CN114214916A - Prestressed top-pressing anchor-pulling system and construction method - Google Patents

Abstract

The invention discloses a prestressed jacking and pulling anchor system and a construction method thereof, and the prestressed jacking and pulling anchor system comprises an anchoring part, a tensioning part and a jacking mechanism, wherein a compression bar is arranged between the anchoring part and the tensioning part, the lower end of the compression bar is connected with the anchoring part, a plurality of prestressed ribs are connected between the anchoring part and the tensioning part, a jacking part is connected above the tensioning part, the jacking mechanism comprises a pressing end and a buckling and grabbing end, the pressing end penetrates through the jacking part and the tensioning part and then abuts against the upper end of the compression bar, the buckling and grabbing end is buckled at the lower end of the tensioning part, and the buckling and grabbing end drives the tensioning part to move upwards to be tightly attached to the jacking part after being pressed by the jacking mechanism so as to apply prestress to the prestressed ribs. The invention can apply reliable prestress to the concrete structure, does not need to reserve pore channels and grout during tensioning, fundamentally stops the possibility of prestress failure, greatly improves the reliability and durability of the concrete structure, and has the advantages of simple structure, clear stress, flexible construction and simple and convenient installation.

Description

Prestressed top-pressing anchor-pulling system and construction method

Technical Field

The invention relates to the technical field of prestressed concrete bridge or prestressed concrete structural engineering, in particular to a prestressed top pressure pulling anchor system and a construction method.

Background

From the prestress tension sequence of the prestressed concrete structure, the prestressed concrete structure is divided into a pre-tensioning method prestressed system and a post-tensioning method prestressed system.

The pretensioning prestressed system is that steel bundles or steel bars anchored on a pedestal are tensioned firstly, then concrete is poured, the steel bundles or the steel bars are cut off after the concrete reaches a certain strength, and prestress is applied to a concrete member by means of the self-retraction of the steel bundles or the steel bars. The advantages of the pre-tensioning process are that no pipe hole is needed, the prestressed bar is directly bonded with the concrete, the loss of prestress is small, and the durability effect of the member is far superior to that of post-tensioning prestress. The process has the defects that strong loading beam equipment and beam manufacturing pedestals are needed, the prestressed tendons are not easily configured on the broken lines, and the process is only suitable for an industrial prefabrication production mode generally.

The post-tensioning prestressed concrete system is characterized in that a hole channel is reserved firstly, concrete is poured, after the concrete meets the strength requirement, a prestressed tendon is inserted into the reserved hole channel, and a formed concrete member is used as a force application system to tension the prestressed tendon, so that the purpose of enabling the concrete to obtain prestress is achieved. The post-tensioning process has the advantages of flexible construction and can be adopted for both factory prefabrication and field construction. The method has the disadvantages that the processes of reserving a pore channel, grouting, sealing an anchor and the like are needed, certain interference is caused to construction, grouting failure or bleeding is easy to occur during grouting in the pore channel, the bonding between a grouting material and the prestressed tendon is reduced, and the prestressed tendon is easy to corrode.

Based on the above situation, how to design a prestressed jacking and pulling anchor system and a construction method which can apply reliable prestress to a structure, do not need to reserve a pore channel and grout during tensioning, fundamentally avoid the possibility of prestress failure, greatly improve the reliability and durability of the structure, have simple structure, clear stress, flexible construction and simple and convenient installation, and become the subject of diligent research of the inventor.

Disclosure of Invention

The invention aims to provide a prestress top pressure anchor system and a construction method, which can apply reliable prestress to a structure, do not need to reserve a pore channel and grout during tensioning, fundamentally avoid the possibility of prestress failure, greatly improve the reliability and durability of the structure, and have the advantages of simple structure, clear stress, flexible construction and simple and convenient installation.

In order to achieve the purpose, the invention provides a prestressed jacking and pulling anchor system which comprises an anchoring part, a tensioning part, a jacking part and a jacking mechanism, wherein a compression rod is arranged between the anchoring part and the tensioning part, the lower end of the compression rod is connected with the anchoring part, a plurality of prestressed ribs are connected between the anchoring part and the tensioning part, the upper surface of the tensioning part is connected with the jacking part, the jacking mechanism comprises a pressing end and a buckling and grabbing end, the pressing end penetrates through the jacking part and the tensioning part and then abuts against the upper end of the compression rod, the buckling and grabbing end is buckled at the lower end of the tensioning part, and after the jacking mechanism applies pressure, the buckling and grabbing end drives the tensioning part to move upwards and abut against the jacking part, so that prestress is applied to the prestressed ribs.

Preferably, a grout blocking sleeve is arranged between the anchoring part and the tensioning part, and the compression bar is positioned in the grout blocking sleeve.

Preferably, the upper surface of the anchoring part is provided with an annular first bulge, the lower surface of the tensioning part is provided with an annular second bulge, the lower end of the pressing rod is installed in the inner cavity of the first bulge, the lower end of the jacking mechanism penetrates through the jacking part and the second bulge and then abuts against the upper end of the pressing rod, and the upper end and the lower end of the grout blocking sleeve are installed on the outer surfaces of the second bulge and the first bulge.

Preferably, the upper end of the pressure lever is 3-5cm away from the second protrusion.

Preferably, the outer surface of the grout blocking sleeve is provided with a plurality of stabilizing rings, the stabilizing rings are arranged from bottom to top at intervals, and each prestressed tendon passes through each stabilizing ring.

Preferably, the stabilizing ring is composed of a ring plate and a pipe body penetrating through the upper end and the lower end of the ring plate, the stabilizing ring is provided with a first through hole for the compression bar to penetrate through, the cross section size of the first through hole is matched with that of the compression bar, and the stabilizing ring is provided with a plurality of second through holes for the prestressed ribs to penetrate through.

Preferably, the prestressed tendons are circumferentially arranged in a circle by taking the compression bar as a circle center.

Preferably, the prestressed tendons adopt steel wires with the yield strength of more than or equal to 1670MPa, and the prestressed tendons are anchored with the anchoring part and the tensioning part through heading anchors.

Preferably, the lower surface of the pressing part is provided with a groove, the upset head anchor is positioned in the groove after the prestress is tensioned to the position, and the upset head anchor is not in contact with the groove bottom of the groove.

Preferably, the compression bar is a metal bar with a circular or polygonal cross section.

Preferably, the jacking mechanism includes a jacking screw, a jack and two buckling parts, the lower end of the jacking screw passes through the jacking part and the tensioning part and then abuts against the upper end of the compression bar, the jacking screw is connected with the jacking part through a bolt, the piston of the jack abuts against the upper end of the jacking screw, the buckling parts are arranged on two sides of the cylinder body of the jack, the buckling parts are buckled at the lower end of the tensioning part, when the oil cylinder of the jack is pressurized, the oil cylinder is opposite to the piston to move upwards, so that the buckling parts drive the tensioning part to move upwards and the jacking part to be tightly attached, and therefore prestress is applied to the prestressed ribs.

Preferably, the buckling and grabbing part is an L-shaped buckling claw hinged to the jack cylinder.

Preferably, the upper surface of the jacking portion is provided with a boss, and the screw rod penetrates through the boss.

A construction method of a prestressed jacking and pulling anchor system comprises the following steps:

(1) the pressing end of the pressing mechanism of the anchor pulling system is abutted against the upper end of the pressing rod, the buckling and grabbing end of the pressing mechanism is buckled with the lower end of the tensioning part, so that the pressing mechanism presses the pressing rod until the pressing part is tightly attached to the tensioning part, and prestress is applied to the prestressed ribs;

(2) then, locking the jacking portion and the tensioning portion by using a fastener, stopping pressurizing the jacking mechanism, loosening the clamping jaw end and the tensioning portion, and finishing the prestress tensioning operation;

(3) and (3) binding, installing and positioning the prestressed jacking and pulling anchor system obtained in the step (2) with the concrete structure, after the concrete is poured and cured to reach the strength, loosening the fastening pieces on the jacking portion and the tensioning portion, and automatically transferring force and anchoring the prestressed tendons to enable the prestress to act on the concrete structure.

After the scheme is adopted, the prestress top pressure anchor pulling system and the construction method have the following beneficial effects:

(1) the prestressed reinforcement tensioning device is simple in structural design and clear in force transmission, and the prestressed reinforcements are tensioned by jacking the tensioning part and the jacking part through the jacking mechanism, so that the prestressed stress pre-applied to the concrete structure is stored in the prestressed reinforcements, and the tension of the prestressed reinforcements and the pressure of the pressure rod form a tension-compression self-balancing system.

(2) The invention has stable holding performance, the tensioned prestressed tendon and the compressed compression bar are both in an elastic working state, the tension force of the prestressed tendon can be well kept unchanged, and effective and reliable prestress can be applied to a concrete structure.

(3) The prestressed reinforcement is simple to apply prestress to the concrete structure, a hole channel is not required to be reserved, grouting is not required, the prestressed reinforcement is only installed and positioned together when reinforcing steel bars are bound, after the concrete is poured and cured to reach the strength, the connection between the tensioning part and the jacking part is removed, the components such as the tensioning part, the jacking part, the compression bar and the like can be detached, and the prestressed reinforcement automatically realizes force transmission and anchoring so that the prestress acts on the concrete structure.

(4) The invention has flexible construction, and is suitable for factory prefabrication and field construction.

(5) The components such as the pressure lever, the jacking portion, the jacking screw rod and the like can be repeatedly used, and the consumption of steel can be saved.

(6) The invention has simple manufacture and convenient installation, has the advantages of pre-tensioning method applied prestress and being suitable for cast-in-place concrete construction, can effectively avoid common diseases such as anchorage deflection, non-compact pipeline grouting, delayed steel bar fracture and the like during post-tensioning method prestressed tensioning, can replace IV-level high-strength steel bars in the conventional concrete box girder web plate design, and fundamentally eliminates the possibility of vertical prestress failure.

Drawings

FIG. 1 is a schematic structural view of a prestressed push-pull anchor system according to the present invention;

FIG. 2 is a schematic view of an anchoring part of the prestressed push-pull anchoring system according to the present invention;

FIG. 3 is a schematic sectional view taken along line A-A of FIG. 2;

FIG. 4 is a schematic diagram of a structure of a tension part of the prestressed roof pressure anchor system according to the present invention;

FIG. 5 is a schematic sectional view taken along line B-B of FIG. 4;

FIG. 6 is a schematic view of the structure of the pressing portion of the prestressed pressing and pulling anchor system according to the present invention;

FIG. 7 is a schematic cross-sectional view taken along line C-C of FIG. 6;

FIG. 8 is a schematic view of a stabilizing ring structure of the prestressed push-pull anchor system according to the present invention;

FIG. 9 is a schematic cross-sectional view taken along line D-D of FIG. 8;

FIG. 10 is a schematic view of a top pressure screw of the prestressed top pressure anchor system according to the present invention;

fig. 11 is a schematic structural view of an embodiment of the prestressed push-pull anchor system according to the present invention.

Detailed Description

The invention will be elucidated on the basis of an embodiment shown in the drawing. The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is not limited to the following description of the embodiments, but is defined only by the scope of the claims, and includes all modifications having the same meaning as and within the scope of the claims.

The prestressed top pressure anchor system related to the invention is specifically explained in the following by combining the drawings in the specification.

As shown in fig. 1, the structural schematic diagram of the prestressed top pressure pulling anchor system of the present invention includes an anchoring portion 1, a tensioning portion 2, a top pressure mechanism 3, a pressing rod 4, a plurality of prestressed tendons 5, and a top pressure portion 6. The compression bar 4 is arranged between the centers of the anchoring part 1 and the tensioning part 2, the upper end of the compression bar is spaced from the tensioning part 2 by a certain distance, the lower end of the compression bar 4 is connected with the anchoring part 1, and a plurality of prestressed ribs 5 are connected between the anchoring part 1 and the tensioning part 2.

Referring to fig. 2 and 3, the anchor part 1 of the present embodiment is made of a rectangular plate, and is preferably made of a Q345 steel plate. The thickness of the plate needs to meet the rigidity and strength requirements required by the jacking of the pressure rod 4. The upper surface of the anchoring portion 1 is provided with a ring-shaped first projection 7. A plurality of first pre-stressed rib holes 8 are circumferentially arranged on the anchoring part 1 by taking the first protrusion 7 as a circle center, and eight first pre-stressed rib holes 8 are arranged in the embodiment.

Referring to fig. 4 and 5, the tension part 2 of the present embodiment is made of a rectangular plate made of structural steel, preferably a Q345 steel plate. The plate thickness of the steel plate needs to meet the requirements of rigidity and strength required by tension prestress. A circular hole is arranged at the center of the stretching part, an annular second bulge 9 with the lower end extending out of the lower surface of the stretching part 2 is welded on the circular hole, and a through hole 21 is arranged in the inner cavity of the second bulge 9. The tensioning portion 2 is provided with a plurality of second prestressed reinforcement holes 10 in the circumferential direction around the second protrusion 9, and this embodiment is provided with eight second prestressed reinforcement holes 10, and the positions of the second prestressed reinforcement holes correspond to the positions of the first prestressed reinforcement holes 8 up and down. A plurality of four locking bolt holes 11 are provided in the tension portion 2 at positions close to the outer edge.

The compression bar 4 is made of a metal rod with a circular or polygonal cross section, and in the embodiment, a steel rod with a circular cross section, preferably made of carbon structural steel, is arranged along the axial direction and is provided with an equal cross section.

The lower end of the pressure lever 4 is arranged in the inner cavity of the first bulge 7 of the anchoring part 1, and the distance from the upper end of the pressure lever 4 to the second bulge 9 is 3-5 cm.

The upper surface of the tension part 2 is in threaded connection with the top pressure part 6 through a plurality of fastening bolts 12, the fastening bolts 12 of the embodiment adopt M24 high-strength bolts of 10.9 grade, and the fastening bolts 12 are arranged to maintain the prestress of the prestressed tendon 5. The fastening bolt 12 can be recycled after the prestressing has been applied to the structure.

Referring to fig. 6 and 7, the pushing portion 6 of the present embodiment is made of a rectangular plate, and the pushing portion 6 of the present embodiment is made of 40Cr or 45 steel. A cylindrical boss 13 is provided on the upper surface of the pressing portion 6, and a screw hole 14 is provided at the axial center position of the boss 13 and the pressing portion 6. The lower surface of the top pressing portion 6 is provided with a cylindrical groove 15, and the depth of the groove 15 is 10mm in the embodiment. The groove 15 is connected with the screw hole 14 to form a T-shaped hole, and the part of the jacking portion 6 close to the outer edge is provided with a plurality of screw holes 25 for the fastening bolts 12 to pass through in a threaded manner along the circumferential direction.

A grout blocking sleeve 16 is arranged between the anchoring part 1 and the tensioning part 2, and the grout blocking sleeve 16 is a polyvinyl chloride hard pipe in the embodiment. The upper end and the lower end of the slurry blocking sleeve 16 are respectively arranged on the outer surface of the second bulge 9 and the outer surface of the first bulge 7. The press rod 4 is positioned in the inner cavity of the slurry blocking sleeve 16, and the slurry blocking sleeve 16 is arranged for isolating the press rod 4 from contacting with concrete.

According to the stability requirement of the compression bar 4, a plurality of stabilizing rings 17 are arranged on the outer surface of the grout blocking sleeve 16 at intervals along the axial direction of the grout blocking sleeve, the stabilizing rings 17 are arranged from bottom to top at intervals, and the stabilizing rings 17 are arranged to improve the stable bearing capacity of the compression bar 4. Referring to fig. 8 and 9, the stabilizing ring 17 is composed of a ring plate and a pipe body passing through the upper and lower ends of the ring plate, the pipe body structure of this embodiment is a 1.5 inch water gas pipe, the ring plate is a 2mm thick Q235 circular steel plate, and the water gas pipe and the circular steel plate are welded to form the stabilizing ring 17. The center of the stabilizing ring 17 is provided with a first through hole 18 for the compression bar 4 to pass through, and the first through hole 18 is an inner cavity of the water gas pipe in the embodiment. The cross-sectional dimension of the first through hole 18 is matched with that of the compression bar 4, and a plurality of second through holes 19 for the prestressed tendons 5 to pass through are arranged on the stabilizing ring 17.

The prestressed tendons 5 are circumferentially arranged in a circle by taking the compression bar 4 as a circle center. In this embodiment, the tendon 5 is made of a high-strength indented steel wire having a yield strength of 1670MPa or more and a diameter of Φ 7.

The upper end of the prestressed tendon 5 and the anchoring part 1, and the lower end of the prestressed tendon 5 and the tensioning part 2 are anchored together through a heading anchor 20. The upset head anchor 20 is arranged in the groove 15 on the lower surface of the top pressing part 6, and when the prestress is tensioned to the position, the upset head anchor 20 is not contacted with the groove bottom of the groove 15.

The pressing end of the pressing mechanism 3 downwards penetrates through the boss 13, the screw hole 14 on the pressing part 6 and the through hole 21 of the second protrusion 9 of the tensioning part 2 and then is pressed against the upper end of the pressing rod 4, and the tensioning part 2 and the pressing part 6 can be tightly attached through the pressing mechanism 3, so that the plurality of prestressed ribs 5 are subjected to preset prestress.

The jacking mechanism 3 comprises a jacking screw 22, a jack 23 and two buckling parts 24. Referring to fig. 10, the pressing screw 22 is a T-shaped screw, the outer surface of the head end of the T-shaped screw is knurled, and the rod part is provided with T34 trapezoidal threads, so as to ensure the pressing force requirement and the accuracy of the tensioning stroke. After the prestressing force is applied to the structure, the top pressure screw 22 can be recycled. The lower end (i.e. the pressing end) of the pressing screw 22 downwards passes through the screw hole 14 and the through hole 21 and then presses against the upper end of the pressing rod 4, and the screw 22 is screwed with the pressing part 6. The piston of the jack 23 is pressed against the upper end of the top pressure screw 22, the two buckling and grabbing parts 24 are arranged on two sides of the cylinder body of the jack 23 in a bilateral symmetry mode, the two buckling and grabbing parts 24 are buckled at the lower end of the tensioning part 2, and the buckling and grabbing parts 24 are L-shaped buckling claws hinged to the cylinder body of the jack 23. When the oil cylinder of the jack 23 is pressurized, the oil cylinder moves upwards relative to the piston, so that the two buckling parts 24 drive the tensioning part 2 to move upwards to be attached to the top pressing part 6, and prestress is applied to the prestressed ribs 5.

When the prestressed top pressure anchor system is constructed, the prestressed tensioning operation is firstly carried out, and the operation is generally carried out on site. The two buckling parts 24 arranged on the cylinder body of the jack 23 are buckled at the lower end of the tensioning part 2, an oil cylinder of the jack 23 is pressurized, a piston of the jack 23 applies force to the upper surface of the jacking screw rod 22 and the lower surface of the tensioning part 2, the oil cylinder moves upwards relative to the piston, the tensioning part 2 is enabled to move upwards under the action of the upward force until the tensioning part 2 is tightly attached to the jacking part 6, and the tensioning part 2 drives the prestressed tendon 5 to stretch upwards, so that prestress is applied to the prestressed tendon 5. And the compressed compression bar 4 is in an elastic working state, so that the tension force of the prestressed tendon 5 can be well kept unchanged, and effective and reliable prestress can be applied to the structure. And then the jacking part 6 and the tensioning part 2 are screwed down by a plurality of fastening bolts 12, so that the oil return of the jack 23 can be unloaded, the buckling part 24 is loosened, and the prestress tensioning operation is finished.

Then, prestress is applied to the concrete structure, and as shown in fig. 11, the prestress top pressure anchor system 26 and the concrete structure 27 which are completed by the tensioning operation are installed and positioned by binding steel bars. After the concrete is poured and cured to reach the strength, the fastening bolts 12 on the top pressure part 6 and the tensioning part 2 are loosened, at the moment, the prestressed tendons 5 can apply the prestress to the concrete structure 27, the tensioning part 2 is finished, in order to not influence the subsequent construction, the heading anchor 20 can be cut off, the tensioning part 2 is removed, meanwhile, the top pressure part 6, the compression bar 4 and other components are also removed, the prestressed tendons 5 automatically realize force transferring and anchoring, and the prestress acts on the concrete structure 27.

The prestressed jacking and pulling anchor system has simple structural design and definite force transfer, and realizes the tensioning of the prestressed tendons 5 by jacking the tensioning part 2 and the jacking part 6 through the jacking mechanism 3, so that the prestressed force pre-applied to the concrete structure 27 is firstly stored in the prestressed tendons 5, and the tension of the prestressed tendons 5 and the pressure of the pressure rod 4 form a tension and compression self-balancing system. The invention has stable holding performance, the tensioned prestressed tendon 5 and the compressed compression bar 4 are both in an elastic working state, the tension force of the prestressed tendon 5 can be well kept unchanged, and effective and reliable prestress can be applied to the concrete structure 27. The operation of applying prestress to the concrete structure is simple, a pore channel does not need to be reserved, grouting is not needed, the prestressed reinforcement concrete is only installed and positioned together when reinforcing steel bars are bound, after the concrete is poured and cured to reach the strength, the fastening bolt 12 between the tensioning part 2 and the jacking part 6 is released, and the prestressed reinforcement 5 automatically realizes force transmission anchoring so that the prestress acts on the concrete structure 27. The invention has flexible construction, and is suitable for factory prefabrication and field construction. The components of the pressure lever 4, the jacking part 6, the jacking screw 22, the fastening bolt 12 and the like can be repeatedly used, so that the consumption of steel can be saved.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims (14)

1. The utility model provides an anchor system is drawn in prestressing force roof pressure, its characterized in that, includes anchor portion, stretch-draw portion, top splenium and roof pressure mechanism, be equipped with the depression bar between anchor portion and the stretch-draw portion, the lower extreme of depression bar with anchor portion connects, be connected with a plurality of prestressing tendons between anchor portion and the stretch-draw portion, the higher authority of stretch-draw portion is connected top splenium, roof pressure mechanism is including supporting the pressure end and detaining the hold end, support the pressure end and pass support the upper end at the depression bar behind top splenium and the stretch-draw portion, it detains to detain the hold end the lower extreme of stretch-draw portion, detain the hold end and exert pressure the back at roof pressure mechanism, drive stretch-draw portion rebound and top splenium are pasted tightly, give a plurality of prestressing force is applyed to the prestressing tendons.

2. The prestressed roof-pressure anchor system as claimed in claim 1, wherein a grout-blocking sleeve is provided between the anchoring portion and the tensioning portion, and the pressing rod is located in the grout-blocking sleeve.

3. The prestressed roof pressure and pull anchor system as claimed in claim 2, wherein the upper surface of the anchoring portion is provided with a ring-shaped first protrusion, the lower surface of the tension portion is provided with a ring-shaped second protrusion, the lower end of the pressing rod is installed in the inner cavity of the first protrusion, the lower end of the roof pressure mechanism passes through the roof pressure portion and the second protrusion and then abuts against the upper end of the pressing rod, and the upper end and the lower end of the grout blocking sleeve are installed on the outer surfaces of the second protrusion and the first protrusion.

4. The prestressed roof pressure and pull anchor system as claimed in claim 3, wherein the upper end of the pressure bar is 3-5cm from the second projection.

5. The prestressed roof pressure pulling anchor system as claimed in claim 2, wherein a plurality of stabilizing rings are arranged on the outer surface of the grout blocking sleeve at intervals from bottom to top, and each tendon passes through each stabilizing ring.

6. The prestressed roof pressure anchor system as claimed in claim 5, wherein said stabilizer ring is composed of a ring plate and a tube body passing through the upper and lower ends of said ring plate, said stabilizer ring is provided with a first through hole for said compression bar to pass through, the cross-sectional dimension of said first through hole matches with the cross-sectional dimension of said compression bar, said stabilizer ring is provided with a plurality of second through holes for said prestressed ribs to pass through.

7. The prestressed roof pressure and pull anchor system as claimed in claim 6, wherein a circle of prestressed ribs is circumferentially arranged around the compression bar.

8. The prestressed roof pressure and pull anchor system as claimed in claim 1, wherein said prestressed tendons are steel wires with yield strength greater than or equal to 1670MPa, and said prestressed tendons are anchored with said anchoring portion and said tension portion by means of heading anchors.

9. The prestressed roof pressure anchor system as claimed in claim 8, wherein the lower surface of said roof portion is provided with a groove, said upset anchor is located in said groove after the prestressed tension anchor is in place, and said upset anchor is not in contact with the bottom of said groove.

10. The prestressed roof pressure anchor system as claimed in claim 1, wherein the pressure bar is a metal rod with a circular or polygonal cross section.

11. The prestressed jacking and pulling anchor system according to claim 1, wherein the jacking mechanism comprises a jacking screw, a jack and two buckling parts, the lower end of the jacking screw passes through the jacking part and the tensioning part and then abuts against the upper end of the compression bar, the jacking screw is in bolted connection with the jacking part, a piston of the jack abuts against the upper end of the jacking screw, the two buckling parts are mounted on two sides of a cylinder body of the jack, the two buckling parts are buckled at the lower end of the tensioning part, and after an oil cylinder of the jack is pressurized, the oil cylinder moves upwards relative to the piston to enable the two buckling parts to drive the tensioning part to move upwards to be tightly attached to the jacking part, so that prestress is applied to the plurality of prestressed ribs.

12. The prestressed push-pull anchor system according to claim 11, wherein said grasping portion is an L-shaped grasping claw hinged to said jack cylinder.

13. The prestressed push-pull anchor system according to claim 11, wherein a boss is provided on the upper surface of said push-press portion, and said screw rod passes through said boss.

14. A construction method of a prestressed jacking and pulling anchor system is characterized by comprising the following steps:

(1) pressing the pressing rod by using a pressing end of a pressing mechanism of the anchor pulling system according to any one of claims 1 to 13 to abut against an upper end of the pressing rod, and fastening a lower end of the tensioning part by using a fastening and grasping end of the pressing mechanism, so that the pressing mechanism presses the pressing rod until the pressing part abuts against the tensioning part, thereby realizing prestressing of the plurality of prestressed ribs;

(2) then, locking the jacking portion and the tensioning portion by using a fastener, stopping pressurizing the jacking mechanism, loosening the clamping jaw end and the tensioning portion, and finishing the prestress tensioning operation;

(3) and (3) binding, installing and positioning the prestressed jacking and pulling anchor system obtained in the step (2) with the concrete structure, after the concrete is poured and cured to reach the strength, loosening the fastening pieces on the jacking portion and the tensioning portion, and automatically transferring force and anchoring the prestressed tendons to enable the prestress to act on the concrete structure.

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