material solidifies, prestressing is performed until the strength reaches the standard. After completion, the excess smart steel strand 1 is cut off and a sufficient length of optical fiber 3-1-1 is reserved.

[0019] After the optical fiber 3-1-1 is fusion-spliced, the outlet protective cover 5 is installed on the smart rib 3 and the waterproof rubber plug 5-1 and the waterproof cap 5-2 are fixed. Then, the crimping tube 5-3 is installed and locked on the waterproof cap 5-1. The armored empty tube 5-4 is put on the optical fiber pigtail extension line and crimped together with the crimping tube 5-3. The optical fiber pigtail is connected to the demodulator through the armored empty tube 5-4 to complete the wiring.

[0020] The armored hollow tube 5-4 is composed of high-performance fiber cloth 5-4-1, stainless steel braided wire 5-4-2, stainless steel threaded tube 5-4-3, and polyvinyl chloride outer sheath 5-4-4.

[0021] After the protective cover 5 is installed, a cross anchor or other anchoring method connection component is reserved according to the requirements of the architectural drawings, and concrete or anti-rust paint is used for sealing protection. After completion, the slope anchor is successfully constructed.

[0022] The diameter of the smart tendon 3 is at least 2.5% larger than the diameter of the high-strength steel wire 4; The grouting material 6 is cement mortar or cement slurry prepared according to special geological conditions.

[0023] A method for manufacturing a high-temperature resistant full-time online monitoring intelligent steel strand anchor rod; comprising the following steps: Step 1: Paying off the wire: 6 high-strength steel wires (4) are placed on the pay-off device of the stranding machine, and a pre-prepared smart tendon (3) is placed at the center of the pay-off device of the stranding machine; Step 2, twisting: The high-strength steel wire (4) and the smart rib (3) are first gathered in front of the tile mouth through the wire divider, with the smart rib (3) in the center, and then twisted through the tile mouth, and then formed into the smart steel strand (1) through the mold; Step 3: traction, tension, high temperature, and coiling: traction of the smart steel strand (1) containing the smart tendon (3), applying 90KN tension through a tension wheel, and forming a coil after eliminating stress at a high temperature of 370°C in a medium frequency furnace; Step 4: Splitting, packing and transporting: one end of the smart steel strand (1) is passed through the I-shaped wheel and inserted into the other splitting I-shaped wheel. The smart steel strand (1) is pulled by the I-shaped wheel to split the strand into a certain length and packed for temporary storage. The smart steel strand is then transported to the construction site for storage by a vehicle. During transportation, the smart steel strand must be properly fixed to prevent collision and friction damage. During lifting and transportation, dragging and collision are prohibited and the strand must be handled with care. Step 5, anchoring and monitoring: Cut the smart steel strand (1) according to the requirements of the slope construction drawing, insert it into the slope through the anchor plate and anchor (2), peel out the optical fiber (3-1-1), lead it out through the protection device and connect it to the demodulator, pour the debugged grouting material and wait for its solidification strength to meet the standard before prestressing. During the tensioning, the prestressing size of the smart steel strand can be read through the demodulator to complete the monitoring. The construction workers, supervisors and owners can realize remote monitoring through the mobile phone APP and computer PC port installed in advance; Step 6: Anchor sealing: After completing the prestressing, cut off the excess steel wire and connect the lead-out section to the demodulator through the protective cover. Debug and protect the connection between the smart steel strand (1) and the demodulator, and use concrete or anti-rust paint to complete the anchor sealing protection.

Claims

1. A high temperature resistant full-time online monitoring intelligent steel strand anchor rod, characterized in that: The anchor rod is composed of a smart steel strand (1), an anchor pad and an anchor (2); the smart steel strand (1) is composed of a smart rib (3) and six steel wires (4) twisted, pressed and heat-treated by a stranding machine to form a circle; the smart rib (3) is composed of a fiber optic cable (3-1) and a polytetrafluoroethylene protective layer (3-2); the fiber optic cable (3-1) is made of insulating material and carbon fiber armor, and is composed of an optical fiber (3-1-1) in the center, an optical fiber loose tube (3-1-2), a carbon fiber (3-1-3) and a high-temperature resistant glue (3-1-4) from the inside to the outside; a grating is set every 3 meters along the entire length of the optical fiber (3-1-1); the smart rib (3) is located at the center of the smart steel strand (1).

2. The high-temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: The leading end of the smart reinforcement (3) is 200 cm away from the plane of the anchor plate and the anchor (2).

3. The high-temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: The smart steel strand (1) is inserted into the slope through the anchor plate and the anchor (2), and is perpendicular to the central axis of the tensioning hydraulic jack.

4. The high-temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: Grouting material (6) is poured into the anchor plate and the anchor (2). After the grouting material solidifies, prestressing is performed until the strength reaches the standard. After completion, the excess smart steel strand (1) is cut off and a sufficient length of optical fiber (3-1-1) is reserved.

5. The high temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: After the optical fiber (3-1-1) is fused, the outlet protective cover (5) is installed on the smart rib (3) and the waterproof rubber plug (5-1) and the waterproof cap (5-2) are fixed. Then, the crimping tube (5-3) is installed and locked on the waterproof cap (5-1). The armored hollow tube (5-4) is placed on the optical fiber pigtail extension line and crimped together with the crimping tube (5-3). The optical fiber pigtail is connected to the demodulator through the armored hollow tube (5-4), and the wiring is completed.

6. The high temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: The armored empty tube (5-4) is composed of high-performance fiber cloth (5-4-1), stainless steel braided wire (5-4-2), stainless steel threaded tube (5-4-3), and a polyvinyl chloride outer sheath (5-4-4).

7. The high temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: After the protective cover (5) is installed, a cross anchor or other anchoring method connection member is reserved according to the requirements of the architectural drawings, and concrete or anti-rust paint is used for sealing protection. After completion, the slope anchor rod is successfully constructed.

8. The high temperature resistant full-time online monitoring intelligent steel strand anchor rod according to claim 1, characterized in that: The diameter of the smart tendon (3) is at least 2.5% larger than the diameter of the high-strength steel wire (4); The grouting material (6) is cement mortar or cement slurry prepared according to special geological conditions.

9. A method for manufacturing a high-temperature resistant, full-time online monitoring intelligent steel strand anchor rod as claimed in claim 1; characterized in that: The following implementation steps are also included: Step 1: Paying off the wire: 6 high-strength steel wires (4) are placed on the pay-off device of the stranding machine, and a pre-prepared smart tendon (3) is placed at the center of the pay-off device of the stranding machine; Step 2, twisting: The high-strength steel wire (4) and the smart rib (3) are first gathered in front of the tile mouth through the wire divider, with the smart rib (3) in the center, and then twisted through the tile mouth, and then formed into the smart steel strand (1) through the mold; Step 3: traction, tension, high temperature, and coiling: traction of the smart steel strand (1) containing the smart tendon (3), applying 90KN tension through a tension wheel, and forming a coil after eliminating stress at a high temperature of 370°C in a medium frequency furnace; Step 4: Splitting, packing and transporting: one end of the smart steel strand (1) is passed through the I-shaped pulley and inserted into another splitting I-shaped pulley, and the smart steel strand (1) is pulled by the I-shaped pulley to split the strands into certain lengths and packed for temporary storage, waiting for transportation to the construction site for storage; Step 5, anchoring and monitoring: cut the smart steel strand (1) according to the requirements of the slope construction drawing, insert it into the slope through the anchor plate and anchor (2), peel out the optical fiber (3-1-1), lead it out through the protective device and connect it to the demodulator, pour the debugged grouting material and perform prestressing after its solidification strength reaches the standard; Step 6: Anchor sealing: After completing the prestressing, cut off the excess steel wire and connect the lead-out section to the demodulator through the protective cover. Debug and protect the connection between the smart steel strand (1) and the demodulator, and use concrete or anti-rust paint to complete the anchor sealing protection.

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