Precast concrete pole

Abstract

The invention relates to a prefabricated concrete pole, the part, buried underground, of the prefabricated concrete pole comprises conductive concrete, and the conductive concrete comprises, by mass, 14-18 parts of cement, 22-34 parts of sand, 30-42 parts of gravel, 10-18 parts of water and 12-15 parts of conductive filler; the conductive filler comprises the following components in parts by mass: 20-25 parts of graphite, 5-10 parts of carbon fibers, 50-65 parts of steel slag and 5-15 parts of copper-plated steel fibers; the lightning protection performance is excellent, and the resistivity of soil near the grounding foundation is effectively reduced; the conductive chassis can integrally reduce the resistivity of soil around the lightning protection pole, the grounding foundation does not need to be provided with a radial grounding body, the excavation area needed by construction is greatly reduced, and the construction cost can be reduced by 30%. Compared with a traditional steel grounding body, the conductive concrete is made of graphite, steel slag, carbon fibers, copper-plated steel fibers and other materials, the service life of the electric pole can be greatly prolonged due to the excellent mechanical property and corrosion resistance of the conductive concrete, and the follow-up maintenance cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of concrete poles, and in particular to a prefabricated concrete pole. Background Art

[0002] Lightning protection and grounding of distribution lines are important components of various power facilities. They can effectively prevent electric shock, lightning strikes and strong electrical interference, and ensure the safety of equipment and personnel.

[0003] The traditional design and construction scheme for the natural grounding foundation of power distribution line towers is generally to bury a metal grounding body in the grounding foundation, such as the "lightning protection pole" disclosed in patent announcement number CN106639494A, in which the lightning rod and the grounding device are electrically connected through a grounding wire; as the line operation time increases, the metal grounding body will experience problems such as rust and aging, and the resistivity will increase, which cannot meet the standard requirements for the foundation pile grounding resistance.

[0004] Therefore, concrete made of conductive materials has emerged. Conductive concrete is a special concrete that uses conductive materials to partially or completely replace ordinary aggregates in concrete and has specified electrical properties and certain mechanical properties. The resistivity of ordinary concrete is generally 10 4 ~10 7 Ω·m range, conductive concrete is made by adding conductive materials to ordinary concrete, and the resistivity can reach 10 3 Ω·m or less, for example, the composite conductive elementary concrete disclosed in publication number CN1552657A uses carbonaceous materials, fibrous or shaving metal materials as conductive materials to prepare the composite conductive elementary concrete, so that the composite conductive elementary concrete has a certain strength and good conductivity.

[0005] However, the electric poles in the prior art are usually made of a whole concrete or conductive concrete. The electric pole made of a whole concrete has poor conductivity; and the electric pole made of a whole conductive concrete is easy to cause electric shock and personal injury in thunderstorm weather. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides a precast concrete pole to solve the above problems.

[0007] The present invention provides the following technical solutions:

[0008] A precast concrete pole, wherein the part of the precast concrete pole buried underground comprises conductive concrete, wherein the conductive concrete comprises, by weight: 14 to 18 parts of cement, 22 to 34 parts of sand, 30 to 42 parts of crushed stone, 10 to 18 parts of water and 12 to 15 parts of conductive filler;

[0009] The conductive filler comprises, by mass, 20 to 25 parts of graphite, 5 to 10 parts of carbon fiber, 50 to 65 parts of steel slag and 5 to 15 parts of copper-plated steel fiber.

[0010] Preferably, a lightning rod is installed at the upper end of the precast concrete pole, and a conductive chassis is connected to the lower end of the precast concrete pole via a connecting member, and the conductive chassis is buried underground.

[0011] Preferably, the connecting member includes a steel plate, a through bolt, an angle steel and a U-shaped ring embedded in the conductive chassis, the through bolt is fixed to the lower part of the precast concrete pole, and the end of the through bolt and the U-shaped ring are connected by the angle steel.

[0012] Preferably, an open groove is reserved at the lower portion of the precast concrete pole for the through bolt to pass horizontally.

[0013] Preferably, the steel cage of the precast concrete pole includes spiral bars, inner steel hoops and main bars, the spiral bars are spirally wound around the outer walls of multiple main bars along the axial direction of the precast concrete pole, and multiple groups of inner steel hoops are evenly arranged on the inner walls of multiple main bars along the axial direction of the precast concrete pole.

[0014] Preferably, the spiral ribs are connected with connecting bolts extending to above the top of the precast concrete pole, and the lightning rod is fixed to the top of the precast concrete pole by the connecting bolts.

[0015] Preferably, the precast concrete pole is divided into a plurality of partitions along its height direction, each of the partitions is provided with a corresponding indicator block, and the indicator block changes color at high temperature.

[0016] Preferably, the surface of the indicator block is coated with an irreversible temperature-variable ink layer, which will undergo an irreversible change in color when heated after being struck by lightning, thereby facilitating identification by operators.

[0017] Preferably, multiple groups of indicator blocks corresponding to the same isolation cavity are arranged in a line on a movable plate along the direction of gravity, and the movable plate is slidably connected to the guide rail along the direction of gravity. The movable plate is provided with fuses, and the fuses are electrically connected to the indicator blocks one by one, and the spiral ribs are connected with a conductive strip extending to contact the lowest fuse.

[0018] Preferably, the movable plate and the guide rail are fitted in a slow sliding manner.

[0019] The present invention has the following beneficial technical effects:

[0020] The present invention has excellent lightning protection performance and can effectively reduce the soil resistivity near the grounding foundation; the conductive chassis can reduce the soil resistivity around the lightning protection pole as a whole, and the grounding foundation no longer needs to be equipped with radial grounding bodies, which greatly reduces the excavation area required for construction and can reduce the construction cost by 30%.

[0021] Compared with traditional steel grounding electrodes, this conductive concrete uses materials such as graphite, steel slag, carbon fiber, and copper-plated steel fiber. Its excellent mechanical properties and anti-corrosion capabilities can greatly extend the service life of the poles and reduce subsequent maintenance costs.

[0022] The conductive lower section of the concrete pole is buried in the soil and is less susceptible to salt spray corrosion, making full use of its conductivity to improve grounding performance; the non-conductive upper section of the concrete pole is exposed to the air, and the use of non-conductive concrete can reduce the impact of salt spray corrosion in the air on the strength of the pole. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the arrangement structure of the indicator blocks on the precast concrete pole of the present invention;

[0025] Figure 3 It is a schematic diagram of the coordination of multiple indicator blocks, fuses and conductive strips of the present invention.

[0026] The reference numerals in the figure are:

[0027] 1. Lightning rod; 2. Connecting bolts; 3. Spiral reinforcement; 4. Inner steel hoop; 5. Main reinforcement; 6. Concrete; 7. Steel plate; 8. U-shaped ring; 9. Through bolt; 10. Angle steel; 11. Conductive chassis; 12. Partition part; 13. Indicator block; 14. Movable plate; 15. Guide rail; 16. Fuse; 17. Conductive strip. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiment 1:

[0030] A precast concrete pole, comprising a steel cage, conventional C40 concrete and conductive concrete, is precast in a factory, such as Figure 1 As shown:

[0031] Precast concrete poles are set on the ground with the upper section made of conventional C40 concrete. Non-conductive concrete is used to make the precast concrete poles on the ground non-conductive. Precast concrete poles exposed to the air can reduce the impact of salt spray corrosion in the air on the strength of precast concrete poles. At the same time, it can effectively avoid electric shock and personal injury caused by touching the concrete of the poles above the ground in thunderstorms;

[0032] The lower section of the precast concrete pole is made of conductive concrete that can conduct electricity and is set underground. It is less susceptible to salt spray corrosion, but its conductivity is fully utilized to improve the grounding performance.

[0033] The steel cage includes spiral reinforcement 3, inner steel hoops 4 and main reinforcement 5, which are woven according to the structural schematic diagram. Multiple main reinforcements 5 are arranged in a circular array. The spiral reinforcement 3 is spirally wound along the axial direction of the precast concrete pole and welded to the outer walls of the multiple main reinforcements 5. Multiple groups of inner steel hoops 4 are evenly arranged along the axial direction of the precast concrete pole and welded to the inner walls of the multiple main reinforcements 5.

[0034] The lightning rod 1 and the connecting bolt 2 are combined into a lightning protection device. The lower end of the connecting bolt 2 extends into the precast concrete pole and is connected to the spiral reinforcement 3. The lightning rod 1 is fixed to the top of the precast concrete pole through the upper end of the connecting bolt 2.

[0035] An open slot is reserved at the lower end of the precast concrete pole; the connecting member includes a steel plate 7, a through bolt 9, an angle steel 10 and a U-shaped ring 8. Two U-shaped rings 8 are precast in the conductive chassis 11, and the through bolt 9 passes through the precast concrete pole horizontally through the open slot; the lower end of the steel plate 7 is sleeved on the outer wall of the U-shaped ring 8, and the upper end of the steel plate 7 is fixed to the end of the through bolt 9 through a nut; thereby, the lower end of the precast concrete pole is fixed to the top of the conductive chassis 11 through the connecting member. The U-shaped ring 8 is precast in the conductive chassis 11 and connected to the steel plate 7, thereby connecting the entire precast concrete pole.

[0036] A groove matching the lower end of the precast concrete pole is provided on the top of the conductive chassis 11 , so as to facilitate the connection between the lower end of the precast concrete pole and the conductive chassis 11 .

[0037] The connecting bolt 2 is prefabricated on the spiral reinforcement 3 at the top of the steel cage, and the upper end of the connecting bolt 2 extends above the top of the prefabricated concrete pole and is finally connected to the lightning rod 1 to form a lightning protection circuit from the lightning rod 1 to the conductive chassis 11.

[0038] The lightning rod 1 is connected to the precast concrete pole through the connecting bolt 2; the precast concrete pole is connected to the conductive chassis 11 through the connecting member, and finally a lightning current discharge circuit is formed from the lightning rod 1 through the precast concrete pole to the conductive chassis 11 and connected to the ground.

[0039] The conductive concrete includes, by mass, 14-18 parts of cement, 22-34 parts of sand, 30-42 parts of crushed stone, 10-18 parts of water and 12-15 parts of conductive filler; the conductive filler includes, by mass, 20-25 parts of graphite, 5-10 parts of carbon fiber, 50-65 parts of steel slag and 5-15 parts of copper-plated steel fiber.

[0040] Graphite has good electrical conductivity. Adding it to cement can make concrete conductive. Graphite can improve the durability of concrete and reduce cracks and wear.

[0041] Carbon fiber has extremely high strength and elastic modulus. Adding it to cement can significantly improve the tensile strength and toughness of concrete and reduce the occurrence of cracks.

[0042] Adding steel slag to concrete can not only improve its strength and toughness, but also the steel slag contains a large amount of CaO and Fe2O3 solid solution. The effect of metal oxides such as Fe2O3 on improving the electrical conductivity of concrete cannot be ignored.

[0043] Ordinary steel fibers are prone to rust after long-term use, resulting in reduced conductivity and concrete strength. Copper-plated steel fibers can improve their fracture toughness and deformation capacity, resist the effects of chemical corrosion such as acid, alkali, and salt, and improve the durability of concrete. It can also improve the bonding performance between steel fibers and concrete.

[0044] Adding copper-plated steel fibers to concrete can not only improve the electrical conductivity of concrete, but its own high-strength characteristics enable concrete to effectively disperse and transfer loads when subjected to external forces, thereby improving the bearing capacity of concrete. The addition of steel fibers can also reduce pores and cracks inside the concrete, improve the concrete's impermeability, and prevent the intrusion of moisture and harmful substances.

[0045] The concrete pole material of the present invention comprises raw materials including: 14-18 parts by mass of cement, 22-34 parts by mass of sand, 30-42 parts by mass of crushed stone, 10-18 parts by mass of water, and 12-15 parts by mass of conductive filler. The conductive filler comprises: 20-25 parts of graphite, 5-10 parts of carbon fiber, 50-65 parts of steel slag, and 5-15 parts of copper-plated steel fiber.

[0046] Conductive concrete with conductive fillers added will have relatively poor salt spray corrosion resistance. The part buried underground is relatively less susceptible to salt spray corrosion than the part exposed to air. However, its conductivity is fully utilized to improve the grounding performance.

[0047] Embodiment 2: includes all the contents of Embodiment 1, except that Figure 2 As shown:

[0048] The precast concrete pole is divided into several partitions 12 along its length direction. The outer wall of the precast concrete pole is provided with an indicator block 13, which is connected to the spiral rib 3. Each partition 12 is provided with an indicator block 13. The surface of the indicator block 13 is coated with an irreversible temperature-changing ink layer.

[0049] When lightning occurs, the lightning rod 1 passes through the prefabricated concrete pole (mainly composed of the spiral reinforcement 3 of the steel cage) to the conductive chassis 11 and is connected to the ground, forming a lightning current discharge circuit. The indicator block 13 changes color after being heated after being struck by lightning.

[0050] By observing the color of the indicator blocks 1 at various heights, the corrosion condition of the steel cage inside can be roughly assessed.

[0051] Embodiment 3: includes all the contents of Embodiment 2, except that, as shown in Example 3:

[0052] Each partition 12 has multiple groups of indicator blocks 13, which are arranged in a line on a movable plate 14 along the direction of gravity. The movable plate 14 is provided with multiple fuses 16 arranged in a line along the direction of gravity. The fuses 16 correspond to and are connected to the indicator blocks 13 one by one. The movable plate 14 slides linearly along the direction of gravity on the guide rail 15 relatively. The spiral rib 3 is connected with a conductive strip 17, and the free end of the conductive strip 17 extends to the bottom of the movable plate 14.

[0053] Under the action of gravity, the lowest fuse 16 is connected to the top of the conductive strip 17. When lightning occurs, the current of the spiral reinforcement 3 of the steel cage is transmitted to the indicator block 13 through the conductive strip 17 and the fuse 16. The indicator block 13 changes color after being heated by lightning, and the fuse 16 melts due to heat overload.

[0054] Then, under the action of gravity, the movable plate 14 moves downward relative to the guide rail 15 , so that another group of fuses 16 closest to the blown fuse 16 overlaps the top of the conductive strip 17 .

[0055] Furthermore, an elastic member is connected between the movable plate 14 and the guide rail 15, and the movable plate 14 is pushed to move downward by the elastic member.

[0056] Through the above arrangement, the corrosion of the steel bars in the inner partition 12 of the precast concrete pole can be judged by the color changes of the multiple groups of indicator blocks 13 in the same partition 12 when struck by lightning.

[0057] The above-mentioned embodiments only express the specific implementation of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A precast concrete pole, characterized in that: The part of the precast concrete pole buried underground includes conductive concrete, which includes, by mass, 14 to 18 parts of cement, 22 to 34 parts of sand, 30 to 42 parts of crushed stone, 10 to 18 parts of water and 12 to 15 parts of conductive filler; The conductive filler comprises, by mass, 20 to 25 parts of graphite, 5 to 10 parts of carbon fiber, 50 to 65 parts of steel slag and 5 to 15 parts of copper-plated steel fiber.

2. A precast concrete pole according to claim 1, characterized in that: A lightning rod (1) is installed on the upper end of the precast concrete pole, and a conductive chassis (11) is connected to the lower end of the precast concrete pole via a connecting member, and the conductive chassis (11) is buried underground.

3. The precast concrete pole according to claim 2, characterized in that: The connecting component comprises a steel plate (7), a through bolt (9), an angle steel (10) and a U-shaped ring (8) pre-buried in a conductive chassis (11); the through bolt (9) is fixed to the lower part of a precast concrete pole; the end of the through bolt (9) and the U-shaped ring (8) are connected via the angle steel (10).

4. The precast concrete pole according to claim 3, characterized in that: An open slot is reserved at the lower part of the precast concrete pole for the through-bolt (9) to pass through horizontally.

5. The precast concrete pole according to claim 2, characterized in that: The steel cage of the precast concrete pole comprises spiral bars (3), inner steel hoops (4) and main bars (5), wherein the spiral bars (3) are spirally wound around the outer walls of a plurality of main bars (5) along the axial direction of the precast concrete pole, and a plurality of groups of inner steel hoops (4) are evenly arranged on the inner side walls of the plurality of main bars (5) along the axial direction of the precast concrete pole.

6. The precast concrete pole according to claim 5, characterized in that: The spiral ribs (3) are connected to connection bolts (2) extending to the top of the precast concrete pole, and the lightning rod (1) is fixed to the top of the precast concrete pole via the connection bolts (2).

7. The precast concrete pole according to claim 5, characterized in that: The precast concrete pole is divided into a plurality of partitions (12) along its height direction, each of the partitions (12) is provided with a corresponding indicator block (13), and the indicator block (13) changes color at high temperature.

8. The precast concrete pole according to claim 7, characterized in that: The surface of the indicator block (13) is coated with an irreversible temperature-variable ink layer.

9. The precast concrete pole according to claim 8, characterized in that: A plurality of groups of indicating blocks (13) corresponding to the same isolation cavity (12) are arranged in a line on a movable plate (14) along the direction of gravity. The movable plate (14) is slidably connected to a guide rail (15) along the direction of gravity. The movable plate (14) is provided with a fuse (16). The fuse (16) is electrically connected to the indicating block (13) in a one-to-one correspondence. The spiral rib (3) is connected with a conductive strip (17) extending to contact the lowest fuse (16).

10. The precast concrete pole according to claim 9, characterized in that: The movable plate (14) and the guide rail (15) are fitted in a slow sliding manner.

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