阅读说明：本技术 基于psb精轧螺纹钢的扩大头抗浮锚杆预应力施加方法 (PSB finish rolling deformed steel bar-based expanded head anti-floating anchor rod prestress application method ) 是由 高晓峰 罗东林 侯会军 廖宏业 黄海 任东兴 于 2021-09-03 设计创作，主要内容包括：本发明属于PSB精轧螺纹钢预应力抗浮锚杆技术领域,公开了一种基于PSB精轧螺纹钢的扩大头抗浮锚杆预应力施工方法,为了解决采用穿心千斤顶无法满足PSB精轧螺纹钢的扩大头抗浮锚杆所需预应力的问题。本发明包括：(1)浇筑垫层,(2)在PSB精轧螺纹钢上套设预应力配套锚板和预应力配套锚头；(3)施加预应力的步骤,包括：(3.1)在配套锚头的外围套设钢梁；然后将配套锚头连接在PSB精轧螺纹钢上；(3.2)在垫层上放置多个垫板,并且每一个垫板上放置一千斤顶,千斤顶的上端与钢梁相互接触,顶升千斤顶对PSB精轧螺纹钢进行施加预应力；(3.3)锁紧预应力配套锚头完成预应力的施加。(The invention belongs to the technical field of PSB finish rolling deformed steel bar prestressed anti-floating anchor rods, and discloses a PSB finish rolling deformed steel bar based expanded head anti-floating anchor rod prestressed construction method, aiming at solving the problem that the prestress required by the PSB finish rolling deformed steel bar expanded head anti-floating anchor rod cannot be met by adopting a center-penetrating jack. The invention comprises the following steps: (1) pouring a cushion layer, (2) sleeving a prestress matched anchor plate and a prestress matched anchor head on the PSB finish-rolled deformed steel bar; (3) a step of prestressing, comprising: (3.1) sleeving a steel beam on the periphery of the matched anchor head; then connecting the matched anchor head to PSB finish-rolled deformed steel bar; (3.2) placing a plurality of base plates on the cushion layer, placing a jack on each base plate, enabling the upper end of each jack to be in contact with the steel beam, and applying prestress to the PSB finish rolling deformed steel bars by the aid of the jacking jacks; and (3.3) locking the prestress matched anchor head to complete the application of prestress.)

1. The PSB finish rolling deformed steel bar-based expanded head anti-floating anchor rod prestress application method is characterized by comprising the following steps of:

(1) pouring a cushion layer;

(2) sequentially sleeving a prestress matching anchor plate and a prestress matching anchor head on the PSB finish-rolled deformed steel bar positioned above the cushion layer from bottom to top;

(3) a step of prestressing, said step of prestressing comprising:

(3.1) sleeving a steel beam in a linear shape, a cross shape or a meter shape on the periphery of the matched anchor head, wherein the steel beam is provided with a central hole matched with the shape of the matched anchor head so that the steel beam can be sleeved on the periphery of the matched anchor head; then connecting the matched anchor head on PSB finish rolling deformed steel bar in a threaded manner;

(3.2) placing a plurality of base plates on the cushion layer, placing a jack on each base plate, enabling the lower end of each jack to be in contact with each base plate, enabling the upper end of each jack to be in contact with the steel beam, and enabling the jacking jacks to apply pressure to the steel beams so as to apply prestress to the PSB finish rolling deformed steel bars until the applied prestress meets the design requirement;

and (3.3) after the step (3.2) is completed, locking the prestress matching anchor head to complete the application of prestress.

2. The PSB finish-rolled deformed steel bar-based enlarged footing anti-floating anchor pre-stress application method of claim 1, wherein the number of the jacks corresponds to the structure of the steel beam, the jacks are uniformly distributed below the steel beam, and when the steel beam is in a shape of a straight line, the number of the jacks is 2; when the steel beam is in a cross shape, the number of the jacks is 4; when the girder steel is "rice" word form, the quantity of jack is 6.

3. The PSB finish-rolled deformed steel bar-based enlarged head anti-floating anchor prestress application method according to claim 1 or 2, wherein a center hole of the steel beam is a wedge-shaped hole.

4. The PSB finish-rolled deformed steel bar-based enlarged head anti-floating anchor prestress application method of claim 3, further comprising a step of removing the steel beam after the step of applying the prestress is completed, wherein the step of removing the steel beam comprises the steps of:

(1) rotating the steel beam and driving the matched anchor head to rotate, so that the steel beam and the matched anchor head are separated from the PSB finish rolling deformed steel bar;

(2) taking down the steel beam from the matched anchor head;

(3) after the matched anchor plate is sleeved on the PSB finish-rolled deformed steel bar, the matched anchor head is sleeved again.

5. The PSB finish-rolled deformed steel bar-based enlarged footing anti-floating anchor rod prestress application method of claim 1, wherein an anchor pier with the upper end larger than the lower end is poured on the cushion layer corresponding to the center of the anchor hole, the lower end of the anchor pier is larger than or equal to the diameter of the anchor hole, the center of the anchor pier corresponds to the center of the anchor hole, the lower end of the PSB finish-rolled deformed steel bar penetrates through the anchor pier and extends into the anchor hole, a spiral rib is further arranged in the anchor pier, and the middle of the spiral rib is provided with a center hole for the PSB finish-rolled deformed steel bar of the anti-floating anchor rod to penetrate through.

6. The PSB finish-rolled deformed steel bar-based expanded head anti-floating anchor rod prestress application method according to claim 5, wherein at least two diagonal reinforcing bars are connected to the periphery of the spiral reinforcing bar, one ends of the diagonal reinforcing bars are connected with the lower end of the spiral reinforcing bar, and the other ends of the diagonal reinforcing bars are connected with horizontal bars implanted into the horizontal section of the cushion layer.

7. The PSB finish-rolled deformed steel bar-based enlarged head anti-floating anchor prestress application method according to claim 6, wherein the diagonal reinforcing steel bars are symmetrically connected to the periphery of the spiral rib.

8. The PSB finish-rolled deformed steel bar-based enlarged footing anti-floating anchor rod prestress application method of claim 7, wherein the upper end of the PSB finish-rolled deformed steel bar passes through the center hole of the spiral rib and out of the cushion layer and is sleeved with a prestress matching anchor plate, the prestress matching anchor plate is provided with a prestress matching anchor head, and the lower end surface of the prestress matching anchor plate is in contact with the upper end surface of the cushion layer.

Technical Field

The invention belongs to the technical field of PSB finish rolled deformed steel bar prestressed anti-floating anchor rods, and particularly relates to a PSB finish rolled deformed steel bar based expanded head anti-floating anchor rod prestress application method.

Background

The anti-floating anchor rod is a structural member arranged for resisting upward displacement of a building on the anti-floating anchor rod, is related to the height and change of an underground water level, and is opposite to the stress direction of a compression-resistant pile.

Anti-floating anchor includes ordinary anti-floating anchor and enlarged footing anti-floating anchor, and in order to improve the anti-floating ability of anti-floating anchor, enlarged footing anti-floating anchor has appeared, and enlarged footing anti-floating anchor is with the biggest difference of ordinary anti-floating anchor: the bottom of the anchor hole is provided with the enlarged head, and an enlarged head section is formed at the bottom of the anchor hole after pouring is finished, so that the anti-pulling capacity of the anti-floating anchor rod is improved. For example, the patent with application number 201220060959.0 discloses a bottom-expanding anti-floating anchor rod, which comprises a metal corrugated pipe penetrating through a waterproof bottom plate, wherein the metal corrugated pipe extends into the lower end part of an anchor rod hole at the lower part of the waterproof bottom plate, and the lower end part of the anchor rod hole is a rod end expanding head; a steel sleeve is embedded outside the metal corrugated pipe in the waterproof bottom plate; the metal corrugated pipe is penetrated with a steel strand, the upper end of the steel strand is fixed on the anchorage device, the lower end of the steel strand is anchored on the anchoring plate in the rod end expansion head, and the anchoring plate is arranged on the anchoring head; and a secondary grouting guide pipe is arranged between the metal corrugated pipe and the steel sleeve.

With the advent of PSB finish-rolled deformed steel bar anti-floating anchors, there are more and more PSB finish-rolled deformed steel bar anti-floating anchors, for example, patent application No. 202010088483.0 discloses a prestressed anti-floating anchor, which includes an anchor hole opened in a soil body, the anchor hole includes an enlarged head section and a non-enlarged head section, the diameter of the enlarged head section is larger than that of the non-enlarged head section, PSB finish-rolled deformed steel bar is arranged in the anchor hole, a grouting body is poured between the anchor hole and the PSB finish-rolled deformed steel bar, the lower end of the PSB finish-rolled deformed steel bar passes through the non-enlarged head section and the enlarged head section in sequence and is placed at the bottom of the enlarged head section, and the upper end of the PSB finish-rolled deformed steel bar passes through the non-enlarged head section and is located in the foundation of a building; and an anchor plate is arranged at the top of the PSB finish-rolled deformed steel bar.

The existing prestressed anti-floating anchor rod based on PSB finish-rolled deformed steel bars utilizes a center-penetrating jack to conduct prestress tensioning so that the prestress can reach the design requirement, however, the popularization of the expanded head anti-floating anchor rod based on PSB finish-rolled deformed steel bars greatly improves the prestress applied by the expanded head anti-floating anchor rod based on PSB finish-rolled deformed steel bars, and the center-penetrating jack cannot meet the prestress application of the expanded head anti-floating anchor rod based on PSB finish-rolled deformed steel bars due to limited acting force. Meanwhile, when the center-penetrating jack is used, the problem of complicated steps exists, so that the problem of long prestress application period exists when the center-penetrating jack is adopted; meanwhile, when the prestress is applied by using the center-penetrating jack, the PSB finish-rolled deformed steel bar needs to penetrate the center-penetrating jack, so that the prestress cannot be applied to the PSB finish-rolled deformed steel bar by using a plurality of jacks. Therefore, how to conveniently and quickly apply prestress to the enlarged footing anti-floating anchor rod based on PSB finish-rolled deformed steel bars becomes a problem which needs to be solved in the field urgently.

Meanwhile, after the existing PSB finish-rolled deformed steel bar prestressed anti-floating anchor rod is prestressed, a cushion layer (formed by pouring concrete and not in the same concept with a mattress cushion layer) mainly comprises the steps of 1 facilitating construction and paying-off and supporting of a foundation template, 2 ensuring the effective position of a foundation bottom plate rib, controlling a protective layer well to prevent the bottom rib and soil from being polluted, 3 facilitating the bottom surface of the foundation to be used as an anti-corrosion layer, 4 leveling, compensating for errors of earth excavation by adjusting the thickness, enabling the bottom plate to be stressed on a plane, avoiding waste of high-grade concrete of the foundation, and 5 improving the effects of a waterproof base layer, drainage and freezing prevention of the high-grade concrete on the foundation) is easy to damage under the pulling effect of the anchor rod, so that the effect of the cushion layer is lost.

Disclosure of Invention

The invention provides a PSB finish-rolled deformed steel bar-based expanded head anti-floating anchor rod prestress application method for solving the problem that prestress required by an expanded head anti-floating anchor rod of PSB finish-rolled deformed steel bar cannot be met by adopting a center-penetrating jack, can meet the prestress requirement of the expanded head anti-floating anchor rod of PSB finish-rolled deformed steel bar, and has the characteristics of convenience and quickness in construction.

In order to solve the technical problem, the technical scheme adopted by the invention is as follows:

the PSB finish rolling deformed steel bar-based expanded head anti-floating anchor rod prestress application method is characterized by comprising the following steps of:

(1) pouring a cushion layer;

(2) sequentially sleeving a prestress matching anchor plate and a prestress matching anchor head on the PSB finish-rolled deformed steel bar positioned above the cushion layer from bottom to top;

(3) a step of prestressing, said step of prestressing comprising:

(3.1) sleeving a steel beam in a linear shape, a cross shape or a meter shape on the periphery of the matched anchor head, wherein the steel beam is provided with a central hole matched with the shape of the matched anchor head so that the steel beam can be sleeved on the periphery of the matched anchor head; then connecting the matched anchor head on PSB finish rolling deformed steel bar in a threaded manner;

(3.2) placing a plurality of base plates on the cushion layer, placing a jack on each base plate, enabling the lower end of each jack to be in contact with each base plate, enabling the upper end of each jack to be in contact with the steel beam, and enabling the jacking jacks to apply pressure to the steel beams so as to apply prestress to the PSB finish rolling deformed steel bars until the applied prestress meets the design requirement;

and (3.3) after the step (3.2) is completed, locking the prestress matching anchor head to complete the application of prestress.

In some embodiments, the number of the jacks corresponds to the structure of the steel beam, the jacks are uniformly distributed below the steel beam, and when the steel beam is in a shape of a Chinese character 'yi', the number of the jacks is 2; when the steel beam is in a cross shape, the number of the jacks is 4; when the girder steel is "rice" word form, the quantity of jack is 6.

In some embodiments, the central bore of the steel beam is a wedge bore.

In some embodiments, after the step of prestressing is completed, there is further a step of removing the steel beam, the step of removing the steel beam including:

(1) rotating the steel beam and driving the matched anchor head to rotate, so that the steel beam and the matched anchor head are separated from the PSB finish rolling deformed steel bar;

(2) taking down the steel beam from the matched anchor head;

(3) after the matched anchor plate is sleeved on the PSB finish-rolled deformed steel bar, the matched anchor head is sleeved again.

In some embodiments, an anchor pier with an upper end larger than a lower end is poured on the cushion layer corresponding to the center of the anchor hole, the size of the lower end of the anchor pier is larger than or equal to the diameter of the anchor hole, the center of the anchor pier corresponds to the center of the anchor hole, the lower end of the PSB finish-rolled deformed steel bar penetrates through the anchor pier and extends into the anchor hole, a spiral rib is further arranged in the anchor pier, and the middle of the spiral rib is provided with a central hole for the PSB finish-rolled deformed steel bar of the anti-floating anchor rod to penetrate through.

In some embodiments, at least two diagonal reinforcements are connected to the periphery of the spiral reinforcement, one end of each diagonal reinforcement is connected to the lower end of the spiral reinforcement, and the other end of each diagonal reinforcement is connected to a horizontal reinforcement implanted in the horizontal section of the cushion layer.

In some embodiments, the diagonal draw bars are symmetrically connected to the periphery of the spiral bars.

In some embodiments, the upper end of the PSB finish-rolled deformed steel bar passes through the central hole of the spiral rib and out of the cushion layer and is sleeved with a pre-stressed mating anchor plate provided with a pre-stressed mating anchor head, and the lower end surface of the pre-stressed mating anchor plate is in contact with the upper end surface of the cushion layer.

Compared with the prior art, the invention has the following beneficial effects:

compared with the conventional mode of adopting a through jack, the method for applying the prestress to the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar can greatly increase the magnitude of the prestress to be applied, and solves the problem that the prestress required by the design cannot be applied to the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar by the through jack in the prior art, so that the prestress of the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar can meet the design requirement.

Compared with the prior art that the method applies prestress to PSB finish rolling deformed steel bars by adopting a through jack, the method has the characteristics of convenience and quickness, and can greatly improve the prestress application speed so as to reduce the construction period.

According to the invention, the anchor piers corresponding to the anchor hole positions are arranged in the middle of the cushion layer, and the spiral bars are arranged in the anchor piers, so that the anchor piers can provide good support when prestress is applied to PSB finish rolling deformed steel bars, and the spiral bars and the diagonal draw bars can restrict horizontal deformation of anchor pier concrete, thereby greatly improving the overall strength of the anchor piers and avoiding shear damage caused by insufficient shear strength of concrete (cushion layer). Through when exerting prestressing force, the effort that prestressed anchorage board fed back to the anchor block passes through the effect of spiral muscle, diagonal reinforcement and horizontal muscle and concreting, progressively transmits whole bed course with the concentrated atress of anchor block part to avoided the easy problem of damaging of bed course, avoided the prestressing force loss's that brings because of the bed course damage problem simultaneously. And the damage of the cushion layer can directly result in the loss of the applied prestress, so that the prestress of the anti-floating anchor rod cannot meet the design requirement, and a larger potential safety hazard is caused.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the invention when prestress is applied to an enlarged footing anti-floating anchor rod based on PSB finish rolled deformed steel bar;

FIG. 2 is a schematic top view of an embodiment of the present invention illustrating the connection of a steel beam to an anchor head;

FIG. 3 is a schematic longitudinal cross-sectional view of one embodiment of the present invention as a steel beam is connected to an anchor head;

FIG. 4 is a schematic structural diagram of another embodiment of the present invention when prestressing is performed by using a jack;

FIG. 5 is a schematic view of a blanket of the present invention;

FIG. 6 is a schematic view showing a partial structure of a PSB finish-rolled deformed steel bar of the present invention when it is extended into an anchor eye;

the labels in the figure are: 1. The steel plate comprises a cushion layer, 101, anchor piers, 102, spiral ribs, 103, diagonal draw steel bars, 104, horizontal ribs, 2, PSB finish rolling deformed steel bars, 3, a prestress matched anchor plate, 4, a prestress matched anchor head, 5, a matched anchor head, 6, a steel beam, 7, a jack, 8, a backing plate, 9, a matched backing plate, 10, an anchor hole, 1001, a non-expanded head section, 1002, an expanded head section, 11, an anticorrosive sleeve, 12, a foundation or water-resistant plate, 13, a bearing body, 14 and a flexible sealing ring.

Detailed Description

The present invention will be further described with reference to the following examples, which are intended to illustrate only some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, other embodiments used by those skilled in the art without any creative effort belong to the protection scope of the present invention.

With reference to the attached drawings 1 to 4, the invention discloses a PSB finish rolling deformed steel bar-based expanded head anti-floating anchor rod prestress application method, which comprises the following steps:

(1) pouring the cushion layer 1; wherein the cushion layer is formed by pouring concrete. Before the cushion layer 1 is poured, an enlarged footing anti-floating anchor rod based on PSB finish rolling deformed steel bar needs to be constructed. Wherein, the construction is based on expanded footing anti-floating anchor rod of PSB finish rolling screw-thread steel mainly includes:

firstly, positioning a drilling machine: aligning to hole positions, generally adjusting the angle according to design requirements, wherein the deviation is less than or equal to 5 cm;

II, casing pipe drilling: the design depth of the casing is equal to the depth of the non-enlarged head section 1001 of the anchor eye 10; that is, anchor hole 10 includes a non-enlarged head section 1001 and an enlarged head section 1002, the diameter of enlarged head section 1002 being greater than the diameter of non-enlarged head section 1001;

third, reaming (i.e. drilling the enlarged head section 1002 of the anchor hole)

A drill rod is put to the bottom of the hole, whether the depth of the drill rod is consistent with the depth of the casing is checked, the requirement is that the depth of the drill rod is more than or equal to the depth of the casing, and otherwise, the number of the casings and the number of the drill rods need to be checked until the requirements are met;

the first section of hole expanding comprises the following operation steps: drilling a pilot hole, lifting a drill rod after a section of drill rod is bottomed, reaming from top to bottom, reaming a casing pipe to depth from bottom to top after a section of drill rod is bottomed, pushing the section of drill rod forward, installing a second section of drill rod, performing second section of reaming, and the like until the reaming is finished;

reaming; connecting a high-pressure water tap with cement slurry, detecting the mixing ratio of the slurry, expanding the hole from bottom to top from the bottom of the hole, lifting to the depth of the casing pipe, namely stopping, recording the use amount of the slurry, recording whether the hole opening returns the slurry or not, and the like;

fourthly, taking out the drill rod and the anchor (PSB finish rolling deformed steel bar 2 of the invention), and pulling out the sleeve;

and fifthly, grouting, and finishing construction (if grouting is needed) of the expanded head anti-floating anchor rod based on PSB finish rolling deformed steel bars.

The construction process steps of the enlarged footing anti-floating anchor rod based on the PSB finish rolling deformed steel bar belong to the prior art, and can be understood and appreciated by those skilled in the art, and are not described herein again.

(2) Sequentially sleeving a prestress matched anchor plate 3 and a prestress matched anchor head 4 on the PSB finish-rolled deformed steel bar 2 positioned above the cushion layer 1 from bottom to top;

(3) a step of prestressing, said step of prestressing comprising:

(3.1) sleeving a steel beam 6 in a straight shape, a cross shape or a meter shape on the periphery of the matched anchor head 5, wherein the steel beam 6 is provided with a central hole matched with the shape of the matched anchor head 5 so that the steel beam 6 can be sleeved on the periphery of the matched anchor head 5; and then the matched anchor head 5 is connected on the PSB finish-rolled deformed steel bar 2 in a threaded mode. Wherein the matched anchor head 5 is provided with a threaded through hole matched with the PSB finish rolled deformed steel bar 2; because the steel beam 6 is sleeved on the periphery of the matched anchor head 5, the matched anchor head 5 is connected to the PSB finish-rolled deformed steel bar in a threaded manner, and meanwhile, the steel beam 6 is also connected to the PSB finish-rolled deformed steel bar 2 through the matched anchor head 5;

(3.2) placing a plurality of base plates 8 on the cushion layer 1, placing a jack 7 on each base plate, enabling the lower end of each jack 7 to be in contact with the corresponding base plate 8, enabling the upper end of each jack 7 to be in contact with the corresponding steel beam 6, and enabling the jack 7 to apply pressure to the corresponding steel beam 6 so as to apply prestress to the PSB finish-rolled deformed steel bar 2 until the applied prestress meets the design requirement; wherein, preferably, a backing plate 8 is also arranged between the jack 7 and the steel beam 6.

(3.3) after the step (3.2) is completed, locking the prestress matching anchor head 4 to complete the application of prestress.

With reference to fig. 2 to 4, in some embodiments, the number of the jacks 7 corresponds to the structure of the steel beam 6, and the jacks 7 are uniformly distributed below the steel beam 6, and when the steel beam 6 is in a shape of a straight line, the number of the jacks 7 is 2; when the steel beam 6 is in a cross shape, the number of the jacks 7 is 4; when the steel beam 6 is in a shape like a Chinese character 'mi', the number of the jacks 7 is 6.

In some embodiments, the central hole of the steel beam 6 is a wedge-shaped hole. Therefore, the steel beam 6 is directly sleeved on the matched anchor head 5 by utilizing the shape of the wedge-shaped hole, and the steel beam can be sleeved on the matched anchor head 5 along the direction from bottom to top; when the steel beam 6 needs to be taken down, the steel beam 6 is directly knocked from top to bottom.

In some embodiments, after the step of prestressing is completed, there is further a step of removing the steel beam 6, said step of removing the steel beam comprising:

(1) rotating the steel beam 6 and driving the matched anchor head 5 to rotate, so that the steel beam 6 and the matched anchor head 5 are separated from the PSB finish-rolled deformed steel bar 2;

(2) taking down the steel beam 6 from the matched anchor head 5;

(3) after the matched anchor plate 9 is sleeved on the PSB finish-rolled deformed steel bar 2, the matched anchor head 5 is sleeved again.

With reference to fig. 5 and fig. 6, an anchor pier 101 with an upper end size larger than a lower end size is poured at a position of the cushion layer 1 corresponding to the center of the anchor hole 10, the lower end size of the anchor pier 101 is larger than or equal to the diameter of the anchor hole 10, the center of the anchor pier 101 corresponds to the center of the anchor hole 10, wherein the anchor pier 101 can be in a circular truncated cone shape, a prismatic shape or the like, for convenience of construction, as a preferred mode of the invention, the anchor pier 101 is in a circular truncated cone shape with a large upper end and a small lower end, the lower end of the PSB finish-rolled deformed steel bar 2 penetrates through the anchor pier 101 and extends into the anchor hole 10, a spiral rib 102 is further arranged in the anchor pier 101, and the middle of the spiral rib 102 is provided with a central hole for the PSB finish-rolled deformed steel bar 2 to penetrate through.

In some embodiments, at least two diagonal reinforcements 103 are connected to the periphery of the spiral reinforcement 102, one end of each diagonal reinforcement 103 is connected to the lower end of the spiral reinforcement 102, and the other end of each diagonal reinforcement 103 is connected to a horizontal reinforcement 104 embedded in the horizontal section of the cushion layer 1.

In a preferred embodiment of the present invention, the diagonal reinforcement 103 is disposed along a direction parallel to the outer surface of the anchor pier 101, that is, the diagonal reinforcement 103 is disposed along the slope of the outer surface of the anchor pier 101. The stress of the diagonal reinforcing steel bars 103 and the anchor pier 101 is more uniform, and the bearing capacity is further improved.

In some embodiments, to improve the uniformity of the force, the diagonal draw-bars 103 are symmetrically connected to the periphery of the spiral ribs 102.

In some embodiments, the upper end of the PSB finish-rolled deformed steel bar 2 passes through the central hole of the spiral rib 102 and out of the cushion layer 1 and is sleeved with a pre-stressed mating anchor plate 3, the pre-stressed mating anchor rod 3 is provided with a pre-stressed mating anchor head 4, and the lower end surface of the pre-stressed mating anchor plate 3 is in contact with the upper end surface of the cushion layer 1.

In some embodiments, a foundation or water-resistant plate 12 is further cast above the cushion layer 1, and the pre-stressed mating anchor plate 3 and the pre-stressed mating anchor head 5 are positioned in the foundation or water-resistant plate 12.

With reference to fig. 6, the anchor hole 10 of the present invention comprises a non-enlarged head 1001 and an enlarged head 1002, wherein the enlarged head 1002 indicates that the anchor hole 10 extends into the bearing layer of the formation, and the diameter of the enlarged head 1002 is larger than the diameter of the non-enlarged head 1001; the lower end of the PSB finish rolling deformed steel bar 2 penetrates through the anchor pier 101 to extend into the anchor hole 10 and is poured between the anchor hole 10 and the lower end of the PSB finish rolling deformed steel bar to form a grouting anchoring body.

In some embodiments, a plurality of supporting bodies 13 are sleeved on the periphery of the PSB finish-rolled deformed steel bar 2 in the enlarged head section 1002, an anticorrosive sleeve 11 is sleeved on the periphery of the PSB finish-rolled deformed steel bar 2 between the uppermost supporting body 13 and the prestressed supporting anchor plate 3, and the anticorrosive sleeve 11 is filled with anticorrosive grease; the lower end of the corrosion-resistant sleeve 11 is also provided with a flexible sealing ring 14 for preventing the escape of corrosion-resistant grease. Through setting up anticorrosive sleeve pipe 11, filling anticorrosive grease and flexible sealing ring 14, be convenient for carry out anticorrosion protection to PSB finish rolling screw-thread steel 2, improve the life of anti-floating anchor rod.

Compared with the conventional mode of adopting a through jack, the method for applying the prestress to the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar can greatly increase the magnitude of the prestress to be applied, and solves the problem that the prestress required by the design cannot be applied to the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar by the through jack in the prior art, so that the prestress of the expanded head anti-floating anchor rod based on the PSB finish rolled deformed steel bar can meet the design requirement.

Compared with the prior art that the method applies prestress to PSB finish rolling deformed steel bars by adopting a through jack, the method has the characteristics of convenience and quickness, and can greatly improve the prestress application speed so as to reduce the construction period.

According to the invention, the anchor piers corresponding to the anchor hole positions are arranged in the middle of the cushion layer, and the spiral bars are arranged in the anchor piers, so that the anchor piers can provide good support when prestress is applied to PSB finish rolling deformed steel bars, and the spiral bars and the diagonal draw bars can restrict horizontal deformation of anchor pier concrete, thereby greatly improving the overall strength of the anchor piers and avoiding shear damage caused by insufficient shear strength of concrete (cushion layer). Through when exerting prestressing force, the effort that prestressed anchorage board fed back to the anchor block passes through the effect of spiral muscle, diagonal reinforcement and horizontal muscle and concreting, progressively transmits whole bed course with the concentrated atress of anchor block part to avoided the easy problem of damaging of bed course, avoided the prestressing force loss's that brings because of the bed course damage problem simultaneously. And the damage of the cushion layer can directly result in the loss of the applied prestress, so that the prestress of the anti-floating anchor rod cannot meet the design requirement, and a larger potential safety hazard is caused.