CN118881177A - Prestressed tension anchor system and construction method - Google Patents

Abstract

The invention discloses a prestress stretch-draw sealing anchor system and a construction method, and belongs to the technical field of anchor cable fixation. The prestress tensioning and sealing anchor system and the construction method comprise a group hole anchor and a tensioning assembly, wherein the tensioning assembly comprises a bearing frame, a connecting cylinder, an extension steel strand and a tensioning jack, one end of the bearing frame is covered outside the group hole anchor, the other end of the bearing frame is provided with a through hole, one end of the connecting cylinder is fixedly connected with an anchor rope, one end of the extension steel strand is fixedly connected with one end of the connecting cylinder, which is far away from the anchor rope, the other end of the extension steel strand penetrates through the through hole to one side, far away from the group hole anchor, of the bearing frame, the tensioning jack is arranged at one end, far away from the group hole anchor, of the bearing frame, one end of the tensioning jack is propped against the bearing frame, and the other end of the tensioning jack is fixedly connected with the extension steel strand. The prestress stretch-draw sealing anchor system and the construction method can avoid the problem that the first clamping piece falls off.

Description

Prestressed tension anchor system and construction method

Technical Field

The invention relates to the technical field of anchor cable fixing, and in particular to a prestressed tensioning anchor sealing system and a construction method.

Background Art

At present, new structures such as prefabricated structures and wind towers often apply prestress to the beam and column structures of the load-bearing components. Unbonded anchor cables are conventionally used, and group hole anchors are configured at the tensioning ends for construction. The wind tower mixed tower structure also uses unbonded anchor cables in the concrete tower structure, and group hole anchors are configured at the ends to complete the force. After the group hole anchors at the ends of the unbonded anchor cables are tensioned, the main force-bearing mode is to transmit the force through the end anchors. Due to the presence of grease in the unbonded anchor cables' own structural characteristics, the tendons can slide relatively. This structure enhances the flexibility of the structure itself and improves the self-recovery ability of the structure. Especially for the frequent earthquakes in recent years, there are often vibrations that disturb the structure, and this structure can also better adapt to earthquake vibrations.

But at the same time, the stiffness of the structure is also reduced, the seismic resistance of the structure is reduced, and with multiple vibration disturbances on the structure, the anchors at the prestressed ends will become loose, and the structural force will change. The wind power hybrid tower structure also has such problems. The wind tower is a flexible structure, and with the rotation of the fan blades, the structure itself is undergoing micro-frequency vibrations all the time, which has a great impact on the unbonded anchor cables. The anchors at the prestressed ends will also become loose, so secondary tensioning is often required after a long time.

At present, the specifications require that after the anchor cable is tensioned, the reserved length of the anchor cable is about 50mm. The reserved length is short, which is not convenient for secondary tensioning. In addition, since the end of the wind tower mixed tower structure is often equipped with a group hole anchor to complete the force, during the secondary tensioning, the presence of anchor cables in other positions in the group hole anchor will hinder the tensioning jack from reaching the end of the group hole anchor, making it difficult for the tensioning jack to bear the force and making the secondary tensioning work difficult.

Summary of the invention

The purpose of the present invention is to overcome the problems in the prior art and provide a prestressed tensioning anchor system and a construction method that can conveniently achieve secondary tensioning of anchor cables in a group hole anchor configured at the end of a wind tower mixed tower structure.

The prestressed tension anchor sealing system of the present invention comprises a group hole anchor, wherein a plurality of first fixing holes are evenly arranged on the group hole anchor, and a first clip is arranged in the first fixing hole to fix the anchor cable passing through the first fixing hole, and is characterized in that it also comprises a tensioning assembly, wherein the tensioning assembly comprises:

A load-bearing frame, one end of which is covered outside the group hole anchor, and the other end of which is provided with a through hole;

A connecting tube, one end of which is fixedly connected to the anchor cable;

An extended steel strand has one end fixedly connected to an end of the connecting tube away from the anchor cable, and the other end passing through the through hole to a side of the bearing frame away from the group hole anchor;

The tensioning jack is arranged at one end of the load-bearing frame away from the group hole anchor. One end of the tensioning jack is pressed against the load-bearing frame, and the other end is fixedly connected to the extended steel strand.

Preferably, a trumpet tube is pre-embedded in the original concrete structure, and the exposed end of the trumpet tube extends from the inside of the original concrete structure to the surface of the original concrete structure. The side of the group hole anchor away from the limiting plate is in contact with the end face of the exposed end, and each anchor cable passes through the exposed end and passes through the corresponding first fixing hole and the limiting hole in sequence. An annular support is provided on the outer fixed sleeve of the exposed end, and an annular groove is provided on the side of the annular support away from the original concrete structure. The annular groove is sleeved on the outer side of the exposed end, and the shape and size of one end of the bearing frame are adapted to the annular groove so as to be embedded in the annular groove. The through hole is provided at the other end of the bearing frame.

Preferably, the end face of the load-bearing frame away from the group hole anchor is a plane, the end face of the load-bearing frame away from the group hole anchor is parallel to the end face of the group hole anchor, the through hole is arranged on the end face of the load-bearing frame away from the group hole anchor, and the axial centerline of the through hole is perpendicular to the end face of the group hole anchor.

Preferably, the load-bearing frame is conical, and the diameter of one end of the load-bearing frame cover arranged outside the group hole anchor is larger than the diameter of the other end.

Preferably, the connecting tube includes two single-hole anchors and a tube body, the single-hole anchors are each provided with a second fixing hole, the second fixing holes on the two single-hole anchors are concentrically arranged, and each single-hole anchor is provided with a second clip to respectively fix the anchor cable and the extended steel strand, and the tube body includes two connecting arms arranged in parallel, the two connecting arms are connected between the two single-hole anchors and are located on both sides of the second fixing hole symmetrically.

Preferably, a sealing anchor assembly is installed on the exposed end, and the sealing anchor assembly comprises:

The anchor sealing cover has an open end at one end, and the anchor sealing cover is arranged on the outside of the group hole anchor through the open end, and is detachably connected to the exposed end;

A limit plate is located in the anchor sealing cover, one side of the limit plate is in contact with the end face of the group hole anchor, a plurality of limit holes are arranged on the limit plate, the limit holes correspond to the holes on the group hole anchor one by one, each limit hole is concentrically arranged with the corresponding first fixing hole, so that the anchor cable passes through the corresponding first fixing hole and the limit hole in sequence, and the diameter of the limit hole is smaller than the diameter of the corresponding first fixing hole;

The two ends of the pressure spring are respectively fixedly connected to a side of the limit plate away from the group hole anchor and the inside of the anchor cover, so that the limit plate is pressed against the first clamping piece.

Preferably, the elastic force direction of the pressure spring is perpendicular to the end surface of the group hole anchor.

Preferably, the shape and size of the inner side of the opening end and the shape and size of the limiting plate are consistent with the shape and size of the cross section of the group hole anchor.

Preferably, a sealing gasket is sleeved on the outer side of the group hole anchor, and the shape and size of the inner side of the sealing gasket are consistent with the shape and size of the cross section of the group hole anchor.

The construction method of the prestressed tensioned anchor seal system with the anchor seal assembly comprises the following steps:

S1: Installing the group hole anchor: passing each anchor cable through the corresponding first fixing hole on the group hole anchor, and after one side of the group hole anchor is in contact with the exposed end surface, fixing the anchor cable in the corresponding first fixing hole by a first clamp;

S2: Install the anchor cover: make each anchor cable pass through the corresponding limiting holes on the limiting plate, and make the limiting plate fit with the end surface of the group hole anchor, press the anchor cover with force, so that the open end of the anchor cover is sleeved outside the limiting plate and the group hole anchor, and align the corresponding bolt holes on the annular ear plate and the exposed end, and then connect the corresponding bolt holes with fixing bolts to complete the installation and fixation of the anchor cover;

S3: When secondary tensioning is required, first remove the fixing bolts on the lower side, drain the grease in the anchor seal cover, and then remove the fixing bolts on the upper side to remove the anchor seal cover, the limit plate and the pressure spring;

S4: Connect one end of the extended steel strand to the anchor cable through a connecting tube;

S5: Install the load-bearing frame: insert one end of the load-bearing frame into the annular groove, and pass the other end of the extended steel strand through the through hole to the side of the load-bearing frame away from the annular groove;

S6: Install the tensioning jack so that one end of the tensioning jack abuts against the load-bearing frame and the other end bites the extended steel strand;

S7: After the jack is connected to the power supply, check the safety of the on-site operation and start tensioning. When the tensioning length reaches 10cm to 20cm, the tensioning operation can be stopped;

S8: After the tensioning is completed, the tensioning components are removed, and finally step S2 is performed again.

Compared with the prior art, the present invention has at least the following advantages:

The prestressed tensioning anchor sealing system of the present invention can lengthen the force-bearing distance of the anchor by setting a tensioning assembly, connecting the anchor cable with the extended steel strand through a connecting tube, and then setting a load-bearing frame cover outside the group hole anchor, so that the tensioning jack can avoid other anchor cables in the group hole anchor, and tension a single anchor cable, thereby conveniently realizing the secondary tensioning of the anchor cable in the group hole anchor configured at the end of the wind tower mixed tower structure;

At the same time, by setting up the anchor sealing assembly, the pressure spring in the anchor sealing cover is used to press the limit plate against the first clip inside the first fixing hole that can limit the group hole anchor, so as to limit the position of the first clip and keep the first clip flat and in the same plane, thereby improving the stability of the first clip, protecting the anchor cable in the anchor sealing cover, and preventing the first clip from falling off.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the overall structure of the present invention;

FIG2 is a schematic structural diagram of a load-bearing frame of the present invention;

FIG3 is a schematic diagram of a cross-sectional connection structure of a connecting tube of the present invention;

FIG4 is a schematic structural diagram of a sealing and anchoring assembly of the present invention;

FIG. 5 is a schematic diagram of the structure of the limiting plate of the present invention.

Description of reference numerals:

1. Anchor cable; 2. Single-hole anchor; 3. Second clamp; 4. Cylinder body; 5. Extended steel strand; 6. Load-bearing frame; 7. Original concrete structure; 8. Group-hole anchor; 9. Limit plate; 91. Limit hole; 10. Oil pipe; 11. Anchor sealing cover; 111. Annular ear plate; 112. Bolt hole; 12. Pressure spring; 13. Fixing bolt; 14. Exposed end; 141. Annular support; 142. Annular groove; 15. Sealing gasket.

DETAILED DESCRIPTION

The specific implementation of the present invention is described in detail below in conjunction with Figures 1 to 5, but it should be understood that the protection scope of the present invention is not limited by the specific implementation. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

The prestressed tensioning anchor system and construction method provided by the present invention include a group hole anchor 8 and a tensioning assembly. The group hole anchor 8 is evenly provided with a plurality of first fixing holes, and a first clamp is provided in the first fixing hole to fix the anchor cable 1 passing through the first fixing hole. The tensioning assembly includes a bearing frame 6, a connecting tube, an extended steel strand 5 and a tensioning jack. The bearing frame 6 has one end cover arranged outside the group hole anchor 8 and the other end is provided with a through hole. One end of the connecting tube is fixedly connected to the anchor cable 1, and the extended steel strand 5 is provided with a through hole. One end is fixedly connected to the end of the connecting tube away from the anchor cable 1, and the other end passes through the through hole to the side of the load-bearing frame 6 away from the group hole anchor 8. The tensioning jack is arranged at the end of the load-bearing frame 6 away from the group hole anchor 8. One end of the tensioning jack is pressed against the load-bearing frame 6, and the other end is fixedly connected to the extended steel strand 5. Through the installation of the load-bearing frame 6, the anchor cable 1 at other positions in the group hole anchor 8 can be avoided from obstructing the tensioning jack, so that the tensioning jack is supported, which is convenient for secondary tensioning of the anchor cable 1.

As a preferred method, a trumpet tube is pre-embedded in the original concrete structure 7, and the exposed end 14 of the trumpet tube extends from the inside of the original concrete structure 7 to the surface of the original concrete structure 7. The side of the group hole anchor 8 away from the limiting plate 9 is in contact with the end face of the exposed end 14, and each anchor cable 1 passes through the exposed end 14 and passes through the corresponding first fixing hole and the limiting hole 91 in sequence. The outer fixed sleeve of the exposed end 14 is provided with an annular support 141, and an annular groove 142 is provided on the side of the annular support 141 away from the original concrete structure 7. The annular groove 142 is sleeved on the outer side of the exposed end 14, and the shape and size of one end of the bearing frame 6 are adapted to the annular groove 142 so as to be embedded in the annular groove 142. A through hole is provided at the other end of the bearing frame 6. The setting of the annular groove 142 can improve the stability of the bearing frame 6 during secondary tensioning and prevent the bearing frame 6 from slipping.

As a preferred embodiment, the end face of the load-bearing frame 6 away from the annular groove 142 is a plane, the end face of the load-bearing frame 6 away from the annular groove 142 is parallel to the end face of the group hole anchor 8, and the through hole is arranged on the end face of the load-bearing frame 6 away from the annular groove 142, and the axial center line of the through hole is perpendicular to the end face of the group hole anchor 8, which can improve the stress conditions of the load-bearing frame 6 and the tensioning jack, make the force applied to the load-bearing frame 6 and the tensioning jack more stable, and avoid deviation.

As a preferred embodiment, the load-bearing frame 6 is conical, and the diameter of one end of the load-bearing frame 6 that is engaged with the annular groove 142 is larger than the diameter of the other end, which can enhance the load-bearing capacity of the load-bearing frame 6.

As a preferred embodiment, the connecting tube includes two single-hole anchors 2 and a tube body 4. The single-hole anchors 2 are each provided with a second fixing hole. The second fixing holes on the two single-hole anchors 2 are concentrically arranged. Each single-hole anchor 2 is provided with a second clip 3 to fix the anchor cable 1 and the extended steel strand 5 respectively. Specifically, the second clip 3 and the first clip are both a pair of wedge-shaped clips, so that the anchor cable 1 or the extended steel strand 5 can be fixed while resisting the tension brought by the anchor cable 1 or the extended steel strand 5. The tube body 4 includes two connecting arms arranged in parallel. The two connecting arms are connected between the two single-hole anchors 2 and are located on both sides of the second fixing hole symmetrically. The above technical scheme is adopted to facilitate the connection of the anchor cable 1 or the extended steel strand 5 with the corresponding single-hole anchor 2, and the connection is convenient.

In order to achieve secondary tensioning, the prior art uses a sealed anchor cover outside the end anchor, and grease is added inside the anchor cover to protect the reserved steel strand. However, this anchor sealing method is more likely to cause the end anchor to have a clip fall off after being vibrated, so that the anchor may loosen, resulting in the need to increase the inspection frequency and increase the workload of assessing prestress loss and secondary tensioning. For this reason, as a preferred method, an anchor sealing assembly is installed on the exposed end 14, and the anchor sealing assembly includes an anchor sealing cover 11, a limit plate 9 and a pressure spring 12. One end of the anchor sealing cover 11 is an open end. The anchor sealing cover 11 is arranged on the outside of the group hole anchor 8 through the open end, and the outer fixing sleeve of the open end is provided with an annular ear plate 111, and the annular ear plate 111 and the exposed end 14 are provided with corresponding bolt holes 112, so that the corresponding bolt holes 112 are connected by fixing bolts 13. Specifically, the annular ear plate 111 and the exposed end 14 are provided with three bolt holes 112 in an annular array. , one is located on the upper side, and two are located on the upper side, which can facilitate the disassembly and assembly of the anchor cover 11 and the discharge of grease. At the same time, fixing the anchor cover 11 to the exposed end 14 of the trumpet can improve the stability of the anchor cover 11, thereby improving the stability of the limit plate 9 on the first clamp. The limit plate 9 is located in the anchor cover 11. Specifically, the raw material of the limit plate 9 is steel with a thickness of 5mm. One side of the limit plate 9 is in contact with the end face of the group hole anchor 8, and a plurality of limit plates 9 are arranged on the limit plate 9. The limiting holes 91 correspond to the holes on the group hole anchor 8 one by one. Each limiting hole 91 is concentrically arranged with the corresponding first fixing hole, so that the anchor cable 1 passes through the corresponding first fixing hole and the limiting hole 91 in sequence. The diameter of the limiting hole 91 is smaller than the diameter of the corresponding first fixing hole, so that the limiting plate 9 can be pressed against the first clamping piece. The two ends of the pressure spring 12 are respectively fixedly connected to the side of the limiting plate 9 away from the group hole anchor 8 and the anchor cover 11, so as to press the limiting plate 9 against the first clamping piece.

By installing the anchor cover 11 at the exposed end 14 and using the pressure spring 12 in the anchor cover 11, the limit plate 9 is pressed against the first clip inside the first fixing hole that can limit the group hole anchor 8, so as to limit the position of the first clip and keep the first clip flat so that it is in the same plane, thereby preventing the exposed anchor cable 1 from rusting. When the structure is disturbed and the group hole anchor 8 becomes loose, secondary tensioning cannot be performed. In order to achieve secondary tensioning, some existing technologies use a sealed anchor cover 11 to cover the outside of the group hole anchor 8, and add grease in the anchor cover 11 to protect the anchor cable 1, while preventing the first clip in the group hole anchor 8 from falling off, avoiding the possibility of the anchor loosening, improving the stability of the group hole anchor 8, and reducing the number of tensioning times required.

As a preferred method, the elastic force direction of the pressure spring 12 is perpendicular to the end face of the group hole anchor 8, so that the force between the limit plate 9 and the anchor cover 11 is perpendicular to the limit plate 9, avoiding the tilting force of the anchor cover 11 and improving the service life of the anchor cover 11.

As a preferred embodiment, one end of the anchor sealing cover 11 is set as an open end, so that the cover is fixed outside the group hole anchor 8 through the open end. The shape and size of the open end and the shape and size of the limiting plate 9 are consistent with the shape and size of the cross section of the group hole anchor 8, which can improve the installation stability of the anchor sealing cover 11 and the limiting plate 9, thereby better avoiding the problem of loosening and falling off of the first clip.

As a preferred method, a sealing gasket 15 is sleeved on the outside of the group hole anchor 8, and the inner shape and size of the sealing gasket 15 are consistent with the shape and size of the cross section of the group hole anchor 8. Before installing the sealing anchor cover 11, the sealing gasket 15 is installed first, and then the open end of the sealing anchor cover 11 is pressed against the sealing gasket 15, which can improve the sealing effect.

As a preferred method, at least one of the multiple anchor cables 1 is coupled with a grating sensor to form an intelligent steel strand. Specifically, it is made by implanting a fiber Brillouin or fiber Bragg grating sensor element into the anchor cable during its processing and manufacturing process. It is made by replacing one strand in the anchor cable. Each anchor cable is a separate system, which is simple and convenient to use. It can be used together with ordinary anchor cables regardless of position. It has low cost, high precision and strength. One end of the intelligent steel strand located in the anchor sealing cover 11 is connected to a fiber jumper head, which is connected to a fiber demodulator through the fiber jumper head. Specifically, when it is necessary to detect whether secondary tensioning is required, the anchor sealing cover 11 is opened, and then the fiber jumper head is connected to the fiber demodulator for data collection. Through the intelligent steel strand, the stress of the prestress can be observed at any time. When the group hole anchor 8 becomes loose and the loss of the anchor cable 1 increases, the loss of the anchor cable can be measured through the intelligent steel strand. After evaluation, tensioning can be performed again. Especially for wind tower structures, the force measurement of the anchor cable can be carried out without stopping the machine, saving economic costs, and when the force loss of the anchor cable 1 is not serious, the tensioning operation can be omitted, reducing the economic losses caused by blind shutdown.

The construction method of the prestressed tensioned anchor seal system with an anchor seal assembly comprises the following steps:

S1: Installing the group hole anchor 8: Passing each anchor cable 1 through the corresponding first fixing hole on the group hole anchor 8, and after one side of the group hole anchor 8 is in contact with the end surface of the exposed end 14, the anchor cable 1 in the corresponding first fixing hole is fixed by a first clamp;

S2: Install the anchor cover 11: first install the sealing gasket 15, then make each anchor cable 1 pass through the corresponding limiting holes 91 on the limiting plate 9, and make the limiting plate 9 fit with the end surface of the group hole anchor 8, press the anchor cover 11 with force, so that the open end of the anchor cover 11 is sleeved outside the limiting plate 9 and the group hole anchor 8, the pressure spring 12 is compressed, and the corresponding bolt holes 112 on the annular ear plate 111 and the exposed end 14 are aligned, and then the corresponding bolt holes 112 are connected by the fixing bolts 13 to complete the installation and fixation of the anchor cover 11. Specifically, the anchor cover 11 is connected with the oil pipe 10, so that grease is injected into the anchor cover 11 through the oil pipe 10;

S3: When secondary tensioning is required, first remove the fixing bolts 13 on the lower side to discharge the grease in the anchor seal cover 11, and then remove the fixing bolts 13 on the upper side to remove the anchor seal cover 11, the limit plate 9 and the pressure spring 12;

S4: Connect one end of the extended steel strand 5 to the anchor cable 1 through a connecting tube;

S5: Install the load-bearing frame 6: insert one end of the load-bearing frame 6 into the annular groove 142, and pass the other end of the extended steel strand 5 through the through hole to the side of the load-bearing frame 6 away from the annular groove 142;

S6: Install the tensioning jack so that one end of the tensioning jack abuts against the load-bearing frame 6 and the other end bites the extended steel strand 5;

S7: After the jack is connected to the power supply, check the safety of the on-site operation and start tensioning. When the tensioning length reaches 10cm to 20cm, the tensioning operation can be stopped;

S8: After the tensioning is completed, the tensioning components are removed, and finally step S2 is performed again.

In the description of the present invention, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect" and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims (10)

1. The utility model provides a prestressing force stretch-draw seals anchor system, includes crowd hole ground tackle (8), evenly is equipped with a plurality of first fixed orificess on crowd hole ground tackle (8), is equipped with first clamping piece in the first fixed orificess to fix anchor rope (1) that pass from first fixed orificess, its characterized in that still includes stretch-draw subassembly, stretch-draw subassembly includes:

One end of the bearing frame (6) is covered outside the group hole anchor (8), and the other end is provided with a through hole;

one end of the connecting cylinder is fixedly connected with the anchor cable (1);

One end of the extension steel strand (5) is fixedly connected with one end of the connecting cylinder, which is far away from the anchor cable (1), and the other end of the extension steel strand penetrates through the through hole to one side, which is far away from the group hole anchorage device (8), of the bearing frame (6);

And the tensioning jack is arranged at one end of the bearing frame (6) far away from the group hole anchor (8), one end of the tensioning jack is propped against the bearing frame (6), and the other end of the tensioning jack is fixedly connected with the extension steel strand (5).

2. The prestress tensioning seal anchor system as claimed in claim 1, wherein a horn pipe is embedded in the original concrete structure (7), a bare end (14) of the horn pipe extends out of the original concrete structure (7) to the surface of the original concrete structure (7), one face of the group hole anchor (8) away from the limiting plate (9) is attached to the end face of the bare end (14), each anchor cable (1) penetrates out of the bare end (14) and sequentially penetrates through a corresponding first fixing hole and a corresponding limiting hole (91), an annular support (141) is fixedly sleeved on the outer side of the bare end (14), an annular groove (142) is formed in a side face, away from the original concrete structure (7), of the annular support (141) and sleeved on the outer side of the bare end (14), one end of the bearing frame (6) is matched with the annular groove (142) in shape and size so as to be embedded in the annular groove (142), and the other end of the through hole is arranged on the other end of the bearing frame (6).

3. The prestress tensioning seal anchor system according to claim 1, wherein an end face of the bearing frame (6) away from the group hole anchor (8) is a plane, an end face of the bearing frame (6) away from the group hole anchor (8) is parallel to an end face of the group hole anchor (8), the through hole is formed in an end face of the bearing frame (6) away from the group hole anchor (8), and an axis line of the through hole is perpendicular to the end face of the group hole anchor (8).

4. The prestress tension sealing anchor system as claimed in claim 1, wherein the bearing frame (6) is conical, and one end diameter of the bearing frame (6) covered outside the group hole anchor (8) is larger than the other end diameter.

5. The prestress tensioning and sealing anchor system according to claim 1, wherein the connecting cylinder comprises two single-hole anchors (2) and a cylinder body (4), second fixing holes are formed in the single-hole anchors (2), the second fixing holes in the two single-hole anchors (2) are concentrically arranged, second clamping pieces (3) are arranged in each single-hole anchor (2) to fix the anchor cable (1) and the extension steel strand (5) respectively, the cylinder body (4) comprises two connecting arms which are arranged in parallel, and the two connecting arms are connected between the two single-hole anchors (2) and are located on two sides of the symmetry of the second fixing holes.

6. The prestressed tension sealing system according to claim 2, wherein said exposed end (14) has mounted thereon a sealing assembly comprising:

One end of the anchor sealing cover (11) is an open end, and the anchor sealing cover (11) is covered on the outer side of the group hole anchor (8) through the open end and is detachably connected with the exposed end (14);

The limiting plates (9) are positioned in the anchor sealing cover (11), one surface of each limiting plate (9) is attached to the end surface of the group hole anchor (8), a plurality of limiting holes (91) are distributed on each limiting plate (9), the limiting holes (91) are in one-to-one correspondence with the holes on the group hole anchor (8), and each limiting hole (91) is concentrically arranged with the corresponding first fixing hole, so that the anchor cable (1) sequentially passes through the corresponding first fixing hole and the corresponding limiting hole (91), and the diameter of each limiting hole (91) is smaller than that of the corresponding first fixing hole;

the two ends of the pressure spring (12) are respectively and fixedly connected with one surface of the limiting plate (9) far away from the group hole anchor (8) and the inside of the anchor sealing cover (11), so that the limiting plate (9) is propped against the first clamping piece.

7. The prestress tensioning seal anchor system according to claim 6, wherein the spring force direction of the pressure spring (12) is perpendicular to the end face of the group hole anchor (8).

8. The prestress tension sealing anchor system as claimed in claim 6, wherein the shape and the size of the inner side of the open end and the shape and the size of the limiting plate (9) are consistent with the shape and the size of the cross section of the group hole anchor (8).

9. The prestress tensioning seal anchor system as claimed in claim 6, wherein a sealing gasket (15) is sleeved outside the group hole anchor (8), and the inner side of the sealing gasket (15) is identical in shape and size with the cross section of the group hole anchor (8).

10. The method for constructing a prestressed stretch-draw anchor system according to claim 6, comprising the steps of:

S1: mounting group hole anchorage (8): each anchor cable (1) respectively passes through the corresponding first fixing holes on the group hole anchors (8), and after one surface of the group hole anchors (8) is attached to the end surface of the exposed end (14), the anchor cable (1) in the corresponding first fixing holes is fixed through the first clamping piece;

S2: installing an anchor sealing cover (11): each anchor rope (1) passes through each corresponding limiting hole (91) on the limiting plate (9), the limiting plate (9) is attached to the end face of the group hole anchorage device (8), the anchor sealing cover (11) is pressed forcefully, the opening end of the anchor sealing cover (11) is sleeved outside the limiting plate (9) and the group hole anchorage device (8), the corresponding bolt holes (112) on the annular lug plate (111) and the exposed end (14) are aligned, and then the corresponding bolt holes (112) are connected through the fixing bolts (13), so that the installation and fixation of the anchor sealing cover (11) are completed;

S3: when secondary tensioning is needed, the fixing bolts (13) positioned at the lower side are removed firstly, grease in the anchor sealing cover (11) is discharged, and then the fixing bolts (13) positioned at the upper side are removed, so that the anchor sealing cover (11), the limiting plate (9) and the pressure springs (12) are removed;

S4: one end of an extension steel strand (5) is connected with an anchor cable (1) through a connecting cylinder;

S5: and (3) installing a bearing frame (6): one end of the bearing frame (6) is embedded in the annular groove (142), and the other end of the extension steel strand (5) penetrates through the through hole to one side, far away from the annular groove (142), of the bearing frame (6);

s6: installing a tensioning jack, wherein one end of the tensioning jack is abutted against the bearing frame (6), and the other end of the tensioning jack bites the extension steel strand (5);

S7: after the jack is connected with a power supply, the operation safety of the site is checked, the tensioning is started, and when the tensioning length reaches 10 cm-20 cm, the tensioning operation can be stopped;

s8: and after the tensioning is finished, removing the tensioning assembly, and finally, performing step S2 again.