CN203769404U - High-intensity post-tensioning reinforced concrete pole - Google Patents

Abstract

The utility model relates to a high-strength post-tensioning reinforced concrete electric pole. The technical problem to be solved by the utility model is to provide high-strength post-tensioned reinforced concrete poles to ensure the safety and reliability of the poles. The technical solution to solve this problem is: a high-strength post-tensioned reinforced concrete pole, including a hollow conical concrete body, a steel cage embedded in the side wall of the concrete body, and a coaxial pole located at both ends of the concrete body. Two disc-shaped prestressed anchor steel plates are arranged; the reinforcement cage includes a set of prestressed steel rods for concrete that are evenly distributed around the axis of the concrete body, and a set of non-prestressed steel rods that are arranged alternately with the prestressed steel rods and evenly distributed around the axis of the concrete body. Stressed main reinforcement, an even number of short reinforcements distributed axisymmetrically with the axis of the concrete body as the center, a group of inner steel hoops that are welded evenly along the axial intervals inside the cage surrounded by non-prestressed main reinforcements and short reinforcements, and spirally wound Spiral reinforcement on the outside of the cage. The utility model is used for electric poles in power transmission and distribution lines.

Description

High-strength post-tensioned reinforced concrete poles

technical field

The utility model relates to a concrete electric pole, in particular to a high-strength post-tensioned reinforced concrete electric pole, which is mainly suitable for power transmission and distribution lines.

Background technique

Reinforced concrete poles are used in the structure of substations and the supporting function of transmission and distribution lines. According to their uses, they are divided into straight poles, branch poles, corner poles, tension poles and terminal poles. They are still widely used in power distribution lines . In recent years, the innovation and invention of concrete poles are mainly to improve the structure and increase the strength level of concrete, but the force applied to the prestressed tendons is applied before the concrete is centrifugally formed, that is, the pretensioning production process, so in principle it's the same. Due to the limitations of the pretensioning process, for example, prestressed perforated slabs, which were widely used in civil buildings in the last century, were constructed by the pretensioning method, and the bridge slabs in the current reinforced concrete bridges are produced by the post-tensioning process to be more load-bearing. At present, the land resources in small and medium-sized cities are in short supply, the corridors of power distribution lines are becoming more and more tense, and it is difficult to popularize cable lines due to the high cost, and the concrete poles used for power transmission lines are more than 18m and need to be equipped with square guy wires. Concrete poles are rarely used in power lines. To save cost and reduce land occupation, the only way to develop multi-circuit lines is to develop in the direction of multi-circuits. It is like erecting four-circuit lines on poles. In this way, the bending strength of poles must be improved, while concrete power lines Compared with steel pipe poles and iron towers, poles are economical and easy to maintain later, and have significant advantages in application in power distribution lines.

Application number 200710027089.0, patent name "prestressed concrete pole and its production process" (notification number CN101029540A) Chinese invention patent application, discloses a prestressed concrete pole, in the steel cage by the main bar of equal length, non- Prestressed tendons, vertical rings distributed in the longitudinal direction, steel bars wrapped with spiral bars outside to form a cage, assembled into a steel mold, poured into concrete slurry, closed the mold, stretched the main bars, and steamed after centrifugal molding. demoulding. The invention of the above-mentioned literature application lies in that the prestressed tendon in the main reinforcement adopts PC steel rod, Fptk=1420Mpa, and the steel structure and concrete strength have been innovated, but it is still the current traditional pretensioning process, which is subject to the congenital defects of the pretensioning production process , and the limitation of the concrete gripping force, the improvement of the strength and bending moment of the pole is limited.

Application number 200610116733.7, patent name "Concrete for high-strength reinforced concrete pole with large bending moment" (notification number CN1958262A) Chinese invention patent application, discloses a concrete from C50 to C60, using prestressed The structure composed of main steel bars, non-prestressed main steel bars, steel hoops and spiral bars is produced according to the conventional concrete pole production process. Among them, the bending moment of the 24-meter concrete pole is 240 kn.m, the bending moment of the 27-meter concrete pole is 270 kn.m, and the bending moment of the 30-meter concrete pole is 300 kn.m. The invention of the above-mentioned document application and the aforementioned application 200710027089.0 both belong to the traditional conventional prestressing and pretensioning production process. The prestressing main reinforcement material used in both is the same PC steel rod, and the tensile strength is 1420n/mm ² . At present, concrete poles are widely used in power distribution lines, and power distribution lines are mainly used for poles below 18 meters. The bending moment of the 24-meter concrete pole mentioned in the above literature is 240kn.m, and the bending moment of the 27-meter concrete pole is 270 kn.m, the bending moment of a 30-meter concrete pole is 300 kn.m. Converted to the 18-meter pole, and then according to the "Ring Concrete Pole Standard" GB/4623-2006 National Standard GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 When the bar standard inspection bending moment L2=2.5 meters, the standard inspection bending moment is 155kn..m. And this value is equivalent to GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 GB/4623-2006 national standard 18 meters electric pole tip diameter 350mm standard test bending moment Q grade value is 152.5kn.m, I grade value is 176.75kn.m, far from the national standard The strongest grade, Q grade 228.75kn.m, still has a difference of three grades, and it has not reached the bending moment value of the strongest grade that exceeds the national standard. The 24m, 27m, and 30m concrete poles used in power transmission lines above 110kV must have square guy wires. The biggest disadvantage of poles with square guy wires is the land occupation. Land resources are in short supply. Currently, power transmission lines are generally replaced by relatively occupied land. Fewer iron towers and steel pipe poles. The distribution line is mainly used below 18 meters, and the straight pole can solve the stability problem of the pole through deep burial. Therefore, it is still common to use concrete poles for distribution lines.

Contents of the invention

The technical problem to be solved by the utility model is to break through the traditional production process of the pre-tensioning method used in the existing prestressed electric poles, and provide a high-strength post-tensioned reinforced concrete electric pole to improve the strength, prestressed performance, and elasticity of the electric pole. The recovery ability, instantaneous bearing capacity and operating life further ensure the safety and reliability of the pole.

The technical solution adopted by the utility model is: a high-strength post-tensioned reinforced concrete pole, which includes a concrete body in the shape of a hollow truncated cone as a whole, a steel cage embedded in the side wall of the concrete body, and a Two disc-shaped prestressed anchor steel plates coaxially arranged at the ends, characterized in that: on the prestressed anchor steel plate, a circle of circularly arranged holes is evenly distributed with its center as the center, and the two prestressed anchor steel plates The holes above are arranged in one-to-one correspondence; the reinforcement cage includes a set of prestressed steel rods for concrete that are evenly distributed around the axis of the concrete body, and a group of non-prestressed steel rods that are arranged alternately with the prestressed steel rods and evenly distributed around the axis of the concrete body. The main reinforcement, an even number of short reinforcements distributed axisymmetrically with the axis of the concrete body as the center, a group of inner steel hoops welded uniformly along its axial interval inside the cage surrounded by the non-prestressed main reinforcement and short reinforcements, and spiral winding The spiral reinforcement on the outside of the cage, wherein the two ends of the prestressed steel rod pass through the corresponding two holes on the two prestressed anchor steel plates, and the anchor ends are limited by the integrally formed piers or threaded nuts. It is located on the outer surface of one of the prestressed anchor steel plates, and the tensioned end is limited to the outer surface of the other prestressed anchor steel plate by threaded nuts after being stretched. After tension, each prestressed steel rod is relative to the axis of the concrete body of the same taper.

The prestressed anchoring steel plate is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12-20mm. The outer side is processed with a shoulder clip protruding from the pole body, and its thickness is half of the thickness of the prestressed anchoring steel plate.

The prestressed steel rod adopts a prestressed steel rod for unbonded smooth concrete with a tensile strength value of 1570N/mm ² , a relaxation rate of 1000h ≤ 2.5%, and a diameter of 9-12mm, and a plastic jacket is coaxially sleeved outside it. And between the two is filled with anti-corrosion grease.

Both the non-prestressed main reinforcement and the short reinforcement adopt HRB500 ordinary steel reinforcement, the tensile strength is 435N/mm ² , the compressive strength is 410 N/mm ² , and the diameter is 12mm or 14mm; the short reinforcement is arranged symmetrically in stages, each level The number of short bars is an even number, the length is the same, and they are arranged symmetrically with the axis of the reinforcement cage as the central axis. The length difference between two adjacent short bars is 2.5m.

The inner steel hoop is formed by bending steel bars with a diameter of 6 mm, and the axial distance between two adjacent inner steel hoops is 500 mm; the diameter of the spiral steel bar is 4 mm; the taper of each prestressed steel rod relative to the axis of the concrete body and The pole taper is 1:75±5.

High-strength post-tensioned reinforced concrete pole, which will include at least two pole sections when it is more than 15m; , and two disc-shaped prestressed anchoring steel plates arranged coaxially at both ends of the concrete body, characterized in that: on the prestressed anchoring steel plate, a circle of circularly arranged holes is evenly distributed with its center as the center of the circle, And the holes on the two prestressed anchor steel plates are arranged in one-to-one correspondence; the reinforcement cage includes a group of prestressed steel rods for concrete that are evenly distributed around the axis of the concrete body, and a group of prestressed steel rods that are arranged alternately with the A group of non-prestressed main reinforcements uniformly distributed along the axis, an even number of short reinforcements distributed symmetrically around the axis of the concrete body, and uniformly welded at intervals along the axial direction inside the cage surrounded by non-prestressed main reinforcements and short reinforcements The inner steel hoop, and the spiral steel bars spirally wound on the outside of the cage, wherein the two ends of the prestressed steel rod respectively pass through the two corresponding holes on the two prestressed anchor steel plates, and the anchor ends pass through the integrally formed pier The nuts connected by head or threads are limited to the outer surface of one of the prestressed anchoring steel plates, and the nuts connected by threads are limited to the outer surface of the other prestressed anchoring steel plate after the tension end is stretched. The taper of the steel rods relative to the axis of the concrete body is the same; an inner flange is installed at the butt end of each pole section, and each pole section is connected by inner flange bolts to form a whole.

The inner flange includes a cylindrical inscribed steel ring plate coaxially welded on the outer surface of the prestressed anchor steel plate at the butt end, a group of rib plates uniformly welded to the periphery of the inscribed steel ring plate in the radial direction, welded to The butt steel plate arranged parallel to and coaxial with the prestressed anchor steel plate above the inner steel ring plate and the stiffener plate, and two steel bars wrapped around the outer side of the stiffener plate and welded thereto.

The prestressed anchoring steel plate is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12-20mm. The outer side is processed with a shoulder clip protruding from the pole body, and its thickness is half of the thickness of the prestressed anchoring steel plate.

The prestressed steel rod adopts a prestressed steel rod for unbonded smooth concrete with a tensile strength value of 1570N/mm ² , a relaxation rate of 1000h ≤ 2.5%, and a diameter of 9-12mm, and a plastic jacket is coaxially sleeved outside it. And between the two is filled with anti-corrosion grease.

Both the non-prestressed main reinforcement and the short reinforcement adopt HRB500 ordinary steel reinforcement, the tensile strength is 435N/mm ² , the compressive strength is 410 N/mm ² , and the diameter is 12mm or 14mm; the short reinforcement is arranged symmetrically in stages, each level The number of short bars is an even number, the length is the same, and they are arranged symmetrically with the axis of the steel cage as the central axis. The length difference between two adjacent short bars is 2.5m; the inner steel hoop is made of bent steel bars with a diameter of 6mm. The axial distance between two adjacent inner steel hoops is 500mm; the diameter of the spiral steel bar is 4mm; the taper of each prestressed steel rod relative to the axis of the concrete body and the taper of the electric pole are 1:75±5.

The beneficial effects of the utility model are: 1. The utility model adopts the post-tensioning process to produce the electric pole, which has higher strength and can be applied in the four circuits of the same pole of the high-strength power distribution line, and the tip diameter is reduced to make the electric pole more compact. It is suitable for construction, replacing large-diameter electric poles, straight steel pipe poles, and iron towers, and can save steel at the same time. 2. The poles produced by the post-tensioning process have better elastic recovery ability. After the test, when the bearing capacity of the pole reaches 200% of the allowable bending moment value of the pole, it can be recovered after losing the bearing capacity and the gap is closed. When the pole is stretched first, when the bearing capacity of the pole reaches 200% of the allowable bending moment value of the pole, it is difficult to close the gap after the bearing capacity is removed. The pole is stretched first and the retraction ability is limited after stretching due to the grip of the concrete. First stretch the pole, and its bearing capacity reaches 200% of the allowable bending moment value of the pole, which is equivalent to doing a destructive test. 3. Through the plastic jacket set outside the prestressed steel rod, a channel is formed during centrifugal molding, and the prestressed steel rod can freely expand and slide in the channel. When the prestressed steel rod rebounds, the entire pole retracts. The instantaneous bearing capacity of the pole is greatly improved to ensure that it will not cause destructive damage to the pole after overloading, so the post-tensioned pole has better safety and reliability, and the strength of the post-tensioned pole has been improved in a whole series , as the moment of inertia increases, the strength value exceeds the existing national standard value, and the greater it is. 4. The new concrete formula is adopted to make the concrete strength reach C100 level, and the infiltration of concrete fibers improves the problem of complicated local concrete stress under the anchor steel plate, improves the compression resistance, and fully exerts the role of large post-tensioning tension, and High-strength concrete has the characteristics of longer life than ordinary concrete, which improves the operating life of the pole. 5. The maintenance of the pole after the concrete is formed is naturally maintained throughout the whole process, and there is no steam pool maintenance link, which saves raw materials and reduces costs. 6. The prestressed main reinforcement adopts prestressed steel rods for unbonded smooth concrete with a tensile strength value of 1570N/mm ² , a relaxation rate of 1000h ≤ 2.5%, and a diameter of 9-12mm, which fully utilizes the high-strength prestressed steel rods. The tensile effect improves the prestressing performance. 7. The electric poles of ∮270mm×15m and ∮270mm×18m specifications of this utility model are suitable for the erection of LGJ-240/30 conductors of four-circuit distribution lines on the same pole, and the requirements of large bending moment straight poles with an average span of more than 50m can be It replaces the functions of straight steel pipe poles and narrow-base iron towers, is convenient for operation and maintenance, is economical and reliable, and is suitable for popularization and application in multi-circuit power distribution lines.

Description of drawings

Figure 1 is a combination diagram of the tension end rod tip and the sealing cap.

Figure 2 is a combination diagram of the rod root and the seal foot (steel rod and nut structure).

Figure 3 is a combination diagram of the rod root and the foot seal (steel rod pier head structure).

Figure 4 is a cross-sectional view of the reinforcement cage.

Fig. 5 is an assembly diagram of the whole single pole.

Figure 6 is a structural diagram of the connection between the butt end of the segmented pole (using nuts to limit the position) and the inner flange.

Figure 7 is a structural diagram of the connection between the segmented pole butt end (using pier head limit) and the inner flange.

Fig. 8 is a view along the line A-A of Fig. 7 .

Fig. 9 is a B-B arrow view of Fig. 7 .

Fig. 10 is a cross-sectional view of segmented electric poles.

Fig. 11 is a reinforcement diagram of the pole of embodiment 1∮190mm×12m.

Fig. 12 is a reinforcement diagram of the 6m upper section of the segmented electric pole of embodiment 2∮ 270mm×15m.

Fig. 13 is a reinforcement diagram of the 9m lower section of the segmented electric pole of embodiment 2∮270mm×15m.

Detailed ways

The tip diameter of the electric pole of the utility model follows the various specifications of the national standard from ∮190mm to ∮350mm. The length of the pole is 6m~15m, and the length of 15m and above can be manufactured in sections, which is convenient for transportation to meet the different needs of transmission and distribution lines and substation structures. There is a whole rod type as shown in Figure 5, and there are various specifications such as ∮190mm×10m, ∮190mm×12m, ∮190mm×13m, ∮230mm×13m, ∮270mm×13m, ∮310mm×13m, ∮350mm×13m, etc. There are two-stage poles with upper and lower sections, such as ∮190mm×15m, ∮230mm×15m, ∮270mm×15m, ∮270mm×18m, ∮270mm×24m, ∮270mm×27m, ∮310mm×15m, ∮350mm×15m. For 15m poles, it can be divided into upper section 6m and lower section 9m, ∮270mm×18m can be divided into upper section 9m and lower section 9m, ∮350mm×18m can be divided into upper section 9m and lower section 9m, as shown in Figure 10, between the upper section and the lower section The joints are connected by inner flange bolts.

Embodiment 1: As shown in Fig. 1-Fig. 5, this embodiment comprises the concrete body 8 that is hollow conical shape as a whole, the reinforcement cage that is embedded in this concrete body side wall, and is located at this concrete body two ends and coaxial Two disc-shaped prestressed anchor steel plates 1 are arranged. Six holes 15 are evenly distributed on the prestressed anchoring steel plate 1, and each hole 15 is arranged in a circle with the center of the prestressed anchoring steel plate 1 where it is located as the center of the circle, and the holes on the two prestressed anchoring steel plates 1 15 are arranged in one-to-one correspondence. The reinforcement cage includes six prestressed steel rods 3 for concrete that are evenly distributed around the axis of the concrete body 8, six non-prestressed main bars 4 that are arranged alternately with the prestressed steel rods 3 and evenly distributed around the axis of the concrete body 8, and six with a concrete body The 8 axis is the short ribs 5 distributed symmetrically to the central axis, a group of inner steel hoops 6 that are welded evenly along the axial intervals inside the cage surrounded by the non-prestressed main ribs 4 and the short ribs 5, and spirally wound around the cage. The spiral steel bar 7 (diameter 4mm) on the outside of the cage is described, wherein the two ends of the prestressed steel rod 3 respectively pass through the corresponding two holes 15 on the two prestressed anchor steel plates 1, and the anchor ends pass through the integrally formed piers. 20 or the threaded nut 2 is limited to the outer surface of one of the prestressed anchor steel plates 1, and the tensioned end is limited to the outer surface of the other prestressed anchor steel plate 1 by the threaded nut 2 after tensioning. The taper of each prestressed steel rod 3 relative to the axis of the concrete body 8 is the same (1:75). The short ribs 5 are divided into three levels, the length of two short ribs 5 is 9.5m, and the top of the short ribs is 2.5m away from the tip of the pole. The tip is 5m as the second-level short rib, and the length of the remaining two short ribs 5 is 4.5m. The distance from the top of the short rib is 7.5m to the pole tip. Arranged symmetrically about the central axis. Its reinforcement diagram is shown in Figure 11.

The prestressed anchoring steel plate 1 is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12-20mm, which is determined according to the tension value; Half of the thickness of the stress anchoring steel plate 1, the shoulder clip 23 protrudes from the rod body, that is, the diameter of the shoulder clip at the tip end of the rod is larger than the diameter of the rod tip, and the diameter of the shoulder clip at the root end of the rod is larger than the diameter of the rod root.

The prestressed steel rod 3 is a prestressed steel rod for unbonded smooth concrete with a tensile strength value of 1570N/mm ² , a relaxation rate of 1000h ≤ 2.5%, and a diameter of 10mm. A plastic jacket 21 is coaxially sleeved on the outside. And between the two is filled with anti-corrosion grease.

Both the non-prestressed main reinforcement 4 and the short reinforcement 5 are made of HRB500 ordinary steel bars, with a tensile strength of 435 N/mm ² , a compressive strength of 410 N/mm ² , and a diameter of 12 mm.

The inner steel hoop 6 is formed by bending a steel bar with a diameter of 6 mm, the axial distance between two adjacent inner steel hoops 6 is 500 mm, and the inner steel hoop double-jointed structure is adopted within a range of one meter from both ends The form is welded; The winding steel bar 7 is densely wound within a range of one meter from both ends.

The raw materials for the preparation of the concrete body 8 include cement, sand, gravel, water, fly ash, silica fume, water reducing agent, and concrete fiber, and the weight ratio of each component is 1:1.28~1.30:2.35~2.5:0.18 ~0.24: 0.08~0.1: 0.19~0.21: 0.04~0.06: 0.0018~0.002; its strength is C100. In this example, the cement is ordinary Portland cement of grade ≥52.5; the fineness modulus of the sand is 2.3~2.7, and the mud content is 0.25%; 5%, the compressive strength is not less than 120Mpa; the fly ash is the first-class standard fly ash, the silica fume particle size is 0.15~0.2μm; the water reducer is polycarboxylate pure SH with a concentration of 40%; the concrete fiber adopts The third-generation high-performance concrete fiber, the model is UF500 cellulosic fiber, and the monofilament fiber is 2.1 mm.

In order to prevent the end of the pole from being damaged by collision during transportation and construction, and to protect the exposed anchors such as the nut 2 and the prestressed steel rod 3, a prefabricated sealing cap 9 and a prefabricated sealing foot are respectively put on the pole tip and the pole root 11. The sealing cap 9 and the sealing foot 11 are prefabricated respectively according to the specifications of the pole tip and the pole root. They are made of reinforced concrete, the concrete strength is C40, the diameter of the sealing steel bar 10 is 8mm, and the diameter of the sealing foot steel bar 12 is 12mm. The diameter of the pole determines the inner diameter, the thickness of the edge is 50 mm, the insertion depth of the sealing cap 9 needs to cover the rod tip 65 mm, the bottom thickness of the sealing foot 11 is 120 mm, the depth of the sealing foot 11 is 100 mm in the root of the pole, and the prefabricated protective cap (seal foot and sealing cap) according to the corresponding specifications, put on the corresponding pole, and fill the protective cap with epoxy mortar 13 to cure.

The production technology of present embodiment pole is as follows:

1.1. Arrange a group of non-prestressed tendons distributed around its axis according to the size of the proposed pole (tip diameter ∮190mm, length 12m) and taper (1:75) (composed of six non-prestressed main tendons 4 and six short tendons 5 composition), the taper of each non-prestressed tendon relative to the axis of the proposed pole is 1:75; Steel hoops 6, and each inner steel hoop 6 is coaxially arranged, and the inner steel hoops are welded within a range of one meter from both ends; When arranging the prestressed anchoring steel plate 1 and the prestressed anchoring steel plate 1, the holes 15 are adjusted so that the connection line corresponding to the two holes 15 intersects with each non-prestressed main rib 4.

1.2. On the two prestressed anchor steel plates 1, insert a prestressed steel rod 3 for concrete into each corresponding two holes 15 (six prestressed steel rods are set up in this embodiment, and they are connected with the non-prestressed main reinforcement 4 Arranged alternately), and the anchoring end of the prestressed steel rod is anchored on the outer surface of one of the prestressed anchoring steel plates 1, and the tension end is threaded to connect a nut 2 that is tightly pressed against the outer surface of the other prestressed anchoring steel plate 1 to realize The prestressed anchor steel plate 1, the prestressed steel rod 3 and the cage are locked and formed, and at the same time, the taper of each prestressed steel rod 3 relative to the axis of the proposed pole is the same (1:75). As shown in Figure 3, for a prestressed steel bar 3 with a pier head 20 at one end and a threaded structure at the other end, the end with the pier head 20 is used as the anchoring end to be located on the outer surface of one of the prestressed anchoring steel plates 1, and then cut Remove the overcoat 21 at the end of the other end (tension end), and tighten the limit and the outer surface of another prestressed anchor steel plate 1 with a nut 2; Both ends are locked and fixed by nuts 2; in this embodiment, both ends are locked and fixed by nuts 2.

1.3. Spiral steel bars 7 with a diameter of 4 mm are continuously and densely wound round by round on the outer side of the cage body in a spiral winding manner, and densely wound within a range of one meter from both ends to form a steel bar cage.

1.4. Hoist the reinforcement cage obtained in step 1.3 into the pole steel mold base, clamp the shoulder clips 23 of the two prestressed anchor steel plates 1 into the grooves, and tighten the nuts 2 to ensure that each prestressed steel rod 3 is relatively The tapers of the electric poles are all the same, pour concrete slurry, clear the edge of the steel mold, close the upper cover of the steel mold, close the mold, tighten the mold clamping bolts of the steel mold, and tighten the nut 2 again, and the steel mold as a whole Hang it into the centrifuge, and the centrifuge gradually increases the speed, from low speed to medium speed and finally to 1050 rpm. After being centrifuged, it is lifted out, placed in balance, and demoulded after 3 days of natural curing, and then naturally cured for 21 days.

1.5. Implement tensioning at the tensioning end, lock the 3 tensioning ends of the prestressed steel rod through the tool anchor, and then use the hydraulic machine to expand the tensioning. The tension value is designed according to 70% of the tensile value of the prestressed steel rod 3. The above 6 The tension value of the prestressed steel rod 3 is 517.6KN. After reaching the tension design value, lock the nut 2, and leave half of the thread of the prestressed steel rod 3 elongated due to tension, and saw off the excess part.

The pole inspection bending moment obtained by the method of this embodiment reaches 69.4KN.m, and its strength is higher than that of the national standard ∮190mm×12m. The improvement of post-tensioning highlights its advantages even more.

Embodiment 2: As shown in Figure 1-4 and Figure 6-10, the electric pole of this embodiment is a ∮270mm×15m electric pole, which is formed by docking the upper 6m and lower 9m pole sections.

The 6m pole section of the upper section includes a hollow truncated concrete body 8 (taper 1:75), a steel cage embedded in the side wall of the concrete body, and two coaxially arranged two ends of the concrete body. A disc-shaped prestressed anchor steel plate 1, and an inner flange installed at the butt end (rod end). Eight holes 15 are evenly distributed on the prestressed anchoring steel plate 1, and each hole 15 is arranged in a circle with the center of the prestressed anchoring steel plate 1 where it is located as the center of the circle, and the holes on the two prestressed anchoring steel plates 1 15 are arranged in one-to-one correspondence. The reinforcement cage includes eight prestressed steel bars 3 for concrete that are evenly distributed around the axis of the concrete body 8, eight non-prestressed main bars 4 that are arranged alternately with the prestressed steel bars 3 and that are evenly distributed around the axis of the concrete body 8, and two Short ribs 5 distributed symmetrically around the axis of the concrete body 8, a group of inner steel hoops 6 that are uniformly welded at intervals along the axial direction inside the cage surrounded by non-prestressed main ribs 4 and short ribs 5, and spiral The spiral steel bar 7 (diameter 4mm) wound on the outside of the cage, wherein the two ends of the prestressed steel rod 3 respectively pass through the two corresponding holes 15 on the two prestressed anchor steel plates 1, and the anchor ends are integrally formed The pier head 20 or the threaded nut 2 is limited to the outer surface of one of the prestressed anchor steel plates 1, and the tension end is limited to the outer surface of the other prestressed anchor steel plate 1 by the threaded nut 2 after being stretched. , the taper of each prestressed steel rod 3 relative to the axis of the concrete body 8 after tensioning is the same (1:75). The length of the two short ribs 5 is 3.5m, that is, the top of the short ribs is 2.5m away from the pole tip, and the bottom end is in contact with the prestressed anchor steel plate 1 of the pole root, and the two short ribs 5 are centered on the axis of the proposed pole section Axisymmetric arrangement. Its reinforcement diagram is shown in Figure 12.

The inner flange includes a cylindrical inner ring plate 17 coaxially welded on the outer surface of the prestressed anchoring steel plate 1 at the butt end, and a set of stiffener plates 16 uniformly welded on the periphery of the inner ring plate in the radial direction , the butt steel plate 18 welded on the inner ring plate 17 and the stiffener plate 16, parallel and coaxial with the prestressed anchor steel plate 1, and two steel bars 19 wound on the outside of the stiffener plate 16 and welded thereto.

The prestressed anchoring steel plate 1 is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12-20mm, which is determined according to the tension value; Half of the thickness of the stress anchoring steel plate 1, the shoulder clip 23 protrudes from the rod body, that is, the diameter of the shoulder clip at the tip end of the rod is larger than the diameter of the rod tip, and the diameter of the shoulder clip at the root end of the rod is larger than the diameter of the rod root.

The prestressed steel rod 3 is a prestressed steel rod with a tensile strength of 1570N/mm ² , a relaxation rate of ≤2.5% in 1000h, and a diameter of 11mm for unbonded smooth concrete. , and filled with anti-corrosion grease between the two.

Both the non-prestressed main reinforcement 4 and the short reinforcement 5 are made of HRB500 ordinary steel reinforcement, with a tensile strength of 435N/mm ² , a compressive strength of 410 N/mm ² , and a diameter of 14mm.

The inner steel hoop 6 is formed by bending a steel bar with a diameter of 6 mm, the axial distance between two adjacent inner steel hoops 6 is 500 mm, and the inner steel hoop double-jointed structure is adopted within a range of one meter from both ends The form is welded; The winding steel bar 7 is densely wound within a range of one meter from both ends.

The raw materials for the preparation of the concrete body 8 include cement, sand, gravel, water, fly ash, silica fume, water reducing agent, and concrete fiber, and the weight ratio of each component is 1:1.28~1.30:2.35~2.5:0.18 ~0.24: 0.08~0.1: 0.19~0.21: 0.04~0.06: 0.0018~0.002; its strength is C100. In this example, the cement is ordinary Portland cement of grade ≥52.5; the fineness modulus of the sand is 2.3~2.7, and the mud content is 0.25%; 5%, the compressive strength is not less than 120Mpa; the fly ash is the first-class standard fly ash, the silica fume particle size is 0.15~0.2μm; the water reducer is polycarboxylate pure SH with a concentration of 40%; the concrete fiber adopts The third-generation high-performance concrete fiber, the model is UF500 cellulosic fiber, and the monofilament fiber is 2.1 mm.

In order to prevent the end of the pole from being damaged by collision during transportation and construction, and to protect the exposed anchors such as the nut 2 and the prestressed steel rod 3, a prefabricated sealing cap 9 and a prefabricated sealing foot are respectively put on the pole tip and the pole root 11. The sealing cap 9 and the sealing foot 11 are prefabricated respectively according to the specifications of the pole tip and the pole root. They are made of reinforced concrete, the concrete strength is C40, the diameter of the sealing steel bar 10 is 8mm, and the diameter of the sealing foot steel bar 12 is 12mm. The diameter of the pole determines the inner diameter, the thickness of the edge is 50 mm, the insertion depth of the sealing cap 9 needs to cover the rod tip 65 mm, the bottom thickness of the sealing foot 11 is 120 mm, the depth of the sealing foot 11 is 100 mm in the root of the pole, and the prefabricated protective cap (seal foot and sealing cap) according to the corresponding specifications, put on the corresponding pole, and fill the protective cap with epoxy mortar 13 to cure.

The structure of the 9m pole section of the lower section is basically the same as that of the 6m pole section of the upper section. The difference is that the reinforcement of the reinforcement cage is different. 9m and non-prestressed main reinforcement 4 and four short reinforcements 5 arranged alternately with prestressed steel rods 3; two short reinforcements are 6.5m in length, as the first-level short reinforcement, and the remaining two short reinforcements are 4m in length, as The second-level short reinforcement, the two-level short reinforcement is arranged symmetrically with the steel cage axis as the central axis, the top of the first-level short reinforcement is 2.5m away from the pole tip, and the second-level short reinforcement is 5m away from the pole tip. The inner flange is installed at the pole tip of the lower 9m pole section.

The production technology of present embodiment pole is as follows:

1.1. Arrange a group of non-prestressed tendons (composed of eight non-prestressed main tendons 4 and two short tendons 5) distributed around its axis according to the size and taper (1:75) of the proposed pole section, each non-prestressed tendon The taper of the stress tendons relative to the axis of the proposed pole section is 1:75; and then weld a circle of inner steel hoops 6 at intervals of 500mm along the axial direction of the cage on the inside of the cage surrounded by each non-prestressed tendon (using steel bars with a diameter of 6 mm), and each inner steel hoop 6 is coaxially arranged, and the inner steel hoops are welded in the form of a double inner steel hoop within a range of one meter from both ends; A prestressed anchor steel plate 1 is coaxially installed, and when the prestressed anchor steel plate 1 is arranged, the holes 15 are adjusted so that the connection line corresponding to the two holes 15 is alternate with each non-prestressed main rib 4 .

1.2. On the two prestressed anchor steel plates 1, insert a prestressed steel rod 3 for concrete into each corresponding two holes 15 (eight prestressed steel rods are set up in this embodiment, and they are connected with the non-prestressed main reinforcement 4 arranged alternately), and the anchoring end of the prestressed steel rod is anchored on the outer surface of one of the prestressed anchoring steel plates 1, and the tension end is threaded to connect a nut 2 that is tightly pressed against the outer surface of the other prestressed anchoring steel plate 1, Realize the locking and forming of the prestressed anchor steel plate 1, the prestressed steel rod 3 and the cage body, and at the same time ensure that the taper of each prestressed steel rod 3 relative to the axis of the proposed pole section is the same (1:75); as shown in Figure 3 , for a prestressed steel bar 3 with a pier head 20 at one end and a threaded structure at the other end, the end with the pier head 20 is used as the anchoring end to limit the outer side of one of the prestressed anchoring steel plates 1, and then the other end is cut off (Zhang pull end) the outer jacket 21 at the end, and use the nut 2 to tighten the limit and the outer surface of another prestressed anchor steel plate 1; 2 Lock and fix.

1.3. Spiral steel bars 7 with a diameter of 4 mm are continuously and densely wound round by round on the outer side of the cage body in a spiral winding manner, and densely wound within a range of one meter from both ends to form a steel bar cage.

1.4. Hoist the reinforcement cage obtained in step 1.3 into the pole steel mold base, clamp the shoulder clips 23 of the two prestressed anchor steel plates 1 into the grooves, and tighten the nuts 2 to ensure that each prestressed steel rod 3 is relatively The taper of the electric pole section is the same, pour concrete slurry, clear the edge of the steel mold, close the upper cover of the steel mold, close the mold, tighten the mold clamping bolts of the steel mold, tighten the nut 2 again, and put the steel mold The whole is hoisted into the centrifuge, and the centrifuge gradually increases the speed, from low speed to medium speed and finally to 1050 rpm. After being centrifuged, it is hoisted away, placed in balance, and demoulded after 3 days of natural curing, and then naturally cured for 21 days.

1.5. Implement tensioning at the tensioning end, lock the 3 tensioning ends of the prestressed steel rod through the tool anchor, and then use the hydraulic press to expand the tensioning. The tensioning value is 835.2KN. After reaching the tensioning design value, lock the nut 2. Tensioned and elongated prestressed steel rod 3 threads remain half of the nut, and the excess part is sawn off.

1.6. Install the inner flange at the butt end (that is, the root end), specifically, first weld the cylindrical inner ring plate 17 coaxially on the outer surface of the prestressed anchor steel plate 1 at the butt end, and then weld the inner steel ring plate 17 coaxially on the inner steel ring plate 1. A group of reinforcing rib plates 16 is evenly welded radially around the ring plate, and then a butt plate 18 parallel and coaxial to the prestressed anchoring steel plate 1 is welded on the inner ring plate 17 and the reinforcing rib plate 16, and the reinforcing rib plate On the outer side of 16, two steel bars 19 with a diameter of 5 mm are wound every 30 mm from the prestressed anchoring steel plate 1, and welded to the stiffened plate 16. Finally, the slag is cleaned and filled with epoxy mortar 13 to form a gap between the exposed nut 2 and the pier head 20. Closed protection, that is, to complete the preparation of the upper 6m pole section.

Then prepare the lower 9m pole section according to the above steps, the difference is that the reinforcement is different, and the reinforcement cage is arranged with twelve prestressed steel rods 3 and twelve non-prestressed main reinforcements with a length of 9m and arranged alternately with the prestressed steel rods 3 4. Four short bars 5; two of the short bars are 6.5m in length, as the first-level short bars, and the other two short bars are 4m in length, as the second-level short bars. The central axis is symmetrically arranged, the top of the first-level short rib is 2.5m away from the pole tip, and the second-level short rib is 5m away from the pole tip. The inner flange is installed at the pole tip of the lower 9m pole section. The tensile value is 1252.8KN.

As shown in Figure 10, finally, the bolts of the upper section and the lower section can be butted into a whole through the inner flange, which avoids on-site welding.

The inspection bending moment of the electric pole prepared by the method of this embodiment can reach 173.83KN.m, which is 177.37% higher than the strongest inspection bending moment of the electric pole of the same specification in the national standard, and exceeds that in Table 4 of the GB/4623-2006 standard The listed ∮350mm×15m pole’s S-class is 159.68KN.m, which is 17.69KN.m higher than the bending moment. Rods, straight steel pipe rods, and straight iron towers reduce the weight. The rods are suitable for the erection of four circuits of large-section conductor distribution lines on the same rod, and the tip diameter is moderate, which is beneficial to construction operations. The segmented type is convenient for transportation, and the bolt butt joint avoids on-site welding.

Claims (10)

1. A high-strength post-tensioned reinforced concrete pole, which includes a hollow truncated concrete body (8) as a whole, a reinforcement cage embedded in the side wall of the concrete body, and a The two disc-shaped prestressed anchor steel plates (1) arranged on the axis are characterized in that: on the prestressed anchor steel plate (1), a ring-shaped hole (15) is uniformly distributed around the center of the prestressed anchor steel plate (1), and The holes (15) on the two prestressed anchor steel plates (1) are arranged in one-to-one correspondence; the reinforcement cage includes a set of prestressed steel rods (3) for concrete uniformly distributed around the axis of the concrete body (8), a set of The non-prestressed main reinforcement (4) arranged alternately with the prestressed steel rod (3) and evenly distributed around the axis of the concrete body (8), an even number of short reinforcements (5) distributed symmetrically with the axis of the concrete body (8) as the central axis, A set of inner steel hoops (6) welded at the inner side of the cage surrounded by non-prestressed main reinforcement (4) and short reinforcement (5) and evenly spaced along its axial direction, and a helical hoop wound spirally on the outside of the cage Reinforcement bars (7), wherein the two ends of the prestressed steel rods (3) pass through the corresponding two holes (15) on the two prestressed anchor steel plates (1), and the anchor ends pass through the integrally formed piers (20 ) or the threaded nut (2) is limited to the outer surface of one of the prestressed anchoring steel plates (1), and the tension end is stretched and then the threaded nut (2) is limited to the other prestressed anchoring steel plate (1) ), the taper of each prestressed steel rod (3) relative to the axis of the concrete body (8) is the same after tension. 2. The high-strength post-tensioned reinforced concrete pole according to claim 1, characterized in that: the prestressed anchor steel plate (1) is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12-20mm , its outer side is processed with a shoulder clip (23) protruding from the pole body, and its thickness is half of the thickness of the prestressed anchoring steel plate (1). 3. The high-strength post-tensioned reinforced concrete pole according to claim 1 or 2, characterized in that: the prestressed steel rod (3) adopts a tensile strength value of 1570N/mm ² and a relaxation rate of 1000h ≤ 2.5 %, 9-12mm in diameter prestressed steel rods for unbonded smooth concrete, coaxially covered with a plastic jacket (21), and filled with anti-corrosion lubricating grease. 4. The high-strength post-tensioned reinforced concrete pole according to claim 1 or 2, characterized in that: the non-prestressed main bars (4) and short bars (5) are all made of HRB500 ordinary steel bars, and their tensile strength 435N/mm ² , compressive strength 410 N/mm ² , diameter 12mm or 14 mm; short bars (5) are arranged symmetrically in stages, the number of short bars (5) in each level is an even number, the length is the same, and The arrangement is symmetrical with the reinforcement cage axis as the central axis, and the length difference between two adjacent short bars (5) is 2.5m. 5. The high-strength post-tensioned reinforced concrete pole according to claim 1 or 2, characterized in that: the inner steel hoop (6) is formed by bending a steel bar with a diameter of 6 mm, and two adjacent inner steel hoops (6 ) is 500mm in the axial direction; the diameter of the spiral reinforcement (7) is 4mm; the taper of each prestressed steel rod (3) relative to the axis of the concrete body (8) and the taper of the pole are both 1:75±5. 6. A high-strength post-tensioned reinforced concrete pole, which includes at least two pole sections; each pole section includes a hollow frustum-shaped concrete body (8) as a whole, and a concrete body embedded in the side wall of the concrete body. A reinforcement cage, and two disc-shaped prestressed anchor steel plates (1) located at both ends of the concrete body and coaxially arranged, characterized in that: the prestressed anchor steel plates (1) are uniformly distributed A ring of holes (15) arranged in a circle, and the holes (15) on the two prestressed anchor steel plates (1) are arranged in one-to-one correspondence; the reinforcement cage includes a set of uniformly distributed around the axis of the concrete body (8) Prestressed steel rods (3) for concrete, a group of non-prestressed main bars (4) arranged alternately with the prestressed steel rods (3) and evenly distributed around the axis of the concrete body (8), an even number A group of inner steel hoops (6) that are symmetrically distributed on the central axis (5) and inside the cage surrounded by the non-prestressed main reinforcement (4) and the short reinforcement (5) and welded at intervals along its axial direction , and the spiral reinforcement (7) spirally wound on the outside of the cage, wherein the two ends of the prestressed steel rod (3) respectively pass through the two corresponding holes (15) on the two prestressed anchor steel plates (1), And its anchoring end is limited on the outer surface of one of the prestressed anchoring steel plates (1) through an integrally formed pier head (20) or a threaded nut (2), and the tensioning end is stretched through a threaded nut ( 2) It is limited to the outer surface of another prestressed anchor steel plate (1), and the taper of each prestressed steel rod (3) relative to the axis of the concrete body (8) after tension is the same; the butt ends of each pole section are installed There is an inner flange, and each pole section is connected by inner flange bolts to form a whole. 7. The high-strength post-tensioned reinforced concrete pole according to claim 6, characterized in that: the inner flange includes a cylindrical inscribed joint coaxially welded on the outer surface of the prestressed anchor steel plate (1) at the butt joint Steel rim plate (17), a group of stiffener plates (16) uniformly welded on the periphery of the inner rim plate in the radial direction, welded on the top of the inner rim plate (17) and the stiffener plate (16), and The prestressed anchor steel plate (1) is parallel and coaxially arranged butt steel plates (18), and two steel bars (19) are wound on the outside of the stiffener plate (16) and welded thereto. 8. The high-strength post-tensioned reinforced concrete pole according to claim 6 or 7, characterized in that: the prestressed anchor steel plate (1) is made of No. 45 steel after quenching and tempering heat treatment, and its thickness is 12 -20mm, its outer side is processed with a shoulder clip (23) protruding from the pole body, and its thickness is half of the thickness of the prestressed anchoring steel plate (1). 9. The high-strength post-tensioned reinforced concrete pole according to claim 6 or 7, characterized in that: the prestressed steel rod (3) adopts a tensile strength value of 1570N/mm ² and a relaxation rate of 1000h ≤ 2.5 %, 9-12mm in diameter prestressed steel rods for unbonded smooth concrete, coaxially covered with a plastic jacket (21), and filled with anti-corrosion lubricating grease. 10. The high-strength post-tensioned reinforced concrete pole according to claim 6 or 7, characterized in that: the non-prestressed main bars (4) and short bars (5) are all made of HRB500 ordinary steel bars, and their tensile strength 435N/mm ² , compressive strength 410 N/mm ² , diameter 12mm or 14 mm; short bars (5) are arranged symmetrically in stages, the number of short bars (5) in each level is an even number, the length is the same, and The axis of the steel cage is symmetrically arranged, and the length difference between two adjacent short bars (5) is 2.5m; the inner steel hoop (6) is made of bent steel bars with a diameter of 6mm, and the adjacent two inner steel hoops ( 6) The axial distance between them is 500mm; the diameter of the spiral steel bar (7) is 4mm; the taper of each prestressed steel bar (3) relative to the axis of the concrete body (8) and the taper of the electric pole are both 1:75±5 .