CN111395337A

CN111395337A - Prefabricated combined assembled anti-floating tensile prestressed anchor rod piece and construction method thereof

Info

Publication number: CN111395337A
Application number: CN202010374358.6A
Authority: CN
Inventors: 王林; 陶刚; 王军
Original assignee: Jiangsu Green River Environmental Technology Co ltd
Current assignee: Jiangsu Green River Environmental Technology Co ltd
Priority date: 2020-05-06
Filing date: 2020-05-06
Publication date: 2020-07-10
Also published as: WO2021223400A1

Abstract

A prefabricated combined assembled anti-floating tensile prestressed anchor rod piece comprises unbonded steel bars or main steel bars, a hollow pipe column for the prestressed anchor rod and a nut for locking an anchor; and (3) penetrating unbonded steel bars or main steel bars into the pipe column, taking the prefabricated hollow pipe column as a support, tensioning two ends of the steel bars, applying prestress, and locking the steel bars at two ends of the pipe column by nuts to form a prefabricated prestressed anchor rod piece. The main reinforcement steel bar is high-strength finish-rolled deformed steel bar; and an anti-corrosion grease layer is arranged on the surface of the main reinforcement steel bar, and a sleeve is arranged outside the anti-corrosion grease layer to form the pre-stressed unbonded steel bar.

Description

Prefabricated combined assembled anti-floating tensile prestressed anchor rod piece and construction method thereof

Technical Field

The invention relates to a novel prestressed anchor rod, in particular to an anti-floating tensile anchor rod applied by pre-tensioning or post-tensioning prestress and a construction method. The prepared anti-floating tensile reinforced bar anchor rod can be used for prefabricating a prestressed anchor rod assembly by a post-tensioning method and an application technology, various anchor heads such as a straight-through or an expansion head are combined together to form a post-tensioning prestressed anchor rod system, the anti-floating deformation and the elastic deformation of the rod body in a free section are overcome, and the anti-floating tensile reinforced bar anchor rod relates to an anchor rod system and a compression-resistant pile system for overcoming the prestress applied by an anti-floating straight-through or expansion head band.

Background

The technology of the straight-through or expanded head prestressed anchor rod is a novel underground engineering application technology, and accords with the spirit of energy conservation, emission reduction and green development advocated by the state. Compared with the common traditional process, the method is more economic and environment-friendly in the aspects of solving the problems of basement anti-floating, foundation pit supporting and the like; meanwhile, the method has great advantages in the aspects of cost, construction period, durability and the like. Along with the popularization of the expanding prestressed anchor rod technology, more and more projects adopt the expanding prestressed anchor rod technology to carry out basement anti-floating, foundation pit supporting and the like. Meanwhile, a large number of engineering practices show that the bearing tension of the prestressed anchor rod is far greater than that of a common anchor rod, and the deformation displacement of the common anchor rod is larger, so that the requirement on displacement control is higher than that of a traditional pile foundation, and how to better control the deformation of the anchor rod is an important direction for improving the expanded anchor rod technology. The known prestressed anchor rod deformation comprises elastic deformation of a free section of a rod body and creep deformation of a soil body of an anchoring section of an expanded head, corresponding products and construction methods are needed, and the prestressed anchor rod deformation construction method also relates to a pressure-bearing straight-through or variable-diameter reinforcement cage expanded body anchor rod prestress construction method.

CN201310321525.0 provides a prestressed drilling, anchoring and grouting anchor cable and a supporting method, wherein the prestressed drilling, anchoring and grouting anchor cable comprises a hollow grouting anchor cable with a sleeve head, a sleeve, a lock, a gasket and a tray; the front end of the sleeve is provided with a drill bit, and the sleeve is provided with an anchoring hole and a thread. The hollow grouting anchor cable drives the sleeve to drill, the hollow grouting anchor cable is pushed inwards through threads during reverse rotation, the metal nail at the front end of the sleeve head punctures the anchoring agent package inside the sleeve, the anchoring agent is discharged through the anchoring hole in the sleeve after being mixed, and the gap between the sleeve and the wall of the drilled hole is filled with the anchoring agent, so that the anchoring effect is achieved. The one-time drilling, anchoring and grouting support for the loose coal rocks is realized, and the problem that anchor cables are difficult to enter due to drill hole jamming and collapse of the loose coal rocks is solved.

CN201710363883 is a construction method for overcoming deformation of an anti-floating fixed-diameter anchor head or an expanded head anchor rod system, which is previously applied by the applicant, when a drill hole is drilled to a designed depth, high-pressure jet grouting construction or mechanical reaming construction can be carried out, a pull rod of an anchor rod and the fixed-diameter anchor head or the expanded head are put down, an expanding mechanism expands the expanded head to a designed size after the expanded head is in place, and then high-pressure grouting or pouring concrete forms a pile in the expanded section and the whole free section; the tie rod in the anchor rod adopts a twisted steel bar which can apply prestress; binding the spiral stirrups and the foundation slab steel bars on the substrate, and avoiding collision with prestressed steel bars in the binding process; and finally, the formwork is erected to pour the foundation concrete foundation slab.

The technique for prefabricating the prestressed anchor rod member by using the pretensioning method is as follows: the engineering practice shows; the displacement of the pressure-bearing type variable-diameter steel reinforcement cage expansion anchor rod consists of two parts of elastic deformation of a rod body and sliding (plastic deformation) of an expansion body section. The application of the pre-stressed anchor rod is also provided by the applicant: CN2017103638836 is a precast prestressed anchor rod member and a construction method thereof; CN2017103638836 is a method for overcoming deformation of an anti-floating fixed-diameter anchor head or an expanded head anchor rod system, but the prestressed anchor rod piece still has an improvement.

The enlarged head anchor rod technology is a novel underground engineering application technology, and accords with the spirit of energy conservation, emission reduction and green development advocated by the state. Compared with the common traditional process, the method is more economic and environment-friendly in the aspects of solving the problems of basement anti-floating, foundation pit supporting and the like; meanwhile, the method has great advantages in the aspects of construction period, durability and the like. Along with the popularization of the expanded anchor rod technology, more and more projects adopt the expanded anchor rod technology to carry out basement anti-floating, foundation pit supporting and the like. Meanwhile, a great deal of engineering practice shows that the bearing tension of the anchor rod is far greater than that of a common anchor rod, and the deformation displacement of the anchor rod is large, so that the displacement control is larger than that of a traditional pile foundation, and how to better control the deformation of the anchor rod is an important direction for improving the expanded anchor rod technology. Through a test anchor test, under the action of ultimate withdrawal resistance, the maximum deformation of the anchor rod is 81.6mm, the residual deformation is about 31.3mm, and the actual elastic deformation is 50.3 mm. It can be seen that the elastic deformation of the anchor rod accounts for more than 50% of the maximum deformation of the anchor rod.

The elastic deformation of the free section of the anchor rod body is controlled, and the elastic deformation of the rod body, namely the elastic deformation of the reinforcing steel bar, is mainly controlled by the sectional area of the reinforcing steel bar of the rod body, the elastic modulus of the reinforcing steel bar and the length of the rod body. Axial tension-compression deformation formula:

taking an anti-floating anchor rod of a basement of Nanjing as an example, the anchor rod has a total length of 13m (wherein the common section of the anchor rod is 10.0m long and 200mm in diameter, and the section of the expansion body is 750mm long and 3.0m long), and an anti-pulling characteristic value of 500 KN. The table for calculating the theoretical elastic displacement of the uplift anchor rod is as follows:

under extreme load conditions, the theoretical free deformation of the bolt is up to 51.75 mm.

Through a test anchor test, under the action of ultimate withdrawal resistance, the maximum deformation of the anchor rod is 81.6mm, the residual deformation is about 31.3mm, and the actual elastic deformation is 50.3 mm. Therefore, the elastic deformation of the anchor rod accounts for more than 50% of the maximum deformation of the anchor rod of the enlarged head.

For the deformation control of the enlarged head anti-floating anchor rod, the main method at the present stage is to apply prestress by a post-tensioning method to solve the elastic deformation of the free section of the anchor rod, and the concrete implementation steps are that after the main structure bottom plate is poured, a groove is formed in the bottom plate, the bottom plate is used as a fulcrum for applying the prestress, and after the prestress is applied, concrete at the groove is poured later to complete the locking of the anchor rod. The deformation control method has the main defects that prestress can be applied only after the prestress is applied and the design strength is reached after the prestress is applied simultaneously in the construction period of the base plate, so that grooves are required to be formed in the base plate of the main structure when the working stress is greatly delayed, the main structure is damaged in different degrees, the basement water resistance is adversely affected, the requirement on foundation pit precipitation is longer, and the relative cost is increased more. The method for controlling the deformation of the free section of the pressure-bearing straight-through or variable-diameter steel reinforcement cage expansion anchor rod is not solved.

The prestressed anchor rod assembly has the improvement of providing pre-tensioned or post-tensioned prestressed anti-floating tensile prestressed steel anchor rod member, mainly providing unbounded finish-rolled steel bars as main bars of the anchor rod, assembling and prefabricating the anti-floating tensile prestressed anchor rod member, wherein the member consists of prefabricated prestressed unbounded steel bars for the anti-floating tensile anchor rod, a hollow tubular column for the prefabricated prestressed anchor rod, a connecting and anchor locking nut. And penetrating the unbonded steel bar part into the pipe column, taking the prefabricated hollow pipe column as a support, tensioning two ends of the steel bar by a pretensioning method, applying prestress, and locking by using a nut to form the prefabricated prestressed anchor rod component.

Disclosure of Invention

The invention aims to provide a pretensioned or post-tensioned prestressing anti-floating tensile anchor rod reinforcing steel bar, an anchor rod and a construction method. The prepared anti-floating tensile reinforced bar anchor rod can be used for prefabricating a prestressed anchor rod assembly by a pretensioning method and an application technology, various anchor heads such as a straight-through or an expanding head are combined together to form a prestressed anchor rod system, the anti-floating deformation and the elastic deformation of a rod body in a free section are overcome, the prestress is applied after the rod body is prepared by a new method, and a finished product of the prestressed anchor rod is obtained for application, so that the purpose of controlling the deformation amount in the engineering practice of the pressure-bearing type straight-through or variable-diameter reinforcement cage expanding prestressed anchor rod is achieved, the industrial production can be well solved, the standard problems of tension cracking, corrosion resistance and elastic deformation are solved, and particularly the effects of saving the construction time, saving the cost and improving the engineering quality and efficiency are achieved. Meanwhile, a construction method for reducing the soil body creep deformation of the prestressed anchor rod in the working state is also provided.

The technical scheme of the invention is that the prefabricated combined assembled anti-floating tensile prestressed anchor rod piece comprises unbonded steel bars or main steel bars, a hollow pipe column for the prestressed anchor rod and a nut for locking the anchor; and (3) penetrating unbonded steel bars or main steel bars into the pipe column, taking the prefabricated hollow pipe column as a support, tensioning two ends of the steel bars, applying prestress, and locking the steel bars at two ends of the pipe column by nuts to form a prefabricated prestressed anchor rod piece.

The anti-floating tensile anchor rod is made of prefabricated prestressed unbonded steel bars, and the main steel bar is high-strength finish-rolled deformed steel bar; and an anti-corrosion grease layer is arranged on the surface of the main reinforcement steel bar, and a sleeve is arranged outside the anti-corrosion grease layer to form the pre-stressed unbonded steel bar. The main reinforcing steel bar is a main reinforcing steel bar structure which connects the segmented main reinforcing steel bar through the connecting nut, and the segmented main reinforcing steel bar can be connected with the lengthened main reinforcing steel bar structure through the connecting nut. The quantity of main muscle reinforcing bar is one or one to 6 parallel reinforcing bars, at the central evenly distributed of prestressed anchorage pole, and main muscle reinforcing bar chooses screw thread round steel, steel pipe, steel strand wires or shaped steel for use, and the steel pipe is equipped with the silking with shaped steel both ends, and the sleeve pipe is the sleeve pipe of metal forming, plastics material.

The hollow pipe column for the prefabricated prestressed anchor rod comprises a pipe column which is prefabricated by concrete and provided with a steel bar framework, wherein the pipe column can contain unbonded steel bars for the anchor rod, the general inner diameter is 3-7 cm, the outer diameter is 10-30 cm, the size can be set according to engineering requirements, the framework is arranged or not arranged in the pipe column prefabricated by the concrete, a reinforcement material is selected by the framework, selectable reinforcement materials comprise but are not limited to a plurality of vertical steel bars, stirrups, steel sleeves, steel wire mesh cages of the steel bar cages, bearing plates, anchoring plates, bearing flanges and the like, and the reinforcement materials are wrapped by one of concrete or cement mortar, cement paste or other curable materials and are solidified to form the pipe column.

The hollow pipe column for the prefabricated prestressed anchor rod applies prestress to the vertical reinforcing steel bar of the reinforcing steel material, the steel sleeve, the reinforcing steel bar cage and the steel wire mesh cage, then the hollow pipe column is wrapped with one of concrete or cement mortar, cement paste or other curable materials and is solidified by condensation, and the hollow pipe column can also be filled into a solid state, so that the prefabricated prestressed pipe column is formed, and the hollow pipe column can also be used as an independent commodity anchor rod assembly of the prefabricated prestressed pipe column. The invention is composed of prefabricated prestressed non-binding steel bar for anti-floating tensile anchor rod, pipe column for prefabricated prestressed anchor rod, connection and anchor locking nut, besides, it can also be used as prefabricated prestressed non-binding steel bar independent commodity, and used in various anchor rod application schemes using pre-tensioning method and post-tensioning method to solve the problem of prestress; the steel bars in the hollow pipe column for the pre-stressed anchor rod can be prefabricated, and grease and sleeves can be omitted according to design requirements.

The connecting and anchor locking nut can be external or embedded in a pipe column to be integrated with the pipe column for the prefabricated prestressed anchor, and two or more than two prefabricated prestressed anchor rod pieces are connected by adopting a nut connector or other methods to achieve the required length.

The pre-tensioned or post-tensioned prestressed anti-floating tensile anchor rod steel bar comprises a main steel bar (comprising a main steel bar or a main steel bar connecting structure which connects the main steel bar through a connecting nut) as a basic force-bearing structure, wherein the main steel bar is a finish-rolled non-bonded steel bar, the surface of the main steel bar is provided with an anti-corrosive grease layer, and the outer of the anti-corrosive grease layer is provided with a plastic film sleeve; coating the anticorrosive grease layer by a anticorrosive grease layer coating device, coating a polyethylene or polypropylene plastic film on the anticorrosive grease layer without bonding ribs by a plastic extruder, and forming a plastic sleeve (pipe) by a cooling cylinder mold; the plastic sleeve is wrapped by concrete or cement mortar, cement paste or other curable materials and is solidified; applying prestress on the main reinforcement steel bars, applying prestress after the solidification is finished and the required strength is reached, or prefabricating a finished product hollow pipe column with high strength to form a prestress anchor rod piece; and locking the main reinforcing steel bars by nuts, and applying prestress to the tensioned reinforcing steel bars to form the prefabricated prestressed anchor rod assembly. The end part of the main reinforcing steel bar can be provided with a reinforcing cage or a diameter-enlarged (diameter-variable) reinforcing cage; wrapping one of concrete or cement mortar, cement paste or other curable materials, and solidifying; according to the design requirement of prestress application, the main reinforcement is a steel bar, and a steel bar reinforcement material is configured, wherein the reinforcement material comprises a steel bar, a steel bar cage, a stirrup, a steel sleeve, a steel wire mesh cage, a bearing plate, a bearing flange nut, a connecting nut and the like; the main reinforcing steel bars and the reinforcing steel bar material are solidified together to form the anchor rod piece. The main reinforcing steel bar of the prestress anti-floating tensile reinforcing steel bar anchor rod applied later can fully reflect the anti-floating tensile stress of the reinforcing steel bar.

The non-adhesive pre-tensioned or post-tensioned prestressed anti-floating tensile steel bar anchor rod is formed, and the anti-corrosive grease layer is anti-corrosive grease or anti-corrosive asphalt, polymer or other anti-corrosive materials.

The front end of the main reinforcing steel bar of the anchor rod assembly is provided with a device which is connected or grafted with a variable-diameter reinforcing steel bar cage, a fixed-diameter reinforcing steel bar cage, a bag, an anchor backing plate or other anchor heads to form a prefabricated prestressed anchor rod system.

The combined assembly type anchor rod component forms an engineering part with compression resistance and tensile resistance (mainly tensile resistance and better effect) in practical application. The extension continuous type anchor rod is a rod piece which can be continuously formed into an extension continuous type anchor rod and finally becomes an assembly.

The prestressed fixing of the pretensioned prestressed anti-floating tensile steel bar anchor rod generally adopts two modes, one mode is that concrete is poured on the prestressed steel bar while the prestress is exerted, and the prestressed steel bar anchor rod is formed after the concrete is solidified; the concrete is tightly bonded with the anchor rod, namely a bonded anchor rod is arranged; secondly, the invention can adopt the prefabricated pipe column to form a prestressed structure of the hollow anchor rod, is convenient for factory production, has controllable weight and low transportation cost, and the application quality and standard of the prestressed force are easier to control and master in the factory. When the anchor rod with no binding steel bars or the finished tubular column (which can be called as a hollow anchor rod column) is used, the anchor rod steel bars penetrate through the finished tubular column, when the finished tubular column is used, a bearing plate (also called as an anchor backing plate and the like) with a hole in the center and larger than the inner diameter of the tubular column is arranged at two ends of the finished tubular column, when the anchor rod exposed out of the surface of the bearing plate is stressed, the steel bar end is fixed on the bearing plate or the steel bar end is welded and fixed on the bearing plate by a nut, the steel bars can be single finish-rolled anchor rod steel bars or a plurality of anchor rod steel bars, and when the anchor rod steel bars are a plurality of anchor rod steel bars, a bearing plate is; generally, the post-application process needs to be carried out in the construction process, the post-application process is troublesome in engineering, equipment needs to be pulled to the site, the cost is high, particularly, the quality of applied prestress and whether the rated requirement can be met are difficult to guarantee, and the invention provides an anti-floating tensile combined anchor rod component (comprising an adhesive anchor rod and an unbonded anchor rod) and a corresponding construction method. When the anchor rod or the finished pipe column is made without the bonding reinforcing steel bars, the bonding reinforcing steel bars can be used as the reinforcing steel bars of the anchor rod in the finished pipe column; the concrete and the reinforcing steel bars in the anchor rod are not bonded, the reinforcing steel bars in the anchor rod can stretch out and draw back or slide in the pipe column or the plastic film sleeve, a post-tensioning method, namely, prestress is applied on a construction site, and the nuts are fastened while the reinforcing steel bars are prestressed.

The non-binding steel bar anchor rod can be matched with the hollow anchor rod pipe column, can be matched with pre-tensioning or post-tensioning prestressed anti-floating tensile non-binding anchor rod steel bars, and the pre-tensioning prestressed anti-floating tensile steel bar anchor rod can be connected to a designed rated length or can be connected with a steel bar cage expansion head with a variable diameter, so that a practical engineering system is formed.

The main muscle reinforcing bar (including main muscle reinforcing bar or with main muscle reinforcing bar through coupling nut's main muscle reinforcing bar connection structure) is used as the structure of basic load to the main atress spare of stock, and the main muscle reinforcing bar can adopt ordinary reinforcing bar, include finish rolling reinforcing bar or add anticorrosive processing in surface again, and the anchor stock reinforcing bar of unbonded still can have following structure: the surface of the main reinforcement steel bar is provided with an anti-corrosive grease layer, and a plastic film sleeve is arranged outside the anti-corrosive grease layer; coating the anticorrosive grease layer by a anticorrosive grease layer coating device, coating a polyethylene or polypropylene plastic film on the anticorrosive grease layer without bonding ribs by a plastic extruder, and forming a plastic sleeve (pipe) by a cooling cylinder mold; the plastic sleeve is wrapped by concrete or cement mortar, cement paste or other curable materials and is solidified; applying prestress on the main reinforcing steel bars after prestress (applying prestress after fixing is finished) to form a prestress anchor rod assembly; and locking the main reinforcing steel bars by nuts, and applying prestress to the tensioned reinforcing steel bars to form the prestressed anchor rod assembly.

When the plastic film sleeve reinforcing steel bar, especially the post-tensioned prestressing anti-floating tensile reinforcing steel bar anchor rod is applied, the prestressed main reinforcing steel bar actually forms a free section reinforcing steel bar, and has the function of applying stress.

An application method of a pre-tensioned or post-tensioned prestressed anti-floating tensile steel bar anchor rod. The method comprises the following steps: drilling to a designed depth, carrying out high-pressure jet grouting construction or mechanical reaming construction, placing an anchor rod steel bar piece to be connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other anchor heads after forming a hole, releasing a restraint mechanism to expand the variable-diameter steel bar cage to a designed size after an expansion head with the variable-diameter steel bar cage is in place, and then pouring grout or pouring concrete into the expansion section of the variable-diameter steel bar cage to form the anchor head; the top of the anchor rod steel bar is fixed by a flange nut sleeve embedded in and sleeved with the steel bar, or can be fixed by an anchor plate and a nut and connected with a steel bar framework system of the foundation slab, and the post-tensioning method applied stress is fixed by the flange nut sleeve when the post-tensioning method is applied stress; grouting or pouring concrete into the gap between the steel bar and the hole to complete the prestressed anchor rod piece; finally, installing a formwork and pouring a concrete foundation slab fixing anchor plate; the use of a pre-stressed anchor rod assembly does not require post-stressing. When the anchor rod assembly is connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other (expanded) anchor heads, steel bars with the length suitable for the variable-diameter steel bar cage, the fixed-diameter steel bar cage, the bag or other anchor heads are reserved at the lower end of the anchor rod assembly, the bottom of the anchor head is connected with an anchor backing plate (the steel bars are welded or main steel bars are connected through connecting nuts), the proper length of the steel bars is reserved, and the proper length of the steel bars is connected with the top of the finished anchor head through the connecting nuts; by improving the rod piece and the anchor head, the anchor rod assembly and the variable-diameter reinforcement cage, the fixed-diameter reinforcement cage, the bag or other anchor heads form an organic whole. The prepared anti-floating tensile reinforced bar anchor rod can be used for prefabricating a prestressed anchor rod assembly by a post-tensioning method and an application technology, various anchor heads such as a straight-through or an expanding head are combined together to form a post-tensioning prestressed anchor rod system, the anti-floating deformation and the elastic deformation of a rod body in a free section are overcome, the prestress is applied after the rod body is prepared by a new method, and a finished product of a prestressed anchor rod is obtained for application, so that the purpose of controlling the deformation amount in the engineering practice of the pressure-bearing straight-through or variable-diameter reinforcement cage expanding prestressed anchor rod is achieved, and particularly the effects of saving the construction time, saving the cost and improving the engineering quality and efficiency are achieved. Meanwhile, a construction method for reducing the soil body creep deformation of the prestressed anchor rod in the working state is also provided.

The end part of the main reinforcing steel bar is provided with a reinforcing cage or a diameter-enlarged (diameter-variable) reinforcing cage; wrapping one of concrete or cement mortar, cement paste or other curable materials, and solidifying; according to the design requirement of prestress application, the main reinforcement is a steel reinforcement, and a steel reinforcement material is configured, wherein the reinforcement material comprises a steel reinforcement cage, a stirrup, a steel sleeve, a steel wire mesh cage, a pressure bearing plate and a pressure bearing flange nut; the main reinforcing steel bars and the reinforcing steel bar material are solidified together to form the anchor rod assembly. The main reinforcing steel bar of the prestress anti-floating tensile reinforcing steel bar anchor rod applied later can fully reflect the anti-floating tensile stress of the reinforcing steel bar. The prefabricated combined assembled anti-floating tensile prestressed anchor rod piece, the tubular column for the prefabricated prestressed anchor rod, the prefabricated prestressed unbonded steel bar and the lengthening form thereof can be wrapped, condensed and cured with concrete or cement mortar, cement paste or other curable materials to independently form the application of a prestressed anchor rod body (non-expanded head anchor rod). Further, the anchor head can also be connected with a reinforcement cage, an enlarged diameter (variable diameter) reinforcement cage, a variable diameter reinforcement cage, a fixed diameter reinforcement cage, a bag, a pressure-bearing anchor plate or other anchor head bearing bodies which are arranged at the enlarged bottom end part, under the condition of applying stress, concrete or cement mortar, cement paste or other curable materials are poured to wrap the reinforcement cage, and are solidified together to form the application of the prestressed anchor rod pile with the enlarged head

The non-adhesive pre-tensioned or post-tensioned prestressed anti-floating tensile steel bar anchor rod is formed, and the anti-corrosion grease layer is made of anti-corrosion grease, anti-corrosion asphalt, polymer materials or other anti-corrosion materials.

The front end of the anchor rod component main reinforcing steel bar is provided with a device which is connected or grafted with a variable-diameter reinforcing steel bar cage, a fixed-diameter reinforcing steel bar cage, a bag or other anchor heads to form a prefabricated prestressed anchor rod system.

The number of the main reinforcing steel bars of the anchor rod assembly, which is one or more than one reinforcing steel bars in the anchor rod assembly applying post-tensioning prestress is generally not more than 10 (otherwise, the reinforcing steel bars become concrete piles), and the specification, the performance, the strength and the diameter of the reinforcing steel bars can be specifically determined according to the design requirement; the length, the shape and the area of the cross section of the prestressed anchor rod assembly are set according to specific engineering technical requirements; when the length of the rod piece required by engineering is overlong, two or more than two steel bar rod pieces can be connected by adopting a nut connector or other modes so as to achieve the required length; the reinforcing steel bar nut connector can also be embedded in the anchor rod in advance, the reinforcing steel bar can be round steel, steel pipe, steel strand and other section steel, and the two ends of the section steel can also be provided with threads.

The anchor rod assembly and the variable-diameter reinforcement cage have solid geometrical shapes including but not limited to: cubes, polyhedrons, regular polyhedrons, tetrahedrons, cuboids, cylinders, round tables, prisms, prismatic tables, cones, pyramids, bamboo joints, strings and convexo-concave shapes; the shape of the planar cross-section includes, but is not limited to: square, rectangle, triangle, quadrilateral, rhombus, trapezoid, polygon, circle, ellipse, ring, sector and bow; the anchor assembly may be solid or hollow in cross-section.

The anchor rod piece, the tubular column for the prefabricated prestressed anchor rod, the prefabricated prestressed unbonded steel bar for the anti-floating tensile anchor rod and the main bar and the reinforcing bar in the lengthened form can be selected from materials including but not limited to steel, steel stranded wires, glass fibers, resin, glass fiber reinforced resin, aramid fibers, carbon fibers, graphene, carbon element-related materials and composite materials thereof, polymers, high polymer materials, nano materials, metal materials and non-metal materials.

The invention is applicable to the fields including but not limited to the functional application of anti-floating and tensile strength, and the specific application includes building, road, mining, tunnel and bridge, foundation pit and mountain slope protection, and geological disaster treatment; also used in the fields of pressure-resistant engineering and the like. The prefabricated prestressed anchor rod body can be used as a prefabricated prestressed compression-resistant pile according to the requirements of engineering design purposes.

The pre-tensioning or post-tensioning method adopts a prefabricated prestressed anchor rod body and the application method thereof comprises the following steps: the method is used for overcoming the deformation of an anti-floating fixed-diameter anchor head or an expanded head prestressed anchor rod, drilling to a designed depth, carrying out high-pressure jet grouting construction or mechanical hole expanding construction, placing an anchor rod steel bar piece to be connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other anchor heads after hole forming, releasing a constraint mechanism to expand the variable-diameter steel bar cage to a designed size after the expanded head with the variable-diameter steel bar cage is in place, and then grouting or pouring concrete to pour the variable-diameter steel bar cage expanded section into the anchor head; the top of the anchor rod steel bar is fixed by a flange nut (kit) embedded and sleeved on the steel bar (pull rod), or can be fixed by a nut through an anchor plate and connected with a steel bar framework system of the foundation slab, and the top of the anchor rod steel bar is fixed by the flange nut (kit) when a post-tensioning method applies stress (post-stressing); grouting or pouring concrete into the gap between the steel bar and the hole to complete the prestressed anchor rod piece; and finally, installing a formwork and pouring a concrete foundation slab fixing anchor plate. And when the pre-fabricated prestressed anchor rod component is adopted, post-stressing is not needed. The pre-tensioning method does not require stress application and has been prepared as a pre-stressed unit.

When the anchor rod assembly is connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other anchor heads, steel bars with the length suitable for the variable-diameter steel bar cage, the fixed-diameter steel bar cage, the bag or other anchor heads are reserved at the lower end of the anchor rod assembly, the bottom of the anchor head is connected with an anchor backing plate (the steel bars are welded or main steel bars are connected through connecting nuts), and the proper length of the steel bars can be reserved and connected with the top of the finished anchor head through the connecting nuts; by improving the rod piece and the anchor head, the anchor rod assembly and the variable-diameter reinforcement cage, the fixed-diameter reinforcement cage, the bag or other anchor heads form an organic whole.

When the pre-stressed anchor rod prepared by a pre-tensioning method is adopted, a pre-stressed anchor rod component and a variable-diameter reinforcement cage are placed, a plurality of pre-stressed anchor rod component units are adopted, and two to a plurality of anchor rod units with different fixed sizes are selected to be connected into an anchor rod component with the required length; the lowest anchor rod in the connection method and a plurality of anchor rods with different fixed sizes at the upper end of the anchor head can be conveniently connected into an anchor rod piece with the required length; the flange nut (complete set) is used for fixing without applying stress (post stress, tensile stress); and grouting or pouring concrete into the anchor head and the gaps at the joint of the steel bars and the unit and the periphery of the unit in the section of the variable-diameter steel bar cage expander.

When the anchor rod assembly is connected with a variable-diameter reinforcement cage, a fixed-diameter reinforcement cage, a bag or other anchor heads, the reinforcement cage of the post-tensioning precast prestressed anchor rod assembly is characterized in that reinforcement bars with the length suitable for the variable-diameter reinforcement cage, the fixed-diameter reinforcement cage, the bag or other anchor heads are reserved at the lower end of the anchor rod assembly, the bottom of the anchor head is connected with an anchor backing plate, and the proper length of the reinforcement bars can also be reserved, and the lower end of the reinforcement bar of the anchor rod assembly is connected with the top of a finished anchor head through a connecting nut; or the anchor rod component and the variable-diameter reinforcement cage, the fixed-diameter reinforcement cage, the bag or other anchor heads are integrated into an organic whole by improving the anchor rod component and the anchor heads. The applied stress is generally only applied to the bolt of the present invention.

The invention relates to a concrete prefabricated pipe column, which is characterized in that a steel reinforcement framework of the concrete prefabricated pipe column is provided with a connecting piece at the bottom end, and the connecting piece can be connected with a steel reinforcement cage at the lower end in a fixing mode, particularly in a screwing mode or a welding mode and the like (particularly, the applicant firstly provides a variable-diameter steel reinforcement cage, particularly, a main reinforcement is connected, the center of the variable-diameter steel reinforcement cage needs the main reinforcement, and the main reinforcement of the variable-diameter steel reinforcement cage does not need prestress, so that a concrete foundation with the diameter larger than that of the concrete prefabricated pipe column is formed, the foundation is grouted through a grouting pipe, and the concrete prefabricated pipe column has larger tensile and pressure-resisting capabilities).

The invention is matched with a pre-tensioning or post-tensioning prestressed anti-floating tensile steel bar anchor rod, in particular to a pre-tensioning prestressed anti-floating tensile steel bar anchor rod and a system. The anchor rod is with main muscle reinforcing bar (including main muscle reinforcing bar or with main muscle reinforcing bar through coupling nut's main muscle reinforcing bar connection structure) as the structure of basic load, and main muscle reinforcing bar can adopt ordinary reinforcing bar, include finish rolling reinforcing bar or add anticorrosive processing in surface again, and main muscle reinforcing bar can also have following structure: the surface of the main reinforcement steel bar is provided with an anti-corrosive grease layer, and a plastic film sleeve is arranged outside the anti-corrosive grease layer; coating the anticorrosive grease layer by a anticorrosive grease layer coating device, coating a polyethylene or polypropylene plastic film layer on the anticorrosive grease layer without bonding ribs by a plastic extruder, and forming a plastic sleeve (pipe) by a cooling cylinder mold; the plastic sleeve is wrapped by concrete or cement mortar, cement paste or other curable materials and is solidified; after the prestress is applied to the main reinforcing steel bars (after the fixation is finished, the prestress is applied), and after the prestress is applied to the tensioning reinforcing steel bars, the main reinforcing steel bars are locked by nuts to form the prestressed anchor rod piece.

When the plastic film sleeve reinforcing steel bar, especially the post-tensioned prestressing anti-floating tensile reinforcing steel bar anchor rod is applied, the prestressed main reinforcing steel bar actually forms a free section reinforcing steel bar, and the sleeve can be made of various materials such as metal, PP, PE, PVC, plastics and the like.

The invention discloses a pretensioned or post-tensioned prestressed anti-floating tensile steel bar anchor rod and a construction method. The prepared anti-floating tensile reinforced bar anchor rod, in particular to an anchor rod piece capable of prefabricating prestress by a post-tensioning method and an application technology, utilizes various anchor heads such as a straight-through or an expanding head to be combined together to form a post-tensioning prestress anchor rod system, overcomes the anti-floating deformation and the elastic deformation of the rod body in a free section, applies prestress after preparing the rod piece by a new method and obtains a finished product of a prestress anchor rod to be applied, thereby not only achieving the purpose of controlling the deformation amount in the engineering practice of the pressure-bearing type straight-through or variable-diameter reinforcement cage expanding prestress anchor rod, but also particularly achieving the effects of saving the construction time, saving the cost and improving the engineering quality and efficiency. Meanwhile, a construction method for reducing the soil body creep deformation of the prestressed anchor rod in the working state is also provided.

The construction method is the same as that of post-tensioning method, but the prestressed tendons are not in direct contact with concrete and are in a non-adhesive state. The unbonded prestressed tendon is a special prestressed tendon with an anticorrosive isolation layer and an outer sheath. The unbonded prestressed tendons have higher requirements on the safety reliability and durability of the anchorage device; because the unbonded prestressed tendon and the concrete can slide relatively in the longitudinal direction, the tensile capacity of the prestressed tendon can not be fully exerted, and a certain amount of bonding tendon in the body is required to be configured to limit the crack of the concrete.

Has the advantages that: the construction method of the unbonded prestressed reinforcement is the same as that of the post-tensioning method, but the prestressed reinforcement is not in direct contact with concrete, and the prestressed reinforcement is in an unbonded state. The unbonded prestressed tendon is a special prestressed tendon with an anticorrosive isolation layer and an outer sheath. The unbonded prestressed reinforcement has higher requirements on the safety reliability and the durability of the anchorage device; because the unbonded prestressed tendon and the concrete can slide longitudinally, the tensile strength of the prestressed tendon can be fully exerted, and a certain bonding tendon is preferably arranged in the concrete rod body of the anchor rod member to limit the crack of the concrete.

The unbonded prestressed tendon has the characteristics that: 1. simple structure and light dead weight. The prestressed tendon pore canal does not need to be reserved, the prestressed tendon pore canal is suitable for components with complex structures and curved tendon arrangement, and the components have reduced sizes and self weights. 2. The construction is simple and convenient, and the equipment requirement is low. Complex processes such as pipeline reservation, grouting penetration and the like are not needed, and a tensioning support can be omitted by replacing a pre-tensioning method in the manufacturing of the medium-small span bridge, so that the construction process is simplified, and the construction progress is accelerated. 3. The prestress loss is small and the tension can be compensated. An anti-corrosion grease layer is arranged between the prestressed tendons and the outer sheath, so that the tension friction loss is small, and the prestressed tendons can be tensioned in a supplementing way during the service life. 4. The corrosion resistance is strong. The unbonded prestressed tendon coated with anticorrosive grease, PE jacket and other sheaths has double anticorrosive capacity. The danger that the prestressed tendon is corroded and the like due to the fact that grouting is not compact can be avoided. 5. The service performance is good. By adopting the mixed reinforcement of the unbonded prestressed reinforcement and the common steel bar, the ultimate bearing capacity can be met, and the concentrated cracks can be avoided, so that the prestressed concrete has similar mechanical properties to the prestressed concrete with the bonded part. 6. The fatigue resistance is good. The unbonded prestressed tendon and the concrete can longitudinally and relatively slide, the stress amplitude is small in the use stage, and the fatigue problem is avoided. 7. The shock resistance is good. When earthquake load causes large displacement, the sliding unbonded prestressed tendon is generally always in a tensioned state, the stress change amplitude is small and is kept in an elastic working stage, and the common steel bar enables structural energy to be dissipated to ensure that the construction method of the unbonded prestressed tendon is the same as that of a post-tensioning method, but the prestressed tendon is not directly contacted with concrete and is in an unbonded state. The unbonded prestressed tendon is a special prestressed tendon with an anticorrosive isolation layer and an outer sheath.

The invention can be applied by a pre-tensioning method completely, and even if the pre-tensioned pre-stressed anchor rod is adopted by the post-tensioning method, the pre-stressed anchor rod has no large displacement on the whole although the steel bar has deformation. Prestress is applied and poured during construction, and the prestress is applied after field operation so that the tension effect of the anchor rod is optimal, but the requirement on field construction control is higher. The invention makes the bearing capacity reach the applied prestress value required by design through the application of the post-added prestressed anchor, the deformation of the free section of the prestressed anchor can be continuously adjusted, and meanwhile, the scheme is simpler in construction and basically has no influence on the construction of the foundation. Has positive effect on improving the engineering quality and the safety of the technology.

The invention particularly combines the anchor rod with the lower end, the reducing steel bar cage and the grouting body or the concrete anchor head to obtain strong foundation support in mechanics, has reliable tensile resistance transmission, and can improve the tensile resistance of the anchor rod by more than 2 times. The main reinforcing steel bar welding or the special nut connector of stock owner reinforcing steel bar lower extreme reducing steel bar cage connect, can guarantee the reliability of connecting, and the main reinforcing steel bar of reducing steel bar cage can need not to adopt the high-quality reinforcing steel bar of enduring the high stress.

Drawings

FIG. 1 is a schematic diagram of the preparation of a prestressed anchor according to the present invention;

FIG. 2 is a schematic view of a prestressed anchor according to the present invention;

FIG. 3 is a schematic view of a concrete pad 2 poured over the base 1 of the present invention; namely pouring a concrete cushion;

FIG. 4 is a schematic diagram of the anchoring sections at the upper end and the lower end of the expanding pre-stressed anchor rod of the variable-diameter steel reinforcement cage.

FIG. 5 is a schematic view of the lower end anchor structure of the steel reinforcement cage enlarged head of the pre-stressed anchor rod of the variable diameter steel reinforcement cage enlarged body of FIG. 4;

FIG. 6 is a schematic view of the reinforcement structure of the unbonded anchor rod;

FIG. 7 is a schematic view showing a connection structure of anchor rods for a hollow tubular column;

FIG. 8 is a schematic view showing a pre-tensioning unit and connection structure of a reinforcing bar of an anchor rod for a hollow pipe column;

FIG. 9 is a schematic view of the connection structure of the lower end of the anchor member according to the present invention;

FIG. 10 is a schematic view of a second connection at the lower end of the anchor member in accordance with the present invention;

FIG. 11 is a schematic view of a third connection configuration of the lower end of the anchor members of the present invention;

fig. 12 is a schematic view of a fourth connection configuration for the lower end of the anchor members of the present invention.

Fig. 13 is a schematic view of the construction of the non-bonded steel bar (or ordinary steel bar) stress anchor rod of the present invention;

fig. 14 is a schematic view of the construction of a non-bonded steel bar (or ordinary steel bar) stress anchor rod of the present invention; comparing to fig. 13, this figure shows two stress bolts with an internal coupling nut connected to different lengths;

FIG. 15 is a schematic view of a construction of a stress anchor rod formed by wrapping reinforcing bars with concrete according to the present invention; two stress anchor rods are connected into anchor rods with different lengths, wherein the two stress anchor rods are provided with embedded connecting nuts;

FIG. 16 is a schematic view of a construction of a stress anchor rod formed by wrapping reinforcing bars with concrete according to the present invention; two stress anchor rods are connected into anchor rods with different lengths, wherein the two stress anchor rods are provided with exposed connecting nuts 13;

FIG. 17 is a schematic view of a construction of the reinforced concrete with the steel skeletons 3-7 and the bearing plates (with steel bar through holes) distributed therein to form a stress anchor rod according to the present invention;

FIG. 18 is a schematic view of the construction of the reinforced concrete with the steel reinforcement frames 3-7 and the bearing plate (with steel reinforcement through holes) distributed therein to form the stress anchor rods according to the present invention; in comparison with fig. 17, an in-line coupling nut is provided.

FIG. 19 is a schematic view of a structure of the reinforced concrete with a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein to form a stress anchor rod according to the present invention;

FIG. 20 is a schematic view of a structure of the reinforced concrete with a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein to form a stress anchor rod according to the present invention; compared with fig. 20, 2-3 anchor rods are provided.

FIG. 21 is a schematic view of a structure of the reinforced concrete with a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein to form a stress anchor rod according to the present invention;

FIG. 22 is a schematic view of a structure of the reinforced concrete with a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein to form a stress anchor rod according to the present invention; but in the figure, the multi-root type anchor rod reinforcing steel bars 3-1-1 can be exposed at the end parts;

FIG. 23 is a schematic view of the construction of the anchor rod of the present invention in which the reinforced concrete has a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein; but the unstressed nut is fixed, and the other end is provided with a connecting nut which can be embedded.

Fig. 24 is a schematic view of the construction of a unbonded anchor rod of the invention.

Detailed Description

As shown, the parts in the figures are exemplified: the steel bar fixing device comprises a substrate 1, a concrete cushion layer 2, a poured anchor rod or anchor rod piece 3, a main bar or finish rolling coarse steel bar outer layer pipe column 3-2 prepared by pouring concrete or mortar, a fixing plate or bearing plate 3-4, a nut 3-3 applying prestress, an anti-corrosion grease layer 3-6, a plastic film sleeve 3-5, a limiting stopper 11 and a flange nut assembly 16-1, wherein the flange nut assembly 16-1 is used for fixing the anchor rod steel bar (the main bar or the finish rolling coarse steel bar) 3-1 on a bottom plate, and when stress is applied, the flange nut assembly 16-1 is used for fixing the main bar or the finish rolling coarse steel bar prestress after stress is applied. The water stop rubber strip 4, the flange nut 16, the concrete bottom plate 8, the concrete bottom plate steel bar 8-1, the bottom plate cushion layer 8-2 and the steel reinforcement cage 10 can be in a straight-through type or expanded head structure, and the diameter of the steel reinforcement cage can be changed in the drawing. Grout 12, nut connector 13, guide cap 14, enlarged head 15. The concrete body 12-1 and the reinforcement cage 10-1 with other structures are arranged in the bag 17; 3-8 middle shaft parts are poured with concrete, and 3-1-1 refers to a plurality of anchor rod reinforcing steel bars, generally not more than 5.

The embodiment of the invention comprises a prefabricated anti-corrosion steel bar rod piece for unbonded post-tensioning prestress of an anti-floating tensile anchor rod, a combined assembly type anti-floating tensile anchor rod component (comprising bonding and unbonded) prefabricated by a pre-tensioning method and a construction method thereof.

The prefabricated tubular column of concrete can with the tubular column swing joint of lower extreme: the steel reinforcement framework of the concrete prefabricated pipe column is a connecting piece at the bottom end and can be connected with the pipe column at the lower end in a fixing mode, particularly in a screwing mode or a welding mode and the like.

As shown in fig. 1, the structural schematic diagram of the prestressed anti-floating tensile reinforcement anchor rod includes a main reinforcement (a reinforcement rod, especially a precision cast reinforcement, a main reinforcement connection structure that passes through a connection nut for the precision cast reinforcement) as a basic force-bearing structure, an anti-corrosive grease layer is arranged on the surface of the main reinforcement, and a plastic film sleeve is arranged outside the anti-corrosive grease layer; coating the anticorrosive grease layer by an anticorrosive grease layer coating device, coating a polyethylene or polypropylene plastic film on the anticorrosive grease layer non-adhesive steel bars by a plastic extruder, and forming a plastic sleeve (pipe) by a cooling cylinder die; the plastic sleeve is wrapped by concrete or cement mortar, cement paste or other curable materials and is solidified; applying prestress on the main reinforcing steel bars to form a prefabricated prestressed anchor rod assembly; or the main reinforcing steel bar is penetrated into the steel pipe, two sections of the reinforcing steel bar are stretched, after prestress is applied, the steel pipe is used as a support, and the support is locked by a nut to form the prefabricated prestressed anchor rod component.

The prestressed anchor rod piece is prefabricated, the anchor rod reinforcing steel bar 3-1 is prestressed and then wrapped by concrete or mortar 3-2, and after the concrete or mortar is solidified to reach the design strength, the reinforced concrete is manufactured into the prestressed anchor rod piece 3. The reinforcement in the prestressed anchor rod assembly may be selected from, but is not limited to, a reinforcement cage, a stirrup, a steel sleeve, a wire mesh cage, a bearing plate (anchor plate), a bearing flange nut, or other reinforcement materials. Not shown in the figure. Wherein in FIG. 1: 3-4 parts of a fixing plate or a bearing plate (an anchor backing plate) for applying prestress, 3-3 parts of a nut, 3-1 parts of reinforcing steel bars, 3 parts of an anchor rod, 3-2 parts of reinforcing steel bars of a prestress anchor rod and concrete or mortar (the structure can be an independent sleeve structure or a structure similar to the sleeve structure, and can also be a structure which is tightly poured with the reinforcing steel bars of the anchor rod for applying stress). In order to apply stress, the structure of the independent sleeve needs to have better pressure resistance, the sleeve is particularly a steel bar framework, and the front end of the prestressed steel anchor rod is fixed with a diameter-variable steel bar cage and the like by using standard-size cement concrete and standard-size cement concrete; the prestressed anchor rod component can be applied when the diameter of the prestressed anchor rod component is smaller than the diameter of the drilled hole.

The nut is a fixed nut and is used for fixing the steel bar threaded nut applying prestress.

In the basic structure of the concrete or mortar (i.e. pipe column) 3-2 and the steel bar 3-1 of the outer layer of the main bar or the finish rolling coarse steel bar prepared by pouring the concrete or the mortar in the figure 2.

FIG. 3 is a schematic view of a concrete pad 2 poured on the foundation 1 of the present invention; in FIG. 3, a substrate 1, a concrete cushion 2 and a poured concrete cushion are shown; the anchor rod assembly 3, the water stop rubber strip 4 and the water stop rubber strip 4 need to be embedded into the center of the flange nut 16 for water stop. Particularly, a water stop rubber strip 4 is adopted at the upper end fixing part for anchoring the ground surface plane of the basement.

The invention relates to an anti-floating tensile combined anchor rod component (comprising an adhesive anchor rod and an unbonded anchor rod) and a corresponding construction method. When the anchor rod or the finished pipe column is made without the bonding reinforcing steel bars, the bonding reinforcing steel bars can be used as the reinforcing steel bars of the anchor rod in the finished pipe column; the concrete and the reinforcing steel bars in the anchor rod are not bonded, the reinforcing steel bars in the anchor rod can stretch out and draw back or slide in the pipe column or the plastic film sleeve, a post-tensioning method, namely, prestress is applied on a construction site, and the nuts are fastened while the reinforcing steel bars are prestressed.

FIG. 4 is a schematic diagram of a pressure-bearing variable-diameter steel reinforcement cage expanding prestressed anchor rod with anchoring sections at the upper part and the lower part: the foundation 1, the concrete cushion layer 2, the poured anchor rod assembly 3, the water stop rubber strip 4, the flange nut 16, the upper concrete bottom plate 8, the concrete bottom plate steel bar 8-1, the bottom plate cushion layer 8-2 and the steel reinforcement cage 10 can be in a straight-through type or expanded head structure. Grout 12, nut connector 13, guide cap 14, enlarged head 15, flange nut 16 locked on the floor. The nut connector or connecting nut 13 is a screw connection device of finish rolling steel bars, and adopts a nut as a connection structural member to connect threads (from the end part) of the finish rolling steel bars, and the connection strength can be ensured as long as the threads of the finish rolling steel bars enter the nut for a certain length; the length of the connecting nut is 15-25 cm, the standard is 20 cm, the connecting nut can be used for connecting anchor rods with different lengths, can also be used for connecting the anchor rods with main bars of a variable-diameter reinforcement cage, and is also a main bar connecting mode by welding; if the anchor rod element of the finish rolled steel bar is taken as an embodiment: the anchor rods of finish rolled steel bars with the sizes of 3 meters, 4 meters, 5 meters and 7 meters are prepared or prepared, and the finish rolled steel bars with different sizes are connected into the anchor rods with different length requirements by using the connecting nuts 13, for example, two anchor rods with different sizes can be conveniently connected into anchor rod pieces with different lengths from 7 meters to 14 meters. Three anchor rods with different fixed lengths can be conveniently connected into anchor rods with different lengths of 15-21 meters. Four longer anchor members can be made. The anchor rod of the invention adopts a connecting structure at the upper part, a concrete bottom plate 8 and a flange nut 16 are adopted, a bottom plate cushion layer 8-2 is poured on a bottom plate reinforcing steel bar 8-1 of concrete of the concrete bottom plate 8, and the flange nut 16 is used for fixing the concrete bottom plate 8 on the upper surface of a building and the like, so that the anchor rod assembly can anchor a surface layer fixed at the upper end of the building or the anchor rod assembly.

The limiting nut 11 of the enlarged head steel reinforcement cage in fig. 5 (limiting the diameter-variable steel reinforcement cage on the main reinforcement or finish-rolled coarse steel reinforcement 3-1) can also be integrated with the nut connector or connecting nut 13, and the bearing plate nut 16-1 supports the bearing plate at the bottom of the main reinforcement of the steel reinforcement cage 10;

FIG. 6 is a schematic view of the reinforcement structure of the unbonded anchor rod; as shown in fig. 6, the unbonded anchor rod steel bar has the following structure: the anchor rod steel bar (main bar or finish rolling coarse steel bar) 3-1 is positioned in the center, and is firstly wrapped with an anticorrosive layer (anticorrosive grease layer) 3-6, and the outer layer of the anticorrosive layer is a plastic film sleeve 3-5. The unbonded anchor rod reinforcing steel bar can also be provided with a reinforcing steel bar framework 3-7 (the reinforcing steel bar framework is shown in figure 8), and the reinforcing steel bar framework 3-7 is wrapped, solidified and wrapped by concrete or cement mortar, cement paste or other curable materials outside the plastic sleeve, and is called an anchor head. The surface of the main reinforcement steel bar is provided with an anti-corrosive grease layer, and a plastic film sleeve is arranged outside the anti-corrosive grease layer; the anticorrosion grease layer is coated by a anticorrosion grease layer coating device, the anticorrosion grease layer is coated without bonding ribs, a polyethylene or polypropylene plastic film is coated by a plastic extruder, and then a plastic sleeve (pipe) is formed by a cooling cylinder die.

The post-prestress application refers to a main reinforcement steel bar (applying prestress and then fixing by a nut) in the construction process to form a prestress anchor rod assembly. Pre-tensioning prestress, namely pre-stressing force, prefabricating an anchor rod piece: the main reinforcing steel bar is locked by a nut, and the prestressed anchor rod component unit is formed after the prestressed force is applied to the stretching reinforcing steel bar.

FIG. 7 is a schematic view showing a connection structure of anchor rods for a hollow tubular column; the anchor rod reinforcing steel bars can be unbonded or bonded, the unbonded anchor rod reinforcing steel bars are drawn in the drawing, and the hollow pipe column is adopted, so that the expansion and contraction in the pipe column of the anchor rod reinforcing steel bars are not influenced. It can be used for both pre-tensioned and post-tensioned pre-stressed structures. The connecting ends of the hollow pipe columns do not need to be subjected to great forces, but connection of the steel reinforcement cages 3-7 and connection of the concrete between the end ends of the hollow pipe columns are not excluded.

Fig. 8 is a schematic view of a unit and a connection structure of a pretensioned method of anchor bars for hollow pipe columns, the bars may be either unbonded anchor bars or bonded anchor bars, anchor members formed by the bars of the pipe columns of the unit are shown in the drawing, concrete or mortar is poured to prepare the main bars or the outer pipe columns 3-2 of finish rolling coarse bars, the unbonded anchor bars or the bonded anchor bars passing through the central holes of the pipe columns are padded at both ends of the pipe columns by fixing plates or bearing plates 3-4, nuts 3-3 for applying prestress are fixed on the threads of the anchor bars (finish rolling bars), and the anchor bars are screwed when being applied. The nut coupler 13 serves as a coupling means at upper and lower ends of two reinforcing bars.

In contrast, the pre-stressed anchor member units of fig. 8 constitute the most practical assembled structure, especially the pre-stressed anchor member units with pre-tension, the end of each unit is provided with a fixed nut connector or a connecting nut to connect with the steel bar of the unit, the second end of the end of each unit is a protruding steel bar to match with the fixed nut connector of the end of the adjacent unit; the prestressed prefabricated anchor rod units are prepared or prepared into 3, 4, 5 and 7 meter-sized units (net length), and the different sized units are mutually connected into the anchor rod pieces with different length requirements by using the embedded connecting nuts 13, for example, two anchor rod units with different sizes can be conveniently connected into the anchor rod pieces with different lengths from 7 to 14 meters. Three anchor rods with different fixed lengths can be conveniently connected into anchor rod pieces with different lengths of 15-21 meters.

Fig. 4, 5 and 8 show the connection structure of the lower end of the anchor rod with the reducing reinforcement cage and the grouting material or concrete, but the present invention does not exclude other connection structures of the lower end of the anchor rod, including the common reinforcement cage and the grouting material or concrete, and the grouting material or concrete without the reinforcement cage (both the expansion head and the non-expansion head), including the grouting material or concrete wrapped in or wrapped out of the bag.

However, as shown in fig. 9-12, various connecting structures (all of which are enlarged head connecting structures, and non-enlarged head structures are also fully usable, and do not exceed the scope of the present invention) are provided, but more than one reinforcing steel bar in each connecting structure is fixed to the lower end of the anchor rod reinforcing steel bar; the more than one reinforcing steel bar can be a thicker reinforcing steel bar, or a plurality of scattered thin reinforcing steel bars (the total sectional area of the plurality of thin reinforcing steel bars is not less than that of the anchor rod reinforcing steel bars) are uniformly distributed in the grouting body or the concrete.

The non-binding steel bar or common steel bar (generally adopting finish rolling screw thread steel bar) is matched with the hollow anchor rod pipe column of the invention, and can be matched with a pre-tensioned or post-tensioned prestressed anti-floating tensile anchor rod, and the pre-tensioned prefabricated anti-floating tensile steel rod anchor rod member unit can be connected to a steel bar cage with an enlarged head with rated length and variable diameter, thus forming a practical engineering system of the invention.

Considering that the nut connection of the main (bar) steel bar is a threaded connection, it is better to adopt finish-rolled threaded steel bars, and the general thread line cannot have a thread with firm connection.

The anti-floating anti-tensile pre-stressed anchor rod assembly can be combined with a pipe column for a pre-stressed anchor rod, a connecting and anchor locking nut to form a pre-fabricated combined assembled anti-floating anti-tensile pre-stressed anchor rod assembly, can also be used as an independent commodity of a pre-stressed unbonded steel bar component, is used in various anchor rod application schemes for solving the pre-stress problem by adopting a post-tensioning method, and can also be used as a steel bar in a pre-fabricated pre-stressed anchor rod hollow pipe column without setting grease and a sleeve according to design requirements.

The combined assembled unbonded prestressed steel bar part for the anti-floating tensile prestressed anchor rod and the lengthening form thereof can be used for pouring concrete or cement mortar, cement paste or other curable materials to wrap and solidify, and the application of applying the prestressed anchor rod by a prestressed post-tensioning method is independently formed. The lower end of the anchor rod is grafted with a reinforcement cage, an enlarged diameter (variable diameter) reinforcement cage, a fixed diameter reinforcement cage, a bag, an anchor plate or other anchor head bearing bodies arranged in the enlarged footing to form an organic framework whole, concrete or cement mortar, cement paste or other curable materials are poured to wrap the organic framework whole, the organic framework whole is condensed and cured, and stress is applied through a post-tensioning method to form the application of the prestressed anchor rod pile of the enlarged footing.

The main reinforcement and the reinforcing bars can be selected from materials including but not limited to steel, steel strand, glass fiber, resin, glass fiber reinforced resin, aramid fiber, carbon fiber, graphene, carbon-related materials and composites thereof, polymers, high polymer materials, nano materials, metal materials and non-metal materials.

The column reinforcing material of the invention is prestressed by vertical steel bars, steel sleeves, steel reinforcement cages and steel wire mesh cages, then is wrapped by one of concrete or cement mortar, cement paste or other curable materials and is solidified by condensation, and can also be filled into a solid state, thereby forming a prefabricated prestressed column, and can also be used as an independent commodity anchor rod of the prefabricated prestressed column.

The prefabricated combined assembled anti-floating tensile prestressed anchor rod piece, the tubular column for the prefabricated prestressed anchor rod, the prefabricated prestressed unbonded steel bar component for the anti-floating tensile anchor rod and the lengthening form of the prefabricated combined assembled anti-floating tensile prestressed anchor rod piece, the tubular column for the prefabricated prestressed anchor rod and the prefabricated prestressed unbonded steel bar component for the anti-floating tensile anchor rod can be filled with one of concrete or cement mortar, cement paste or other curable materials for coating, and then the concrete or cement mortar, the cement paste or other curable materials are cured by condensation to independently form the application of the prestressed anchor rod body.

The prefabricated combined assembled anti-floating tensile prestressed anchor rod piece and the application thereof are characterized in that the solid geometry of the reinforcement cage comprises but is not limited to: the material is a solid or hollow material, and is in a shape of a cube, polyhedron, regular polyhedron, tetrahedron, cuboid, cylinder, round table, prism, frustum, cone, pyramid, bamboo joint, string or convex-concave; the shape of the planar cross-section includes, but is not limited to: square, rectangle, triangle, quadrilateral, rhombus, trapezoid, polygon, circle, ellipse, ring, sector and bow; the anchor rod member can be solid or hollow in section.

With the arrangement of figure 8, the tubular column of anchor rods of the present invention can also itself constitute a component unit of a hollow anchor, especially a unit (net length) prepared or prepared to a 3, 4, 5, 7 meter scale, with or without adhesive anchor rods being applicable, which is convenient for factory production, and which is weight controllable, low in transportation costs, and easy to control and master in the factory of the quality and criteria of the pre-stressing.

The present invention relates to an anti-floating tensile combined anchor rod component (including two kinds of anchoring steel bar with adhesive and non-adhesive) and its correspondent basically-identical construction method. The construction methods of the pre-tensioning method and the post-tensioning method are different;

the anti-floating tensile combined anchor rod component adopts unbonded anchor rod reinforcing steel bars, common reinforcing steel bars and the finished pipe column, namely the unbonded reinforcing steel bars or the common reinforcing steel bars can be adopted in the finished pipe column as the anchor rod reinforcing steel bars; the concrete and the reinforcing steel bars in the anchor rod are not bonded, the reinforcing steel bars in the anchor rod can stretch out and draw back or slide in the pipe column or the plastic film sleeve, a post-tensioning method, namely, prestress is applied on a construction site, and the nuts are fastened while the reinforcing steel bars are prestressed to form the prestressed anchor rod piece.

In fig. 9, the connecting structure at the lower end of the anchor rod is grouting material or concrete of the enlarged head, main steel bars and a steel reinforcement cage are arranged in the grouting material or concrete, and the bearing plate is sleeved on the main steel bars or the dispersed steel bars and fixed with nuts at the lower end of the bearing plate. FIG. 9 is a schematic view of the construction of the grout or concrete structure of the unbonded or conventional anchor rod and the tapered steel reinforcement cage enlarged head according to the present invention; the reinforcement cage in the grouting body or the concrete can also be a reinforcement cage of a common structure without an expanding structure, but the concrete is an expanding head, the bearing plate is sleeved on the main reinforcement, and the lower end of the bearing plate is fixed by a nut. In fig. 10, the connecting structure at the lower end of the anchor rod is grouting material or concrete of the enlarged head, main reinforcing steel bars or dispersing reinforcing steel bars are arranged in the grouting material or concrete, the grouting material or concrete is combined with the bag, the bag can wrap part of the grouting material or concrete in the central part of the enlarged head, and as shown in the figure, the bearing plate can be sleeved on the main reinforcing steel bars and fixed with nuts at the lower end of the bearing plate. The connection structure at the lower end of the anchor member in fig. 10 is an enlarged head grout or concrete, and is shown as a bladder structure, as shown in the drawings. The main reinforcing steel bars or the dispersing reinforcing steel bars can be arranged in the grouting body or the concrete, the grouting body or the concrete is combined with the main reinforcing steel bars or the dispersing reinforcing steel bars and the bag, and the main reinforcing steel bars penetrate through the central part of the internally wrapped grouting body or the concrete expansion head. The bag can be wrapped externally.

Fig. 11-12 are schematic views of a third, fourth connection configuration of the lower end of a bolt member, particularly a non-bonded bolt; in fig. 11, the connecting structure at the lower end of the anchor rod is grouting material or concrete of the enlarged head, main steel bars are arranged in the grouting material or concrete, but the steel cage is a steel cage with a common structure and has no enlarged diameter structure, and the bearing plate is sleeved on the main steel bars or the dispersed steel bars and is fixed with nuts at the lower end of the bearing plate. In fig. 12, the connecting structure at the lower end of the anchor rod is grouting material or concrete of the enlarged head, main steel bars are arranged in the grouting material or concrete, the steel reinforcement cage is an umbrella-shaped steel reinforcement cage with enlarged diameter, the diameter of the steel reinforcement cage is simply enlarged, and the bearing plate is sleeved on the main steel bars and fixed with nuts at the lower end of the bearing plate.

FIG. 14 is a comparison of FIG. 13 showing two stress bolts with an internal coupling nut coupled to different lengths;

fig. 15 and 16 show two stress anchor rods with embedded and exposed connecting nuts 13 connected in different lengths;

FIG. 18 is a schematic structural view of the steel bar-wrapped concrete with the steel bar frames 3-7 and the bearing plates (provided with steel bar through holes) distributed therein to form a stress anchor rod; in comparison with fig. 17, an in-line coupling nut is provided.

FIG. 19 is a schematic view of a construction in which the reinforced concrete has a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein to form a stress anchor rod; 3-8, pouring concrete at the middle shaft part, wherein 3-1-1 refers to a plurality of anchor rod reinforcing steel bars, and the number of the anchor rod reinforcing steel bars is generally not more than 5; instead of the coupling nut 13, a coupling nut 13 or a nut fixed by applying stress may be provided.

FIG. 20 is a schematic view of a construction of a stress anchor rod in which a steel bar-wrapped concrete has a plurality of main steel bars 3-1-1 and a bearing plate (provided with steel bar through holes) distributed therein; 3-8, pouring concrete at the middle shaft part, and 3-1-1, namely a plurality of anchor rod reinforcing steel bars; a connecting nut 13 or a nut fixed by applying stress can be arranged to replace the connecting nut 13; compared with fig. 20, 2-3 anchor rods are provided.

FIG. 21 illustrates a multi-strand anchor bar 3-1-1 which may be exposed at the ends for connection between anchor member units;

FIG. 22 is a schematic structural view of a steel bar-wrapped concrete anchor rod having a plurality of main steel bars 3-1-1 and a bearing plate (provided with steel bar through holes) distributed therein; but the multi-anchor bar 3-1-1 may be exposed at the ends for connection between anchor member units; the stress nut is used for fixing, and the other end is provided with a connecting nut;

FIG. 23 is a schematic view of the construction of the anchor rod of the present invention in which the reinforced concrete has a plurality of main reinforcing bars 3-1-1 and a bearing plate (provided with reinforcing bar through holes) distributed therein; but the multi-anchor rebar 3-1-1 can be exposed at the ends for connection between the anchor member units and the units. But the unstressed nut is fixed, and the other end is also provided with a connecting nut.

The tubular column of the anchor rod reinforcing steel bar can form a prestressed structure of the hollow anchor rod, is convenient for factory production, has controllable weight and low transportation cost, and the application quality and standard of the prestressed force are easier to control and master in a factory. The outer layer of the main reinforcement or the finish rolling coarse reinforcement (namely the pipe column) prepared by pouring the reinforcement cage with concrete or mortar can resist stress application.

The non-binding steel bar anchor rod can be matched with the hollow anchor rod pipe column, can be matched with pre-tensioning or post-tensioning prestressed anti-floating tensile non-binding anchor rod steel bars, and the pre-tensioning prestressed anti-floating tensile steel bar anchor rod can be connected to an expanded head steel bar cage with rated length and variable diameter, so that a practical engineering system is formed.

The combined anchor rod comprises a concrete prefabricated pipe column, wherein the pipe column is a pipe column for accommodating the anchor rod steel bar, and has an inner diameter of 3-7 cm and an outer diameter of 14-30 cm; the invention relates to a concrete prefabricated pipe column assembly type anti-floating tensile anchor rod assembly, which is characterized in that a steel bar framework can be arranged in the concrete prefabricated pipe column, the steel bar framework of the concrete prefabricated pipe column is provided with a connecting piece at the bottom end, and the connecting piece can be connected with a steel bar cage at the lower end in a fixing mode, particularly in a screwing mode or a welding mode and the like (particularly, the diameter-variable steel bar cage which is proposed by the applicant firstly is connected, particularly, the main bar is connected, the main bar is needed in the center of the diameter-variable steel bar cage, and the pre-stress is not needed for the main bar of the diameter-variable steel bar cage, so that a concrete foundation with the diameter larger than that of the concrete prefabricated pipe column is formed, the foundation is injected by a grouting pipe, and has larger tensile and pressure resisting.

The screw connector of the finish-rolled steel bar adopts a nut as a connecting structural member, the length is 15-25 cm, and the standard is 20 cm.

The finished tubular column is used for fixing the pretensioning type prestress anti-floating tensile reinforcement anchor rod in a prestress mode, the anchor rod reinforcement rod penetrates through the finished tubular column, bearing plates (anchor backing plates) with holes in the centers and larger than the inner diameter of the tubular column are arranged at two ends of the finished tubular column, and when the reinforcement rod ends exposed out of the surfaces of bearing plate holes are stressed, anchor locking nuts are used for fixing the reinforcement rod ends on the bearing plates or welding and fixing the reinforcement rod ends on the bearing plates.

Preparing the reinforcement of the unbonded anchor rod: the extrusion coating process can be adopted, is similar to the process of wrapping the plastic sleeve by the cable, and is suitable for large-scale production of single reinforcing steel bars. Forming an unbonded pre-tensioned or post-tensioned prestressed anti-floating tensile steel bar anchor rod, wherein the anticorrosive grease layer is anticorrosive grease or anticorrosive asphalt; the extrusion coating process is mainly characterized in that the non-adhesive ribs are coated with the anti-corrosion grease layer through a device for coating the anti-corrosion grease layer, the non-adhesive ribs coated with the anti-corrosion grease layer are coated with a polyethylene or polypropylene plastic film through a plastic extruder, and then the plastic sleeve is molded through a cooling cylinder mold. The extrusion coating process has the characteristics of high efficiency, good quality and stable equipment performance, is similar to the process of wrapping plastic sleeves by wires and cables, and is suitable for large-scale production of single steel stranded wires and 2-3 steel wire bundles. The coating forming process is characterized in that after coating is carried out on non-adhesive ribs through a coating groove, the non-adhesive ribs are bundled through a bundling roller and are additionally coated, the thickness of the coating is generally 0.5-2mm, and a sleeve formed by coating anti-corrosion asphalt or anti-corrosion grease (from butter to chlorinated polyethylene) inside and coating plastic cloth outside can be finished through manual operation. Especially, the unbonded tendon coated with anticorrosive grease and other coatings is automatically and alternately wound with two layers of plastic cloth through a cloth winding drum, and is cut into a complete unbonded prestressed tendon after reaching the required length, and the unbonded tendon can also be continuously operated on a paper winding machine to complete the working procedures of bundling, coating anticorrosive grease layers, heading, winding the plastic cloth, cutting and the like. The coating forming process has the characteristics of good quality and strong adaptability. When manufacturing the unbonded prestressed tendon, the steel bar is placed on the anti-wire coil, passes through the comb plate and is converged into a steel wire bundle, the steel wire bundle is uniformly coated with the anti-corrosion grease layer through the oil gun and then penetrates into the anchor ring to be subjected to cold heading by the cold heading machine, the bundled steel wire with the anchor ring is pulled forwards by the tractor, simultaneously, the paper winding turntable provided with the plastic strip is started, and the steel wire bundle winds the plastic strip while advancing. And cutting the steel wire bundle after reaching the required length to form a complete unbonded prestressed tendon.

And (3) post-prestressed anchor rod assemblies, namely locking the (high-strength) steel bars, applying prestress, wrapping the (high-strength) steel bars by using concrete or cement mortar, cement paste or other curable materials, and forming the prefabricated prestressed anchor rod assemblies after the concrete, the cement mortar, the cement paste or the other curable materials are cured.

The method comprises the following steps of (1) preparing a pre-tensioned prefabricated prestressed steel anchor rod 3 unit, wherein the first method and structure are as follows: the main reinforcement in the prestressed anchor rod assembly still adopts a steel bar shown in the figure 1, or two or more steel bars, on a cement precast yard, preset prestress is applied to two ends of the steel bar 3-1, the steel bar is in a relatively elongated tension stress state, at the moment, the tensioned steel bar is poured with concrete or mortar, the diameter of the periphery of the concrete or mortar needs to consider the diameter of a drill rod of the anchor rod during application, and the diameter of the steel bar cage with variable diameter applied in the invention is generally not more than 25cm, or the diameter of the rod piece is set according to engineering requirements; after the poured concrete, mortar or other curable materials are solidified to reach the designed strength, equipment for applying prestress at two ends of the steel anchor rod reinforcing steel bars is loosened, and the prefabricated prestress steel anchor rod piece is prepared. The prefabricated prestressed reinforced concrete anchor rod component with longer relative length can also be prepared, and the full-length prefabricated prestressed reinforced concrete anchor rod component can be disconnected in actual use to obtain the proper application length.

The second method and structure: the pipe columns of the anchor rod reinforcing steel bars can form a multi-unit (each unit can be pre-stressed) prefabricated prestressed structure connected into an anchor rod, each unit is provided with a concrete or mortar pipe column of a main reinforcement or a finish rolling coarse reinforcement outer layer prepared by pouring a reinforcement cage with concrete or mortar and a finish rolling reinforcing steel bar with a corresponding length, and the prestressing force can resist stress application. The multiple units shown in fig. 8 are connected to the required length of the shank member and the screw coupling nut 13 may be embedded.

The lower end of the prefabricated prestressed anchor rod component with the structure can be connected with a variable-diameter steel reinforcement cage, a fixed-diameter steel reinforcement cage, a bag or other anchor heads. When the prefabricated prestressed anchor rod component is connected with a variable-diameter steel reinforcement cage, a fixed-diameter steel reinforcement cage, a bag or other anchor heads, steel reinforcements with the lengths matched with the variable-diameter steel reinforcement cage, the fixed-diameter steel reinforcement cage, the bag or other anchor heads extend out of a reserved position at the lower end of the anchor rod component, and the bottom of the anchor head is connected with an anchor backing plate (in a welding or concrete fixed connection mode and the like); the lower end of the anchor rod component can be provided with a proper length of the reinforcing steel bar and is connected with the top of the finished anchor head by a connecting nut; or the rod piece and the anchor head are improved, so that the prefabricated prestressed anchor rod component, the variable-diameter steel reinforcement cage, the fixed-diameter steel reinforcement cage, the bag or other anchor heads form an organic whole body capable of transferring stress.

The number of the steel bars in the prestressed anchor rod component is one or more than one, such as two, three, four, five or six, so as to form a central bundle structure (for example, it is difficult to design a single steel bar to be subjected to rough machining), and the specification, performance and diameter of the steel bars can be determined according to the requirements of the specific prestress required by the design and the application requirement of the tension of the anchor rod (refer to the design manual of the anchor rod); the length, the shape and the area of the cross section of the anchor rod are set according to specific engineering technical requirements. Various specification standards can be established for standardized production. One or more threaded steel bars, namely steel bar anchor rod holes, are arranged on the anchor backing plate. The prestressed anchor rod formed by the plurality of steel bar anchors is good in effect, so that the prestressed anchor rod is stressed more uniformly, and stress application is more uniform.

The materials used for the main reinforcement and the reinforcing bar of the steel bar anchor rod include, but are not limited to, steel strand, glass fiber, aramid fiber or other high polymer material fiber, carbon fiber, graphene, carbon element-related materials and composite materials thereof. Polymer materials such as carbon fiber can also be used for the anchor rod, and the spiral stress is also good.

The prestressed anchor rod solid body can be solid, the section that can also be hollow means that different casting materials are used, and a cylinder shape can be cast after the core is fixed.

The invention particularly relates to an application of a pre-tensioned pre-stressed anchor rod assembly, which is applicable to the fields of but not limited to anti-floating tensile, road, mining, tunnel bridge, foundation pit and mountain slope protection and geological disaster treatment; also used in the fields of pressure-resistant engineering and the like. The pile can be used as a prefabricated prestressed compression-resistant pile according to the requirements of engineering design purposes.

The prestressed anchor rod prestress construction method for the straight-through or variable-diameter steel reinforcement cage expansion body is characterized in that the straight-through or variable-diameter steel reinforcement cage and a pull rod are fixed, a pile machine drills a hole to a depth, high-pressure jet grouting construction or mechanical hole expansion construction can be carried out, a prestressed anchor rod with a certain diameter is put down, the bottom end of an anchor rod is the straight-through or variable-diameter steel reinforcement cage, an expansion mechanism opens the steel reinforcement cage to a designed size after the variable-diameter steel reinforcement cage is in place, and high-pressure grouting or concrete pouring is carried out on an expansion section and the; the pull rod in the prestressed anchor rod is pre-stressed to form a prefabricated part of prestressed reinforced concrete;

the application method comprises the following steps: (1) drilling to a designed depth, carrying out high-pressure jet grouting construction or mechanical drilling or reaming construction, and after pore forming, (2) prefabricating a combined assembly type anti-floating tensile prestressed anchor rod piece, a prefabricated pipe column for the pre-stressed anchor rod, a prefabricated prestressed non-adhesive reinforcing steel bar part for the anti-floating tensile anchor rod and a lengthening form thereof according to design requirements, or a framework system which is grafted with a reinforcing cage, an enlarged diameter (variable diameter) reinforcing cage, a variable diameter reinforcing cage, a fixed diameter reinforcing cage, a bag, an anchor plate or other anchor head bearing bodies arranged at the enlarged bottom end part, and (3) when stress is applied by a post-tensioning method, fixing by using a flange nut (complete set) after the stress is applied; (4) pouring concrete or cement mortar, cement paste or other curable materials to wrap one of the materials, solidifying and independently forming a prestressed anchor rod body or forming an expanded head prestressed anchor rod pile, and (5) finally, installing a formwork and pouring a concrete foundation slab fixing anchor. The use of a pre-stressed anchor rod assembly does not require post-stressing.

Magnitude of applied prestress: when the anti-floating calculation is carried out according to the basement, the calculated floating water head is amplified by 1.05 times; the safety coefficient of the anti-floating calculation prestressed anchor rod is K equal to 2.0; therefore, the prestress applied by the prestressed anchor is smaller than the characteristic value of the prestressed anchor and is larger than the anti-buoyancy force of the prestressed anchor required by the normal water level, and the characteristic value of the bearing capacity is taken into comprehensive consideration of 50%. In the preparation of pre-stressed anchors, different diameters have different applied pre-stresses (different elongations, different relative elongation coefficients).

The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A prefabricated combined assembled anti-floating tensile prestressed anchor rod piece is characterized by comprising unbonded steel bars or main steel bars, a hollow pipe column for the prestressed anchor rod and a nut for locking an anchor; and (3) penetrating unbonded steel bars or main steel bars into the pipe column, taking the prefabricated hollow pipe column as a support, tensioning two ends of the steel bars, applying prestress, and locking the steel bars at two ends of the pipe column by nuts to form a prefabricated prestressed anchor rod piece.

2. The pre-stressed unbonded steel bar for the anti-floating tensile anchor rod as claimed in claim 1, wherein the main reinforcement steel bar is high-strength finish-rolled deformed steel bar; and an anti-corrosion grease layer is arranged on the surface of the main reinforcement steel bar, and a sleeve is arranged outside the anti-corrosion grease layer to form the pre-stressed unbonded steel bar.

3. The prestressed anchorage bar of claim 2, wherein the unbounded steel bars, the main reinforcement bars are main reinforcement bar structures connecting the segmented main reinforcement bars through the connecting nuts, the number of the main reinforcement bars is one or from one to 6 parallel steel bars, the main reinforcement bars are uniformly distributed in the center of the prestressed anchorage bar, the main reinforcement bars are selected from threaded round steel, steel pipes, steel strands or section steel, the steel pipes and the section steel are provided with threads at both ends, and the sleeves are metal foils and plastic sleeves.

4. The prestressed anchorage bar of claim 1, wherein the hollow pipe column for the prestressed anchorage bar is a pipe column prefabricated by concrete and provided with a steel reinforcement framework, the pipe column can accommodate unbonded steel bars for the anchorage bar, the inner diameter is 3-7 cm, the outer diameter is 10-30 cm, the size can be set according to engineering requirements, the pipe column prefabricated by concrete is provided with or without the framework, the framework is selected from reinforcement materials, selectable reinforcement materials include but are not limited to a plurality of vertical steel bars, stirrups, steel sleeves, steel reinforcement cage steel wire mesh cages, bearing plates, anchoring plates, bearing flanges and the like, and the reinforcement materials and one of concrete or cement mortar, cement paste or other curable materials are wrapped and are solidified to form the pipe column.

5. The prestressed anchorage member of claim 1 or 4, wherein the prestressed anchorage member is a hollow tubular column, and is prepared by applying prestress to vertical reinforcement of reinforcing material, steel sleeve, reinforcement cage and wire mesh cage, then wrapping with one of concrete or cement mortar, cement paste or other curable materials, solidifying, or filling into a solid state, thereby forming a prestressed tubular column, or using as a commercial anchor rod component independent of the prestressed tubular column.

6. The prestressed anchorage bar of claim 1 or 3, wherein the anchor-locking nut and the connecting nut are externally or internally embedded in a pipe string and integrated with the pipe string for the prestressed anchorage bar, and the connecting nut connects two or more prestressed anchorage bar members to achieve a desired length.

7. The prestressed anchorage member of any one of claims 1 to 6, wherein the pipe column for the prestressed anchorage member, the prestressed unbounded steel bar for the anti-floating tensile anchorage member and the lengthening form thereof are assembled to form the anti-floating tensile prestressed anchorage member, and the pre-stressed anchorage member is independently formed by pouring one of concrete or cement mortar, cement paste or other curable materials to wrap the one and curing the one; and grafting the expanded prestressed anchor pile with a reinforcement cage, an expanded diameter (variable diameter) reinforcement cage, a variable diameter reinforcement cage, a fixed diameter reinforcement cage, a bag, an anchor plate or other anchor head bearing bodies arranged at the expanded bottom end part, and pouring one of concrete or cement mortar, cement paste or other curable materials for coating, solidifying and forming the expanded head prestressed anchor pile under the condition of applying stress.

8. The prestressed anchor bar of any one of claims 1 to 6, wherein said anchor bar, reinforcement cage, solid geometry includes but is not limited to: cube, polyhedron, regular polyhedron, tetrahedron, cuboid, cylinder, round platform, prism, terrace with edges, circular cone, pyramid, bamboo joint, cluster, convex-concave, the shape of plane cross section includes but not limited to: square, rectangle, triangle, quadrilateral, rhombus, trapezoid, polygon, circle, ellipse, ring, sector and bow; the anchor rod member can be solid or hollow in section.

9. The prestressed anchorage member of any one of claims 1 to 6, wherein said pipe column for prestressed anchorage, said prestressed unbounded reinforcement for anti-floating tensile anchorage, and said elongated form of main reinforcement and reinforcing reinforcement are made of materials including but not limited to steel, steel strand, glass fiber, resin, glass fiber reinforced resin, aramid fiber, carbon fiber, graphene, carbon-related materials and composites thereof, polymer, high-molecular polymer material, nanomaterial, metal material, and non-metal material.

10. The application method of the prefabricated combined assembly type anti-floating tensile prestressed anchor rod assembly according to one of claims 1-7, characterized by comprising the following steps: drilling to a designed depth, carrying out high-pressure jet grouting construction or mechanical reaming construction, placing an anchor rod steel bar piece to be connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other anchor heads after forming a hole, releasing a restraint mechanism to expand the variable-diameter steel bar cage to a designed size after an expansion head with the variable-diameter steel bar cage is in place, and then pouring grout or pouring concrete into the expansion section of the variable-diameter steel bar cage to form the anchor head; the top of the anchor rod steel bar is fixed by a flange nut sleeve embedded in and sleeved with the steel bar, or can be fixed by an anchor plate and a nut and connected with a steel bar framework system of the foundation slab, and the post-tensioning method applied stress is fixed by the flange nut sleeve when the post-tensioning method is applied stress; grouting or pouring concrete into the gap between the steel bar and the hole to complete the prestressed anchor rod piece; finally, installing a formwork and pouring a concrete foundation slab fixing anchor plate; the use of a pre-stressed anchor rod assembly does not require post-stressing.

11. The application method as claimed in claim 10, wherein the steps are as follows: when the anchor rod assembly is connected with a variable-diameter steel bar cage, a fixed-diameter steel bar cage, a bag or other anchor heads, steel bars with the length suitable for the variable-diameter steel bar cage, the fixed-diameter steel bar cage, the bag or other anchor heads are reserved at the lower end of the anchor rod assembly, the bottom of the anchor head is connected with an anchor backing plate (the steel bars are welded or main steel bars are connected through connecting nuts), and the proper length of the steel bars is reserved and is connected with the top of the finished anchor head through the connecting nuts; by improving the rod piece and the anchor head, the anchor rod assembly and the variable-diameter reinforcement cage, the fixed-diameter reinforcement cage, the bag or other anchor heads form an organic whole.