CN111236218A

CN111236218A - Glass fiber reinforcement and steel bar combined anti-floating pile and construction method thereof

Info

Publication number: CN111236218A
Application number: CN202010218596.8A
Authority: CN
Inventors: 左皓; 吴洪伟; 吴富勇; 廖乃凯; 陈莉; 丘强; 张晓刚; 唐光暹; 尹传勇; 陈江雪; 陈杰; 胡越; 容睿俊; 张世武
Original assignee: Guangxi Beitou Decoration Co Ltd
Current assignee: Guangxi Beitou Decoration Co Ltd
Priority date: 2020-03-25
Filing date: 2020-03-25
Publication date: 2020-06-05

Abstract

The invention discloses a glass fiber reinforcement and steel bar combined anti-floating pile and a construction method thereof, wherein the anti-floating pile comprises a concrete pile body and a reinforcement cage arranged inside the concrete pile body, wherein the reinforcement cage comprises a plurality of main reinforcements, GFRP spiral stirrups, annular reinforcing steel bars and anchoring steel bars; the central shafts of all the annular reinforcing steel bars are superposed on the same straight line extending along the longitudinal direction; the main reinforcements extend along the longitudinal direction and are uniformly distributed on the outer sides of the annular reinforcing steel bars; the GFRP spiral stirrup surrounds the outer side of the main reinforcement; the main reinforcement comprises a plurality of GFRP reinforcements and at least 3 reinforcements, and the GFRP reinforcements positioned at the top of the reinforcement cage are all anchored in the bearing platform through anchoring reinforcements. The invention uses the glass fiber reinforcement and the steel bar in a matching way, solves the problem that the GFRP reinforcement is easy to damage and can not be tightly connected with the bearing platform in the pile head chiseling process, shortens the construction period, saves the cost, has strong popularization and has wide application prospect in the field of anti-floating pile foundation engineering.

Description

Glass fiber reinforcement and steel bar combined anti-floating pile and construction method thereof

Technical Field

The invention belongs to the technical field of anti-floating piles, and particularly relates to a glass fiber reinforcement and steel bar combined anti-floating pile and a construction method thereof, which are suitable for rotary drilling and drilling cast-in-place anti-floating piles and cast-in-place anti-floating piles in other hole forming forms.

Background

The GFRP bar (glass-fiber-reinforced plastic bar) is a new type of organic composite material, which is a rod body material made up by using longitudinal continuous glass fiber and a thermosetting polymer resin through the processes of pultrusion and surface treatment, and the obtained fiber polymer surface is spirally wound by glass fiber bundle, and is wrapped with resin to form the teeth similar to reinforcing bar so as to raise the binding property with concrete. Compared with the common steel bar, the GFRP steel bar has the advantages of light weight, high tensile strength, high static shearing force, low dynamic shearing force, high corrosion resistance, low elastic modulus and the like, is widely applied to various fields such as shipbuilding, electric power, traffic, buildings and the like, is mainly applied to underground engineering and structural engineering in the field of construction, is mature in underground engineering, is mainly used for supporting piles, continuous walls, anchor rods and soil nails in foundation pit supporting, and is rarely applied to structural engineering.

Although the GFRP ribs have good toughness, the rib cage made of the GFRP ribs is easy to deform and poor in stability, and the GFRP ribs cannot be connected in a welding mode, so that the GFRP ribs are not easy to process into the rib cage, and the rib cage is not easy to be used for anti-floating pile construction; in addition, the shearing resistance of the GFRP rib is far weaker than that of a common steel bar, so that the GFRP rib is easy to damage in the pile head breaking process and cannot be tightly connected with a bearing platform.

Disclosure of Invention

The invention aims to solve the problems in the prior art, and provides a glass fiber reinforcement and steel bar combined anti-floating pile and a construction method thereof.

In order to achieve the purpose, the invention adopts the following technical scheme:

a kind of glass fiber reinforcement and combined anti-floating pile of steel reinforcement, including the concrete pile shaft and rib cage placed in the concrete pile shaft, the said rib cage includes many main reinforcement, GFRP spiral stirrup, annular reinforcement bar and anchor bar; the central shafts of all the annular reinforcing steel bars are superposed on the same straight line extending along the longitudinal direction; the main reinforcements extend along the longitudinal direction and are uniformly distributed on the outer sides of the annular reinforcing steel bars; the GFRP spiral stirrup surrounds the outer side of the main reinforcement; the main reinforcement comprises a plurality of GFRP reinforcements and at least 3 reinforcements, and the GFRP reinforcements positioned at the top of the reinforcement cage are all anchored in the bearing platform through anchoring reinforcements.

Preferably, the part of the anchoring steel bar extending out of the bottom of the bearing platform is overlapped with the upper end of the GFRP bar through at least two buckling pieces, and the length of the overlapped part is not less than 2 m.

Preferably, the upper and lower adjacent main ribs are overlapped through at least two fasteners, and the length of the overlapped part is not less than 44 times of the diameter of the main rib.

Preferably, the fastener is a U-bolt.

Preferably, the GFRP rib and the annular reinforcing steel bar at the top of the rib cage, and the GFRP rib and the GFRP spiral stirrup are bound and fixed by non-galvanized steel wires.

Preferably, the steel bar cage further comprises a pair of positioning steel bar rings symmetrically arranged at the top of the steel bar cage, and a cross bar penetrating into the pair of positioning steel bar rings.

Preferably, the GFRP rib and the GFRP spiral stirrup are both made of alkali-free glass fibers with the alkali content of less than 0.8%; the resin matrix adopts any one or two mixed resins of vinyl resin and epoxy resin, and the raw material polymer of the resin matrix does not contain polyester component.

A construction method of a glass fiber reinforcement and steel bar combined anti-floating pile comprises the following steps of manufacturing a reinforcement cage:

(1) manufacturing required annular reinforcing steel bars according to the designed size, vertically welding the reinforcing steel bars to the outer sides of the annular reinforcing steel bars, enabling the central shafts of all the annular reinforcing steel bars to be superposed on the same straight line extending along the longitudinal direction, binding a plurality of GFRP bars to the outer sides of all the annular reinforcing steel bars, and enabling the GFRP bars to be parallel to the reinforcing steel bars;

(2) binding and fixing the GFRP rib and the annular reinforcing steel bar at the top of the rib cage;

(3) encircling the GFRP spiral stirrup on the outer side of the main reinforcement and binding and fixing the GFRP spiral stirrup;

(4) GFRP ribs on the top of the rib cage are all anchored in the bearing platform through anchoring reinforcing steel bars.

The construction method of the glass fiber reinforced plastic and steel bar combined anti-floating pile specifically comprises the following steps:

s1, pile position measuring and placing: measuring pile positions according to the coordinates of the wire points and the engineering points; pile protection points are measured and set out at four corners of a pile at the center of the hole site and are used as pile site control points and check points in drilling;

s2, manufacturing and embedding of a protective cylinder: a lifting lug is welded on the outer side of the pile casing, and a slurry outlet is formed in the top of the pile casing; the central vertical line of the pile casing coincides with the central line of the pile, and the top end of the pile casing is higher than the ground/water surface; leveling and aligning a protective cylinder in the pit, symmetrically and uniformly backfilling clay around the protective cylinder, and symmetrically tamping in a layered manner;

s3, positioning the pile driver: moving the rotary drilling rig to a drilling platform, rechecking the central hanging line of the cross-shaped pile guard, aligning the centers of the drill rod and the drill bit with the central point of the pile position, and rechecking by using a vertical line;

s4, slurry preparation: preparing mud with corresponding performance indexes according to a drilling method and the stratum condition;

s5, drilling: in the drilling process, a slag sample is extracted at regular time and checked with a survey stratum, and the drilling speed and the drilling pressure are adjusted according to different stratums; after the drilling is estimated to reach the designed elevation, the drilling is stopped after the initial judgment of the rock sample and the judgment and confirmation of the depth of the measuring rope detection hole are in place;

s6, hole cleaning and hole checking: cleaning holes by adopting a rotary digging bucket, and measuring the depth, the aperture and the inclination of the holes after cleaning the holes;

s7, manufacturing a rib cage:

s7.1, required annular reinforcing steel bars are manufactured according to the design size, the reinforcing steel bars are welded on the outer sides of the annular reinforcing steel bars one by one, the central axes of all the annular reinforcing steel bars are overlapped on the same straight line extending along the longitudinal direction, GFRP bars are bound on the outer sides of all the annular reinforcing steel bars, and the GFRP bars and the reinforcing steel bars are kept parallel;

s7.2, binding and fixing the GFRP rib and the annular reinforcing steel bar at the top of the rib cage;

s7.3, winding the GFRP spiral stirrup on the outer side of the main reinforcement in a surrounding manner, and binding and fixing;

s7.4, anchoring the upper end of the anchoring steel bar in the bearing platform, extending the lower end of the anchoring steel bar out of the bottom of the bearing platform, and lapping the upper end of the GFRP bar through at least two buckling pieces;

s8, placing a reinforcement cage:

s8.1, symmetrically and uniformly arranging concrete cushion blocks on the outer side of the reinforcement cage;

s8.2, hanging the rib cage in alignment with the hole site;

s8.3, fixing the reinforcement cage at the elevation position after the reinforcement cage is sunk to the designed position;

s8.4, determining the length of the hanging rib according to the elevation of the top surface of the pile casing and the elevation of the top surface of the reinforcement cage, and fixing the hanging rib on the top of the pile casing by penetrating a steel pipe through the hanging rib;

s9, installing a guide pipe: after the guide pipe is assembled, the guide pipe is put into the center of the hole;

s10, secondary hole cleaning: injecting the slurry into the hole bottom through a guide pipe by using a slurry pump to drive the sediment to float upwards and flow out of the hole;

s11, pouring concrete: adopting underwater concrete pouring, and continuously pouring concrete after the first batch of concrete mixture falls; in the pouring process, the height of the concrete surface in the hole is detected, the embedding depth of the guide pipe is calculated, and the embedding depth is adjusted in time; and pouring concrete with the height of 0.5-1.0 m above the designed elevation of the pile top, and removing the concrete before partial pile extension.

Preferably, the step S7 of manufacturing the cage further includes welding a pair of positioning reinforcing rings symmetrically on the top of the cage, and inserting a cross bar from the positioning reinforcing rings to fix the cage at the elevation.

Compared with the prior art, the invention has the advantages that:

the invention provides a glass fiber reinforcement and steel bar combined anti-floating pile and construction thereof, which have the following advantages:

(1) the anti-floating pile adopts the GFRP rib and a small amount of steel bars as main ribs, the characteristic of high tensile strength of the GFRP rib is fully exerted, the manufacturing cost of the anti-floating pile is reduced by about 20% compared with the manufacturing cost of the anti-floating pile adopting the steel bars under the same condition, the engineering cost can be reduced, energy is saved, emission is reduced by adopting the GFRP rib made of organic synthetic materials to replace the steel bars, and the requirements of environment protection and green construction are met;

(2) according to the reinforcement cage, the annular reinforcing steel bars are used as the framework, and the GFRP bars and the reinforcing steel bars are mixed and matched to be used as the reinforcement cage made of the main bars, so that the problems that the GFRP bars are not easy to process into the reinforcement cage and the GFRP bars are easy to deform and poor in stability are solved;

(3) because the GFRP rib belongs to the brittle material, the shearing resistance is very low, and is easy to be destroyed, if the GFRP rib is directly anchored in the bearing platform, then in the floating slurry removing process, the GFRP rib is easy to be destroyed, and the anti-floating pile and the bearing platform can not be tightly connected. Therefore, when the anti-floating pile is connected with the bearing platform, each GFRP rib at the top of the rib cage is connected with the bearing platform through the anchoring steel bar in the 2m range in a lap joint mode through the clamping piece, the corresponding anchoring steel bar is tightly connected with the bearing platform even if the GFRP rib is damaged in the floating slurry removing process of the anti-floating pile top, and the problem that the GFRP rib cannot be tightly connected with the bearing platform due to the fact that the GFRP rib is easy to damage in the pile head chiseling-removing process is solved.

Drawings

Fig. 1 is a schematic structural view of a fiberglass reinforced plastic and steel bar combined anti-floating pile according to the present invention.

Fig. 2 is a schematic view showing the connection of the main reinforcement, the GFRP spiral stirrup, and the ring-shaped reinforcing steel bar according to the present invention.

Fig. 3 is a schematic view showing the connection of the GFRP rib of the present invention to the anchoring bar.

Fig. 4 is a construction flow chart of the glass fiber reinforced plastic and steel bar combined anti-floating pile of the present invention.

Reference numerals: 1-concrete pile body, 2-reinforcement cage, 21-main reinforcement, 211-GFRP reinforcement, 212-reinforcement, 22-GFRP spiral stirrup, 23-annular reinforcing reinforcement, 24-anchoring reinforcement, 25-positioning reinforcement ring, 26-cross bar, 27-fastener and 3-bearing platform.

Detailed Description

The technical solution of the present invention is further described in non-limiting detail with reference to the following examples and the accompanying drawings.

As shown in fig. 1 to 3, a combined anti-floating pile of glass fiber reinforcement and steel reinforcement comprises a concrete pile body 1 and a reinforcement cage 2 arranged inside the concrete pile body, wherein the reinforcement cage comprises a plurality of main reinforcements 21, GFRP spiral stirrups 22, annular reinforcing steel bars 23 and anchoring steel bars 24; the central axes of all the annular reinforcing steel bars 23 are superposed on the same straight line extending along the longitudinal direction; the main reinforcements extend along the longitudinal direction and are uniformly distributed on the outer sides of the annular reinforcing steel bars; the GFRP spiral stirrup surrounds the outer side of the main reinforcement; the main reinforcement 21 comprises a plurality of GFRP reinforcements 211 and 3-4 reinforcements 212, and the GFRP reinforcements 211 at the top of the reinforcement cage are all anchored in the bearing platform 3 through anchoring reinforcements 24.

The part of the anchoring steel bar 24 extending out of the bottom of the bearing platform 3 is overlapped with the upper end of the GFRP bar 211 through at least two fasteners 27, and the length h of the overlapped part is not less than 2 m.

When the main ribs are not long enough, the main ribs can be additionally lapped below, the upper and lower adjacent main ribs are lapped through at least two buckling pieces 27, and the length of the lapped part is not less than 44 times of the diameter of the main ribs.

In order to ensure the stability and reliability of the connection of the longitudinal main ribs, the buckling pieces 27 are arranged at intervals up and down, so that the rib cage can be prevented from generating excessive deformation; the fastener adopts steel U type bolt, and U type bolt diameter and main muscle diameter looks adaptation.

And non-galvanized steel wires are used for binding and fixing the GFRP rib 211 and the annular reinforcing steel bar 23 at the top of the reinforcement cage and the GFRP rib 211 and the GFRP spiral stirrup 22.

The cage 2 further comprises a pair of spacer rings 25 symmetrically disposed on top of the cage, and a bar 26 penetrating the pair of spacer rings, the bar being inserted from the spacer rings for fixing the cage at the elevation.

The glass fibers in the GFRP rib 211 and the GFRP spiral stirrup 22 are both made of alkali-free glass fibers with the alkali content of less than 0.8 percent; the resin matrix adopts any one or two mixed resins of vinyl and epoxy resin, and the raw material polymer of the resin matrix does not contain polyester component. The main reinforcement of the embodiment is made of phi 25GFRP reinforcement and phi 25HRB 400-grade reinforcement; the GFRP spiral stirrup is made of phi 8GFRP ribs; the anchoring steel bar is made of phi 25HRB 400-grade steel bars; the annular reinforcing steel bar is made of phi 16HRB 400-grade steel bars.

As shown in fig. 4, the construction method of the glass fiber reinforced plastic and steel bar combined anti-floating pile specifically includes the following steps:

s1, pile position measuring and placing:

the method is characterized in that the method follows the principle from whole to local during measurement, each pile position is positioned and lofted by a conducting wire point which is calibrated through repeated measurement, and the main content of the measurement comprises the following steps: the central pile position of each pile position and the cross pile guard surrounding the central pile are simultaneously measured to obtain the ground elevation of the pile position. When the pile position is lofted, the distance between the cross pile guards and the central pile is not less than 2m, and the cross pile guards are buried stably.

Measuring the pile position by a total station according to a design drawing and the coordinates of the lead point and the engineering point; pile protection points are measured and set out at four corners of a pile at the center of the hole site and are used as pile site control points and check points in drilling;

s2, manufacturing and embedding of a protective cylinder:

the diameter of the protective cylinder is related to the diameter of the drill bit and a hole forming method: forming a hole by an impact method, wherein the inner diameter of the protective cylinder is 200-400 mm larger than the diameter of the drill bit; the length of each section of protective cylinder is generally 1.5-2.0 m according to needs.

S2.1 manufacturing of protective cylinder

(1) The protective cylinder is a reusable device, is firm and durable in structure and convenient to install and remove, and is made of steel, and is formed by rolling a steel plate, and the thickness of the steel plate is 4-12 mm;

(2) in order to facilitate hoisting, 3-4 lifting lugs are welded on the outer side of the pile casing;

(3) the joint of the protective cylinder requires no protrusion in the cylinder, and the cylinder is resistant to pulling and pressing and does not leak water;

(4) in order to facilitate the circulation of the slurry, a slurry outlet with the height of 400mm and the width of 200mm is arranged at the top of the protective cylinder;

s2.2 embedding of protective cylinder

(1) The vertical line of the center of the pile casing coincides with the center line of the pile, the plane tolerance is 50mm, and the inclination of the vertical line is not more than 1%;

(2) the top of the pile casing is 0.3-0.5 m higher than the ground; when the water is in water, the water surface is 1.0-2.0 m higher than the water surface;

(3) the embedding depth of the pile casing is determined according to design requirements or pile diameter and hydrogeological conditions, the embedding depth is 2-4 m, and special conditions are deepened to ensure that drilling and pile concrete pouring are carried out smoothly;

(4) positioning the pile casing in place by a cross method, leveling and aligning the pile casing in the pit, symmetrically and uniformly backfilling clay with optimal water content around the pile casing, and ramming symmetrically in layers to prevent the pile casing from inclining;

s3, positioning the pile driver:

slowly moving the rotary drilling rig to the drilling platform, and adjusting the rotary drilling rig to enable the pile hole to be within the working range of the drilling rig; before centering, a rotary drilling rig rechecks the central hanging line of the cross pile guard, after meeting the standard requirement, starting a computer automatic reset device, adjusting the drilling rig to align the centers of a drill rod and a drill bit with the central point of a pile position, and rechecking by using a vertical line;

s4, slurry preparation:

preparing mud with corresponding performance indexes according to a drilling method and the stratum condition;

ordinary mud is the mixture of clay and water, because the hydrostatic pressure of mud is bigger than water, can form one deck mud skin on the borehole wall, separation hole seepage flow outward, prevents the hole that collapses, and mud performance index is as shown in table 1:

TABLE 1

The settling pond and the slurry storage pond are arranged on site, pile holes close to each other can share one system, the positions and the sizes of the slurry pond and the settling pond are adjusted according to local conditions, and drilling slag in the slurry tank and the sludge pond is fished at any time in the drilling process.

S5, drilling:

when drilling, firstly, drilling at a low speed with a low gear, and adjusting the speed to a normal speed after drilling to 1 m below the pile casing; in the drilling process, different types of drill bits are selected according to different geological conditions, and a spiral earth drill or a rotary digging bucket is selected as the drill bit in the soil or the fine-angle gravel soil stratum; in the drilling process, a slag sample is extracted at regular time and checked with a survey stratum, and the change of the soil layer is noticed so as to adjust the drilling speed and the drilling pressure aiming at different stratums in time; after the drilling is estimated to reach the designed elevation, the drilling is stopped after the initial judgment of the rock sample and the judgment and confirmation of the depth of the measuring rope detection hole are in place;

s6, hole cleaning and hole checking:

after the drilling is carried out to the designed depth, cleaning the hole by adopting a rotary digging bucket, closely watching the depth display value on a computer, when the display value is the drilling depth display value, rotating forward 4-5 turns in situ to enable sediments at the bottom of the hole to be screwed into the containing bucket, cleaning the bottom of the hole to be flat by using flat-bottom bucket teeth of the rotary digging bucket, and then lifting out the rotary digging bucket to discharge the sediments; in order to ensure that the sediment at the bottom of the hole meets the requirements, the depth of the hole is detected by using a measuring rope after the sediment is taken for the first time, if the measured depth is consistent with the drilling depth, the hole is qualified for cleaning, otherwise, the rotary digging bucket is used again to continuously clean the sediment until the sediment is qualified; after cleaning the hole, measuring the hole depth in time by using a measuring rope, detecting various indexes such as the aperture, the inclination of the hole and the like by using a hole detector, wherein the hole detector is made of a steel reinforcement cage, the outer diameter of the hole detector is equal to the designed aperture, and the length of the hole detector is equal to 4 times of the aperture; the method of forced insertion of the hole inspection device is strictly forbidden to carry out hole inspection.

After the hole depth, the hole diameter and the inclination are detected to be qualified, entering the next procedure, measuring the hole depth again before lowering the reinforcement cage and pouring concrete, and checking whether a hole collapse phenomenon exists; and when hole collapse occurs or sediment is too thick, the rotary digging bucket is used for secondary hole cleaning in time.

S7, manufacturing a rib cage:

s7.1, required annular reinforcing steel bars are manufactured according to the design size, the positions of all main bars are marked on the annular reinforcing steel bars, and the positions of all the annular reinforcing steel bars are marked on all the main bars; welding 3-4 HRB 400-grade steel bars on the outer sides of the annular reinforcing steel bars one by one vertically according to marks, enabling the central axes of all the annular reinforcing steel bars to be superposed on the same straight line extending along the longitudinal direction, then binding each GFRP bar on the outer side of each annular reinforcing steel bar in sequence by adopting non-galvanized steel wires, and keeping the GFRP bars and the steel bars parallel;

s7.2, binding and fixing the GFRP rib and the annular reinforcing steel bar at the top of the rib cage by using a non-galvanized steel wire;

s7.3, spirally surrounding the GFRP spiral stirrup at the outer side of the main reinforcement at the interval of 200mm, and binding and fixing the GFRP spiral stirrup by adopting a non-galvanized steel wire;

s7.4 the upper end of the anchoring steel bar is anchored in the bearing platform, the lower end of the anchoring steel bar extends out of the bottom of the bearing platform and is in lap joint with the upper end of the GFRP bar through at least two buckling pieces, and the length of the lap joint part is not less than 2 m.

S8, placing a reinforcement cage:

s8.1, symmetrically arranging a group of concrete cushion blocks at the outer side of the reinforcement cage, and arranging one concrete cushion block every 2m along the extension direction of the reinforcement cage so as to ensure the thickness of a protective layer; before the reinforcement cage is lowered, a hole detector is used for detecting the formed hole, and the reinforcement cage can be lowered under the condition that the formed hole has no quality problem; removing impurities at the orifice, and placing an operation surface springboard and a reinforcement cage cross arm sleeper;

s8.2, hanging the reinforcement cage into the hole by aligning with the hole position, keeping the pile body vertical, lightly placing and slowly entering the hole, and preventing left and right rotation; if the downward movement is obstructed, stopping the downward movement, finding out the reason for processing, and strictly prohibiting the upward movement and the downward forced movement; the hoisting reinforcement cage is stable, is slowly put down after being aligned with the pile hole, does not collide with the well wall, and is commanded by a special person;

s8.3, after the reinforcement cage is sunk in place, centering adjustment is carried out, and then a cross bar is inserted into a pair of positioning reinforcement rings at the top of the reinforcement cage, so that the reinforcement cage is fixed at the elevation position, and the displacement and sinking of the reinforcement cage are prevented; the reinforcement cage and the orifice protecting cylinder can also be temporarily welded;

s9, installing a guide pipe:

the guide pipe is made of a steel pipe with the diameter of 200-250 mm, each section is 2-3 m, the length of the bottom section is 4m, and 1-2 sections of short pipes with the length of 1-1.5 m are matched; the pipe connector is firmly connected and tightly closed, the pipe connector is clean and free of sundries, the sealing rubber ring is free of damage and aging, the verticality and the sealing performance after assembly are checked, the assembly length of the pipe is determined according to the pile depth, the pipe is located in the center of the pile hole during hoisting, and a lifting test is carried out before pouring; the deviation of the axis of the assembled conduit does not exceed 0.5 percent of the depth of the pile hole and is not more than 10 cm; numbering the outer wall of the conduit section by section from bottom to top by using obvious marks and marking the scale;

s10, secondary hole cleaning:

after the conduit is placed and before concrete is poured, secondary hole cleaning is carried out by adopting a positive circulation hole cleaning method, mud is injected into the bottom of the hole from the conduit by a mud pump, and precipitates are driven to float upwards and flow out of the hole;

s11, pouring concrete:

(1) the concrete is poured underwater, the strength grade of the cement is not lower than 42.5, and is 1.5-2 times of the strength of the designed concrete; the concrete mixture has good workability, no obvious segregation and bleeding phenomena, good fluidity, slump of 180-220 mm, and the time for keeping the slump reduced to 150mm is not less than 1 hour;

(2) after the first batch of concrete mixture falls down, continuously pouring concrete, and controlling the buried depth of the conduit to be 2-6 m; in the pouring process, the height of the concrete surface in the detection hole is detected at any time, the embedding depth of the guide pipe is calculated, and the embedding depth is adjusted in time;

(3) in order to ensure the quality of the pile top, concrete with the height of 0.5-1.0 m is poured above the designed elevation of the pile top so as to ensure the strength of the concrete of the pile top, and the concrete is chiseled off before partial pile splicing so as to ensure that residual pile heads are not loose.

The invention relates to a glass fiber reinforcement and steel bar combined anti-floating pile and a construction method thereof, and the construction method has the advantages that:

(3) the GFRP reinforcements and the anchoring reinforcements are overlapped in a manner of respectively arranging a buckling piece at intervals up and down, so that the stability and reliability of the longitudinal reinforcement cage are ensured, and the reinforcement cage is prevented from generating overlarge deformation;

(4) according to the reinforcing cage positioning device, the pair of positioning reinforcing rings are arranged at the top of the reinforcing cage, and the cross bars are inserted into the positioning reinforcing rings, so that the reinforcing cage can be fixed at an accurate elevation, and the displacement and sinking of the reinforcing cage are prevented;

(5) because the GFRP rib belongs to the brittle material, the shearing resistance is very low, and is easy to be destroyed, if the GFRP rib is directly anchored in the bearing platform, then in the floating slurry removing process, the GFRP rib is easy to be destroyed, and the anti-floating pile and the bearing platform can not be tightly connected. Therefore, when the anti-floating pile is connected with the bearing platform, each GFRP rib at the top of the rib cage is connected with the bearing platform after being connected with one anchoring steel bar in a lap joint mode through the fastener in the range of 2m, corresponding anchoring steel bars and bearing platform tight connection are guaranteed even if the GFRP rib is damaged in the floating slurry removing process of the anti-floating pile top, and the problem that the GFRP rib cannot be tightly connected with the bearing platform due to the fact that the GFRP rib is easy to damage in the pile head chiseling-removing process is solved.

The rib cage structure and the material of the anti-floating pile and the connection with the bearing platform are different from common reinforced concrete anti-floating piles, the anti-floating pile mainly bears vertical tension, the rib cage is an important part of the anti-floating pile working together with concrete, and the construction quality of the rib cage structure directly influences the safety of the whole anti-floating pile foundation structure.

It should be noted that the above-mentioned embodiments are only for illustrating the technical concept and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. The utility model provides a combined anti-floating pile of glass fiber reinforcement and reinforcing bar, includes concrete pile body and arranges the inside muscle cage of concrete pile body in, its characterized in that: the reinforcement cage comprises a plurality of main reinforcements, GFRP spiral stirrups, annular reinforcing steel bars and anchoring steel bars; the central shafts of all the annular reinforcing steel bars are superposed on the same straight line extending along the longitudinal direction; the main reinforcements extend along the longitudinal direction and are uniformly distributed on the outer sides of the annular reinforcing steel bars; the GFRP spiral stirrup surrounds the outer side of the main reinforcement; the main reinforcement comprises a plurality of GFRP reinforcements and at least 3 reinforcements, and the GFRP reinforcements positioned at the top of the reinforcement cage are all anchored in the bearing platform through anchoring reinforcements.

2. The combined type anti-floating pile of glass fiber reinforced plastic and steel bars as claimed in claim 1, wherein: the part of the anchoring steel bar extending out of the bottom of the bearing platform is in lap joint with the upper end of the GFRP bar through at least two buckling pieces, and the length of the lap joint part is not less than 2 m.

3. The combined type anti-floating pile of glass fiber reinforced plastic and steel bars as claimed in claim 1, wherein: the upper and lower adjacent main ribs are overlapped through at least two buckling pieces, and the length of the overlapped part is not less than 44 times of the diameter of the main rib.

4. The combined type anti-floating pile of glass fiber reinforcement and steel reinforcement according to any one of claims 2 or 3, characterized in that: the fastener is a U-shaped bolt.

5. The combined type anti-floating pile of glass fiber reinforced plastic and steel bars as claimed in claim 1, wherein: and the GFRP bars and the annular reinforcing steel bars at the top of the reinforcement cage as well as the GFRP bars and the GFRP spiral stirrups are bound and fixed by non-galvanized steel wires.

6. The combined type anti-floating pile of glass fiber reinforced plastic and steel bars as claimed in claim 1, wherein: the steel bar cage also comprises a pair of positioning steel bar rings symmetrically arranged at the top of the steel bar cage, and a cross bar penetrating into the pair of positioning steel bar rings.

7. The combined type anti-floating pile of glass fiber reinforced plastic and steel bars as claimed in claim 1, wherein: the GFRP rib and the GFRP spiral stirrup are both made of alkali-free glass fibers with the alkali content of less than 0.8%; the resin matrix adopts any one or two mixed resins of vinyl resin and epoxy resin, and the raw material polymer of the resin matrix does not contain polyester component.

8. A construction method of a glass fiber reinforcement and steel bar combined anti-floating pile is characterized by comprising the following steps of:

9. The construction method of the glass fiber reinforcement and steel bar combined anti-floating pile according to claim 8, which is characterized by comprising the following steps:

s7, manufacturing a rib cage:

s8, placing a reinforcement cage:

s8.2, hanging the rib cage in alignment with the hole site;

10. The construction method of the glass fiber reinforcement and steel reinforcement combined type anti-floating pile according to claim 8, characterized in that: the step S7 of manufacturing the cage further includes symmetrically welding a pair of positioning reinforcing rings on the top of the cage, for inserting a cross bar into the positioning rings to fix the cage at the elevation.