Intelligent sensing prestress steel bar structure and manufacturing method thereof

Abstract

The invention relates to the field of bridge engineering, in particular to an intelligent sensing prestress steel bar structure and a manufacturing method thereof.The intelligent sensing prestress steel bar structure comprises a steel bar, the steel bar is used for tensioning a bridge, a groove is formed in the outer wall of the steel bar, and the groove is formed in the whole body in the length direction of the steel bar in a double-spiral-line shape with the axis of the steel bar as the center line; a groove is formed in the prestressed steel bar, the groove is used for arranging a fiber grating sensor, the fiber grating sensor is used for monitoring the stress in the axial direction of the steel bar, the double-helix groove is formed in the prestressed steel bar, the fiber grating sensor is pasted on the inner wall of the groove, and the groove is arranged to be in a double-helix form, so that the stress of the prestressed steel bar is monitored. The grooves can cover the outer wall of the prestressed steel bar in a large area, the distribution range of the sensors is expanded, and the monitoring comprehensiveness and uniformity are guaranteed; the fiber grating sensor deforms along with the deformation of the groove, and is always attached to the inner wall of the groove, so that real-time and continuous monitoring can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of bridge engineering, and in particular to an intelligent sensing prestressed steel rod structure and a manufacturing method thereof. Background Art

[0002] Prestressed steel rods are one of the key components of the arch foot joint section of a long-span steel truss arch bridge. In order to ensure that the axial force and bending moment of the chord can be smoothly transmitted to the concrete arch seat and to avoid the contact surface between the pressure plate lattice of the arch foot joint section and the concrete of the arch seat foundation from being emptied, it is necessary to balance the bending moment of the chord by tensioning the prestressed steel rods outside the main chord, so that the arch foot joint section is in a fully compressed state. However, due to the large number of prestressed steel rods in the arch foot joint section, the complex structure and the large inclination angle, the emptied concrete contact surface directly affects the overall stress performance and structural safety of the bridge. Therefore, it is particularly important to monitor the stress state of the prestressed steel rods in real time and accurately.

[0003] At present, the force monitoring of prestressed steel bars usually draws on the monitoring methods of prestressed steel strands and inclined cables, such as installing pressure rings or magnetic flux sensors at the anchor end. However, these methods have significant shortcomings: first, the durability is low; second, the monitoring accuracy is limited, the magnetization process responds slowly and the data is lagging; third, the measurement error is large and is significantly affected by the external temperature, and the error usually exceeds 5%. These problems make it difficult for existing methods to meet the actual needs of high-precision and long-term monitoring. Summary of the invention

[0004] The purpose of the present invention is to provide an intelligent sensing prestressed steel bar structure and a manufacturing method thereof to address the problems of data lag and large measurement errors in traditional prestressed steel bar force monitoring in the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] In a first aspect, a steel rod structure comprises a steel rod, wherein a groove is provided on the outer wall of the steel rod, wherein the groove is arranged in a double helix shape along the length direction of the steel rod with the axis of the steel rod as the center line, and wherein the groove is used to set a fiber grating sensor, and the fiber grating sensor is used to monitor the stress in the axial direction of the steel rod.

[0007] The present invention is a steel rod structure, on which a double helical groove is arranged, and the groove is arranged along the outer wall of the steel rod with the axial direction of the steel rod as the center line. By arranging the double helical groove on the steel rod and pasting the fiber grating sensor in the groove, compared with the traditional method of arranging the steel rod at the arch foot joint section and then arranging a pressure ring or a magnetic flux sensor at the anchoring end of the steel rod, the groove of this scheme can cover the outer wall of the steel rod over a large area, expand the distribution range of the sensor, and ensure the comprehensiveness and uniformity of monitoring; when the steel rod is deformed during the tensioning process, the fiber grating sensor arranged in the groove can intuitively and accurately sense the stress distribution of the steel rod in the axial direction under different working conditions, and realize real-time and continuous monitoring. Compared with the method of arranging the pressure ring at the anchoring end, the structure of the present application can make the fiber grating sensor deform synchronously with the steel rod, and directly monitor the steel rod in real time while deforming, thereby reducing the delay of signal transmission and avoiding data lag; by arranging the double helical groove on the outer wall of the steel rod, The fiber grating sensor is embedded in the groove, which can effectively protect the sensor from external physical damage, such as collision, friction or external force, and extend the service life of the sensor; and by arranging the fiber grating sensor in the double helix groove, the cross section of the steel rod at any position has at least two fiber grating sensors to monitor the stress in the axial direction of the steel rod; by arranging the fiber grating sensor on the outer wall of the steel rod, when the steel rod is buried in the arch foot joint section during subsequent construction, the fiber grating sensor can be located in the arch foot joint section. Compared with traditional external pressure rings and magnetic flux sensors, the arrangement of the sensors in the present application can reduce the contact between the sensor and the external environment, avoid corrosion or interference to the sensor caused by external environmental factors, thereby reducing the life of the sensor. In the present application, the fiber grating sensor is arranged on the outer wall of the steel rod and buried in the arch foot joint section together with the steel rod, so that the axial stress of the steel rod can still be monitored in real time by the fiber grating sensor during the subsequent use of the bridge.

[0008] As a preferred solution of the present invention, the outer wall of the steel rod is provided with reinforcing ribs, and the reinforcing ribs are arranged in a spiral shape with the axis of the steel rod as the center line.

[0009] As a preferred solution of the present invention, the reinforcing ribs are arranged throughout the outer wall of the steel bar along the length direction of the steel bar, and the arrangement positions of the reinforcing ribs and the arrangement positions of the grooves do not interfere with each other.

[0010] When the steel rod is set at the joint section of the arch foot, the spiral reinforcement ribs form a mechanical bite with the surrounding concrete or other filling materials, which improves the grip between the steel rod and the environmental medium and reduces structural loosening or performance degradation caused by slippage.

[0011] As a preferred embodiment of the present invention, the steel rod includes a rod body and a first big head end, wherein the first big head end is connected to one end of the rod body, and a second big head end is provided at an end of the rod body away from the first big head end, wherein the cross-sectional area of ​​the first big head end is larger than the cross-sectional area of ​​the rod body, and the cross-sectional area of ​​the second big head end is larger than the cross-sectional area of ​​the rod body.

[0012] Rod heads are arranged at both ends of the rod body, which effectively increases the contact area when the subsequent steel rod is connected with the tensioning part and the anchoring part, disperses the force, thereby improving the reliability of the connection and avoiding damage caused by stress concentration.

[0013] As a preferred embodiment of the present invention, a first outward expansion section is provided between the rod body and the first large head end, and a second outward expansion section is provided between the rod body and the second large head end.

[0014] As a preferred embodiment of the present invention, the groove cross section is semicircular or rectangular.

[0015] As a preferred embodiment of the present invention, the grooves are arranged in a double helix shape with the steel rod as the center line, and the angle θ between the double helix grooves and the steel rod is 0°<θ≤90°.

[0016] In a second aspect, a method for manufacturing a prestressed steel bar, using the above-mentioned steel bar structure, the method comprises:

[0017] Process the outer surface of the steel bar to generate grooves and reinforcement ribs;

[0018] A plurality of fiber grating sensors are respectively encapsulated in the two grooves, and adjacent fiber grating sensors in one groove are connected in series;

[0019] An anchoring part is arranged at one end of the steel rod, and the anchoring part is arranged at one end of the arch foot joint section under construction;

[0020] A tensioning part is arranged at the other end of the steel rod, and the tensioning part is arranged at the other side of the arch foot joint section under construction and is arranged opposite to the anchoring part;

[0021] Complete manufacturing.

[0022] The present invention is a method for manufacturing a prestressed steel bar. Fiber grating sensors are buried in grooves on the outer wall of the steel bar, and the sensors in each groove are connected in series, so that a plurality of sensors form a monitoring network. During the construction of the bridge arch foot joint section, the method can monitor the stress in the axial direction of the steel bar in real time, so that operators can know the stress condition of the steel bar in real time.

[0023] As a preferred embodiment of the present invention, the tensioning portion is connected to the first large end, and the anchoring portion is connected to the second large end.

[0024] As a preferred embodiment of the present invention, the tensioning part includes a tensioning pad, which is located at one end of the tensioning part close to the anchoring part, and a first conical hole is provided on the tensioning pad, which is adapted to the first outward expansion section, and the tensioning pad is connected to the steel rod through the first conical hole.

[0025] By setting up a tensioning pad, the reaction force can be borne by the tensioning pad during subsequent tensioning to avoid stress concentration; the first conical hole reduces the local stress concentration of the tensioning pad and the steel rod through the uniform force distribution on the conical surface, reduces the risk of damage to the component due to fatigue or wear, and shows higher safety, especially in long-term use or harsh environments.

[0026] As a preferred solution of the present invention, a first spiral rib is provided at one end of the tensioning pad facing the anchoring portion, and a tensioning nut is provided at one end of the tensioning pad away from the anchoring portion, and the tensioning nut is connected to the steel rod.

[0027] By arranging the first spiral tendon, the reaction force exerted on the tensioning plate during the tensioning process of the prestressed steel rod can be transmitted to the first spiral tendon, and the first spiral tendon can have the effect of dispersing the force (that is, the design of the first spiral tendon can evenly disperse the reaction force exerted on the tensioning plate to the tendon surface during the tensioning process, effectively avoiding single-point force or local stress concentration, reducing fatigue damage in the local area of ​​the tensioning plate, and improving the mechanical properties and durability of the overall component); through the force distribution effect of the first spiral tendon, the bearing capacity of the tensioning plate and the nut is more uniform, reducing fatigue damage or crack propagation caused by stress concentration, thereby significantly extending the service life of the tensioning component and the overall structure.

[0028] As a preferred embodiment of the present invention, the anchoring portion includes an anchoring pad, the anchoring pad is provided with a second conical hole, the second conical hole is adapted to the second outward expansion section, and the anchoring pad is connected to the steel rod through the second conical hole.

[0029] The anchor plate is connected to the prestressed steel rod through the second tapered hole, which helps to ensure a tight connection between the anchor part and the prestressed steel rod. This tapered hole design can provide a larger contact area and provide a stronger locking force through the geometric shape, avoiding loosening of the connection and increasing the stability of the connection.

[0030] As a preferred solution of the present invention, an anchor nut is provided at one end of the anchor plate away from the tensioning portion, and the anchor nut is connected to the steel rod; a second spiral rib is provided at one end of the anchor plate facing the tensioning portion.

[0031] The connection between the anchor nut and the prestressed steel rod can effectively apply the anchoring force and ensure that the prestressed steel rod is fully fixed during the tensioning process. The tight connection between the anchor nut and the anchor pad can enhance the stability of the overall anchoring part, prevent loosening or displacement due to external forces, and ensure that the mechanical properties of the prestressed steel rod are maintained; the design of the second spiral reinforcement helps to evenly disperse the local force applied to the anchor pad and reduce stress concentration. Through the arrangement of the spiral reinforcement, the force borne by the anchoring part can be effectively transmitted to a wider area through the spiral reinforcement, thereby reducing the uneven force of the anchor pad and improving the reliability of the entire prestressed system.

[0032] As a preferred solution of the present invention, a stop nut is provided at one end of the tensioning nut away from the tensioning pad.

[0033] The stop nut is set because during the tensioning process of the prestressed steel rod, the tensioning thread may loosen under the action of long-term load. The stop nut can lock the position of the tensioning nut to prevent the loosening of the tensioning nut from affecting the prestressed steel rod, thereby ensuring the accuracy of the measurement data.

[0034] As a preferred solution of the present invention, a first washer is provided between the tensioning nut and the tensioning pad.

[0035] The first washer can effectively disperse the local pressure exerted by the tensioning nut on the tensioning pad, avoiding uneven force on the tensioning pad due to pressure concentration. This can ensure a more balanced force transmission of the tensioning system, thereby improving the stability and uniformity of the entire prestressing system.

[0036] As a preferred solution of the present invention, a waterproof cover is provided on the tensioning portion.

[0037] The waterproof cover can effectively isolate moisture and prevent it from entering the tensioning part, especially in outdoor or humid environments. Moisture may cause metal corrosion, rust and other problems, which will affect the strength and service life of the prestressed steel rods in the long run. The waterproof cover can effectively avoid these problems and extend the service life of the equipment.

[0038] As a preferred embodiment of the present invention, the stress monitoring of the axial direction of the prestressed steel bar includes:

[0039] Aαcosθ=A1α1+A2α2;

[0040] Where: α is the stress in the axial direction of the prestressed steel rod; α1 is the stress of the fiber Bragg grating sensor; α2 is the stress along the normal plane of the double helix groove; A is the cross-sectional area of ​​the prestressed steel rod; A1 is the cross-sectional area of ​​the fiber Bragg grating sensor; A2 is the cross-sectional area of ​​the steel rod along the normal plane of the double helix; θ is the angle between the double helix groove and the steel rod.

[0041] As a preferred solution of the present invention, the two ends of the fiber Bragg grating sensor after the series connection pass through the tensioning part and the anchoring part respectively and are connected to the monitoring equipment, and the strain and stress of the fiber Bragg grating sensor are monitored by the monitoring equipment.

[0042] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0043] 1. The present invention is a steel rod structure, in which a double helical groove is arranged on the steel rod, and the groove is arranged along the outer wall of the steel rod with the axial direction of the steel rod as the center line. By arranging a double helical groove on the steel rod and pasting a fiber grating sensor in the groove, compared with the traditional method of arranging the steel rod at the arch foot joint section and then arranging a pressure ring or a magnetic flux sensor at the anchoring end of the steel rod, the groove of this scheme can cover the outer wall of the steel rod over a large area, expand the distribution range of the sensor, and ensure the comprehensiveness and uniformity of monitoring; when the steel rod is deformed during the tensioning process, the fiber grating sensor arranged in the groove can intuitively and accurately sense the stress distribution of the steel rod in the axial direction under different working conditions, and realize real-time and continuous monitoring. Compared with the method of arranging a pressure ring at the anchoring end, the structure of the present application can make the fiber grating sensor deform synchronously with the steel rod, and directly monitor the steel rod in real time while deforming, thereby reducing the delay of signal transmission and avoiding data lag; by arranging a double helical groove on the outer wall of the steel rod, Embedding the fiber grating sensor inside the groove can effectively protect the sensor from external physical damage, such as collision, friction or external force, and extend the service life of the sensor; and by arranging the fiber grating sensor in the double helix-shaped groove, the cross section of the steel rod at any position has at least two fiber grating sensors to monitor the stress in the axial direction of the steel rod; by arranging the fiber grating sensor on the outer wall of the steel rod, when the steel rod is buried in the arch foot joint section during subsequent construction, the fiber grating sensor can be located in the arch foot joint section. Compared with traditional external pressure rings and magnetic flux sensors, the arrangement of the sensors in the present application can reduce the contact between the sensor and the external environment, avoid corrosion or interference to the sensor caused by external environmental factors, and thus reduce the service life of the sensor. In the present application, the fiber grating sensor is arranged on the outer wall of the steel rod, and buried in the arch foot joint section together with the steel rod, so that the axial stress of the steel rod can still be monitored in real time by the fiber grating sensor during the subsequent use of the bridge.

[0044] 2. The present invention is a method for manufacturing prestressed steel bars. Fiber grating sensors are buried in grooves on the outer wall of the steel bars, and the sensors in each groove are connected in series, so that a number of sensors form a monitoring network. During the construction of the bridge arch foot joint section, the method can monitor the stress in the axial direction of the steel bar in real time, making it convenient for operators to know the stress condition of the steel bar in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 It is a structural schematic diagram of the intelligent sensing prestressed steel rod structure of the present invention;

[0046] Figure 2 is a cross-sectional view of a steel rod of the present invention;

[0047] Figure 3 The present invention Figure 2 A magnified image of point A;

[0048] Figure 4 It is the force diagram of the prestressed steel bar of the present invention;

[0049] Figure 5 It is a structural schematic diagram of the anchor pad of the present invention;

[0050] Figure 6 It is a structural schematic diagram of the tension pad of the present invention;

[0051] Figure 7 It is a schematic structural diagram of the steel bar of the present invention;

[0052] Figure 8 It is a flow chart of the manufacturing method of the present invention.

[0053] Icons: 1-steel rod; 11-groove; 12-fiber grating sensor; 13-rod body; 14-first expansion section; 15-second expansion section; 16-first large head end; 17-second large head end; 2-tensioning part; 21-tensioning pad; 211-first conical hole; 22-tensioning nut; 3-anchoring part; 31-anchoring pad; 311-second conical hole; 32-anchoring nut; 4-waterproof cover; 5-first spiral rib; 6-second spiral rib; 7-reinforcement rib; 8-stop nut; 9-first washer; 10-second washer. DETAILED DESCRIPTION

[0054] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0055] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "upper", "lower", "left", "right", "center", "inside", "outside", etc. are based on the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments to facilitate the technicians to quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation of the present invention.

[0056] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0057] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0058] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0059] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection 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, and it can be the internal connection of two elements.

[0060] Example 1

[0061] like Figures 1 to 3 The structure of an intelligent sensing prestressed steel rod shown includes a steel rod 1 installed on the arch bridge joint section, the steel rod 1 is provided with a groove 11 throughout, and the groove 11 is arranged in a symmetrical double helix along the axis direction of the steel rod 1, and the groove 11 is used to set a fiber grating sensor 12, the fiber grating sensor 12 is used to monitor the stress of the steel rod 1 in the axis direction during the tensioning process, and the fiber grating sensor 12 can detect the slight deformation of the surface of the steel rod 1 due to the force (such as tension). As the steel rod 1 is tensioned, the deformation of the steel rod will cause the wavelength of the fiber grating sensor 12 to change, and this change can be converted into a corresponding stress signal by a fiber grating demodulator, thereby reflecting the stress change of the steel rod 1 in the axis direction during the tensioning process in real time. Since the groove 11 of the steel rod 1 is arranged in a symmetrical double helix along the axis direction, the fiber grating sensor 12 can be evenly distributed on the surface of the steel rod, thereby ensuring that when the steel rod is stressed, the stress distribution information at different positions can be more accurately captured and transmitted.

[0062] In one or more embodiments, the steel rod 1 includes a rod body 13, and the rod body 13 is provided with a second expansion section 15 at one end facing the anchoring portion 3, and a second large head end 17 is provided at one end of the second expansion section 15 away from the rod body 13, and the outer wall of the second large head end 17 is connected to the anchoring nut 32; the rod body 13 is provided with a first expansion section 14 at one end facing the tensioning portion 2, and a first large head end 16 is provided at one end of the first expansion section 14 away from the rod body 1, and the outer wall of the first large head end 16 is connected to the tensioning nut 22. The expansion sections and the end heads are provided at both ends of the rod body 1, which effectively increases the contact area between the steel rod 1 and the nut, disperses the force, thereby improving the reliability of the connection and avoiding damage caused by stress concentration;

[0063] Furthermore, a reinforcing rib 7 is provided on the outer wall of the steel rod 1 , and the reinforcing rib 7 is arranged in a spiral shape with the axis of the steel rod 1 as the center line.

[0064] In one or several embodiments, the outer wall of the first large head end 16 is provided with a tensioning portion 2, the outer wall of the second large head end 17 is provided with an anchoring portion 3, and the tensioning portion 2, the anchoring portion 3 and the steel rod 1 constitute a prestressed steel rod.

[0065] In one or more embodiments, the tensioning part 2 includes a tensioning pad 21, which is located at one end of the tensioning part 2 facing the anchoring part 3, and a first conical hole 211 is provided on the tensioning pad 21, and the tensioning pad 21 is connected to the steel rod 1 through the first conical hole 211. The tensioning pad 21 is connected to the steel rod 1 through the first conical hole 211, so that when tensioning, the tensioning pad 21 can effectively withstand and transmit the tensioning force applied by the tensioning part 2. When the steel rod 1 is tensioned, the reaction force borne by the tensioning pad 21 is transmitted to the arch bridge joint section through its own rigid structure. Since the design of the tensioning pad 21 can absorb and buffer the reaction force, the arch bridge joint section does not directly bear the peak force generated by tensioning, reducing the risk of stress concentration in the concrete structure, such as Figure 1 and Figure 6 shown.

[0066] Furthermore, the first expansion section 14 is adapted to the first tapered hole 211, and the second expansion section 15 is adapted to the second tapered hole 311. The tapered hole structure enables the expansion section to produce a self-locking effect after being stressed, effectively preventing the steel rod from slipping or loosening, significantly improving the anchoring performance, and being suitable for high-strength prestressed working conditions, such as Figures 5 to 7 shown.

[0067] In one or more embodiments, a first spiral rib 5 is provided at one end of the tensioning pad 21 facing the anchoring portion 3. The design of the first spiral rib 5 can evenly disperse the reaction force exerted on the tensioning pad 21 to the rib surface during the tensioning process, effectively avoiding single-point force or local stress concentration, reducing fatigue damage in a local area of ​​the tensioning pad 21, and improving the mechanical properties and durability of the overall component.

[0068] Furthermore, the tensioning pad 21 is provided with a tensioning nut 22 at one end away from the first spiral rib 5. The tensioning nut 22 is threadedly connected to the steel rod 1, and can apply precise axial tensioning force to the steel rod 1 during the tensioning process. By adjusting the tightening degree of the tensioning nut 22, the stress state of the steel rod 1 can be effectively controlled;

[0069] Furthermore, a first washer 9 is provided between the tensioning nut 22 and the tensioning pad 21. The first washer 9 can effectively disperse the local pressure exerted by the tensioning nut 22 on the tensioning pad 21, thereby avoiding uneven force on the tensioning pad 21 due to pressure concentration, thereby ensuring a more balanced force transmission of the tensioning part, thereby improving the stability and uniformity of the entire steel rod structure. Figure 1 shown.

[0070] In one or more embodiments, the tensioning nut 22 is provided with a stop nut 8 at one end away from the tensioning pad 21. By providing the stop nut 8, it can be ensured that the tensioning nut 22 will not loosen under long-term load (that is, the stop nut 8 can lock the position of the tensioning nut 22 to ensure the accuracy of the measurement data). Figure 1 shown.

[0071] In one or more embodiments, a waterproof cover 4 is provided on the tensioning part 2, which can effectively isolate moisture and prevent moisture from entering the tensioning part 2, especially in outdoor or humid environments. Moisture may cause metal corrosion, rust and other problems, which will affect the strength and service life of the steel rod 1 in the long run. The waterproof cover 4 can effectively avoid these problems and extend the service life of the equipment. Figure 1 shown.

[0072] In one or several embodiments, an external thread is provided on the tensioning nut 22, and an internal thread is provided on the inner wall of the waterproof cover 4. The waterproof cover 4 and the tensioning nut 22 are connected via the external thread and the internal thread. The waterproof cover 4 and the tensioning nut 22 are arranged to be threadedly connected, which facilitates subsequent construction personnel to disassemble and assemble the waterproof cover 4 while ensuring the stability of the waterproof cover 4.

[0073] In one or more embodiments, the anchoring portion 3 includes an anchoring pad 31, and a second tapered hole 311 is provided on the anchoring pad 31. The anchoring pad 31 is connected to the steel rod 1 through the second tapered hole 311, and the anchoring pad 31 is connected to the steel rod 1 through the second tapered hole 311, which helps to ensure a tight connection between the anchoring portion 3 and the steel rod 1. The design of the second tapered hole 311 can provide a larger contact area for the steel rod 1, and provide a stronger locking force through the geometric shape, thereby avoiding loosening of the connection and increasing the stability of the connection;

[0074] Furthermore, an anchor nut 32 is provided at one end of the anchor plate 311 away from the tensioning part 2, and the anchor nut 32 is connected to the steel rod 1; a second spiral rib 6 is provided at one end of the anchor plate 311 facing the tensioning part 2, and the connection between the anchor nut 32 and the steel rod 1 can effectively apply the anchoring force, ensuring that the steel rod 1 is fully fixed during the tensioning process. The tight connection between the anchor nut 32 and the anchor plate 311 can enhance the stability of the overall anchoring part 3, prevent loosening or displacement due to external forces, and ensure that the mechanical properties of the steel rod 1 are maintained; the design of the second spiral rib 6 helps to evenly disperse the local force applied to the anchor plate 311 and reduce stress concentration. Through the arrangement of the second spiral rib 6, the force borne by the anchoring part 3 can be effectively transmitted to a wider area through the second spiral rib 6, thereby reducing the uneven force on the anchor plate 311 and improving the reliability of the entire steel rod structure. Figure 1 and Figure 5 shown.

[0075] In one or several embodiments, a second washer 10 is provided between the anchor nut 32 and the anchor plate 31. The second washer 10 can effectively disperse the local pressure exerted by the anchor nut 32 on the anchor plate 31, thereby avoiding uneven force on the anchor plate 31 due to pressure concentration, thereby improving the stability and uniformity of the entire steel rod structure.

[0076] Example 2

[0077] This embodiment 2 is a method for manufacturing an intelligent sensing steel rod structure in embodiment 1.

[0078] like Figure 7 The manufacturing method of the intelligent sensing steel rod shown is used to manufacture an intelligent sensing steel rod structure of Example 1, and the method comprises:

[0079] The outer surface of the steel rod 1 is processed to form grooves 11 and reinforcing ribs 7;

[0080] A plurality of fiber grating sensors 12 are respectively encapsulated in two grooves 11, and adjacent fiber grating sensors 12 in one groove 11 are connected in series (herein, the series connection refers to that two adjacent fiber grating sensors in the same groove 11 are connected and extended by connection);

[0081] An anchoring portion 3 is arranged at one end of the steel rod 1, and the anchoring portion 3 is arranged at one end of the arch foot joint section under construction;

[0082] A tensioning part 2 is arranged at the other end of the steel rod 1, and the tensioning part 2 is arranged at the other side of the arch foot joint section under construction and is arranged opposite to the anchoring part 3;

[0083] The steel rod 1 is tensioned by the tensioning part 2, and after the tensioning is completed, the tensioning part 2 is fixed to complete the manufacturing.

[0084] In one or more embodiments, Figure 4 The stress monitoring of the steel bar 1 in the axial direction shown includes:

[0085] Aαcosθ=A1α1+A2α2;

[0086] Where: α is the stress in the axial direction of the steel rod; α1 is the stress of the fiber Bragg grating sensor; α2 is the stress along the double helix groove; A is the cross-sectional area of ​​the steel rod; A1 is the cross-sectional area of ​​the fiber Bragg grating sensor; A2 is the cross-sectional area of ​​the steel rod along the normal plane of the double helix; θ is the angle between the double helix and the steel rod.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A steel bar structure, characterized in that: The invention comprises a steel rod (1), wherein a groove (11) is provided on the outer wall of the steel rod (1), wherein the groove (11) is arranged in a double helix shape along the length direction of the steel rod (1) with the axis of the steel rod (1) as the center line, and wherein the groove (11) is used to set a fiber optic grating sensor (12), and the fiber optic grating sensor (12) is used to monitor the stress of the steel rod (1) in the axial direction.

2. A steel bar structure according to claim 1, characterized in that: The steel rod (1) comprises a rod body (13) and a first large head end (16), wherein the first large head end (16) is connected to one end of the rod body (13), and a second large head end (17) is provided at one end of the rod body (13) away from the first large head end (16). A first outward expansion section (14) is provided between the rod body (13) and the first large head end (16), and a second outward expansion section (15) is provided between the rod body (13) and the second large head end (17).

3. A steel bar structure according to claim 2, characterized in that: The outer wall of the steel rod (1) is provided with reinforcing ribs (7), and the reinforcing ribs (7) are arranged in a spiral shape with the axis of the steel rod (1) as the center line.

4. A method for manufacturing a prestressed steel bar, characterized in that: Using a steel bar structure as claimed in any one of claims 2 to 3, the method comprises: Processing the outer surface of the steel rod (1) to form grooves (11) and reinforcing ribs (7); A plurality of fiber grating sensors (12) are respectively encapsulated in two grooves (11), and adjacent fiber grating sensors (12) in one groove (11) are connected in series; An anchoring portion (3) is arranged at one end of the steel rod (1), and the anchoring portion (3) is arranged at one end of the arch foot joint section under construction; A tensioning part (2) is arranged at the other end of the steel rod (1), and the tensioning part (2) is arranged at the other side of the arch foot joint section under construction; Complete manufacturing.

5. The method for manufacturing a prestressed steel bar according to claim 4, characterized in that: The tensioning portion (2) is connected to the steel rod (1), and the anchoring portion (3) is connected to the steel rod (1) and is arranged at an end away from the tensioning portion (2).

6. The method for manufacturing a prestressed steel bar according to claim 5, characterized in that: The tensioning portion (2) comprises a tensioning pad (21), and the tensioning pad (21) is located at one end of the tensioning portion (2) close to the anchoring portion (3). A first conical hole (211) is provided on the tensioning pad (21), and the first conical hole (211) is adapted to the first outward expansion section (14). The tensioning pad (21) is connected to the steel rod (1) via the first conical hole (211).

7. The method for manufacturing a prestressed steel bar according to claim 6, characterized in that: The tensioning pad (21) is provided with a first spiral rib (5) at one end facing the anchoring portion (3), and the tensioning pad (21) is provided with a tensioning nut (22) at one end away from the anchoring portion (3), and the tensioning nut (22) is connected to the steel rod (1).

8. The method for manufacturing a prestressed steel bar according to claim 7, characterized in that: The anchoring portion (3) comprises an anchoring pad (31), the anchoring pad (31) is provided with a second conical hole (311), the second conical hole (311) is adapted to the second outward expansion section (15), and the anchoring pad (31) is connected to the steel rod (1) via the second conical hole (311).

9. The method for manufacturing a prestressed steel bar according to claim 8, characterized in that: An anchor nut (32) is provided at one end of the anchor plate (31) away from the tensioning portion (2), and the anchor nut (32) is connected to the steel rod (1); and a second spiral rib (6) is provided at one end of the anchor plate (31) facing the tensioning portion (2).

10. The method for manufacturing a prestressed steel bar according to claim 9, characterized in that: The tensioning portion (2) is detachably connected to a waterproof cover (4).

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