1. A construction method of a bored pile foundation is characterized by comprising the following steps:

leveling the ground near the construction site, and determining the position of a pile point;

embedding pile casings around the pile points;

drilling the pile point position by using a drilling machine;

checking and cleaning holes drilled in the drill holes;

hoisting a reinforcement cage into the hole;

pouring concrete into the hole by using a guide pipe;

and dismantling the guide pipe, and carrying out nondestructive testing on the pile foundation.

2. The bored pile foundation construction method according to claim 1, wherein the pile casing is buried around the pile point position:

the slope of the protecting cylinder is less than 1%, and the diameter of the protecting cylinder is larger than that of the drill bit of the drilling machine and exceeds a preset value.

3. The method of constructing a bored pile foundation according to claim 1, wherein the step of performing a drilling operation on the pile point position using a drilling machine includes:

starting a slurry pump, and preparing slurry with a preset proportion;

landing a drill bit, starting the drill bit to rotate, and lifting the drill bit after the drill bit is filled with mud;

removing silt in the drill bit;

and closing the valve of the drill bit, rotating the drill bit back to the pile point position, and descending the drill bit to continue drilling.

4. The bored pile foundation construction method according to claim 1, wherein the step of inspecting and cleaning the hole drilled by the boring comprises:

manufacturing a hole detector by using a steel reinforcement cage, wherein the outer diameter of the hole detector is equal to the diameter of the hole, and the length of the hole detector is 4-6 times of the diameter of the hole;

when the deviation of the bent hole, the inclined hole or the shrinkage hole from the preset range is detected, re-drilling is needed;

and cleaning sediments in the holes.

5. The bored pile foundation construction method according to claim 1, wherein the step of hoisting a reinforcement cage into the hole includes:

adopting a section-by-section hoisting framework to be in place, horizontally hoisting the framework at two points, and hoisting the framework into the hole by an upper hoisting point after the framework is upright;

wherein, the length of each section of the reinforcement cage is 14-16 m, and the joint of the reinforcement cage adopts single-side lap welding.

6. The method of constructing a bored pile foundation according to claim 1, wherein said pouring concrete into said hole using a guide pipe comprises the steps of:

installing a guide pipe, so that the distance between the guide pipe and the bottom of the hole is within a first preset range;

and carrying out a water pressurizing test and a lifting test on the guide pipe.

7. The bored pile foundation construction method according to claim 6, wherein the first predetermined range is 30cm to 40 cm.

8. The bored pile foundation construction method according to claim 1, further comprising a manual bored pile before which a preventive measure is required, the preventive measure including:

the electric welding pipe is adopted to carry out well mouth protection at the hole digging position, and the brick building protection at the hole position is higher than the ground surface so as to prevent the hole from collapsing caused by the fact that the ground flows into the hole when meeting water.

9. The method of constructing a bored pile foundation according to claim 1, wherein said pouring concrete into said hole using a guide pipe further comprises the steps of:

determining the mixing proportion of the concrete to ensure that the concrete has good workability;

adding a high-efficiency retarding water reducer into concrete;

and detecting the thickness of the sediment, and if the thickness of the sediment exceeds the design requirement, cleaning the hole again.

10. The method for constructing the bored pile foundation according to claim 9, wherein after the step of adding the high efficiency retarding and water reducing agent into the concrete, the step of detecting the sediment thickness, and before the step of re-cleaning the hole if the sediment thickness exceeds the design requirement, the method further comprises:

pouring concrete into the hole, slowly pouring when the concrete in the guide pipe is not full, and keeping the bottom end of the guide pipe embedded 2-6 m below the concrete surface;

and observing whether the reinforcement cage floats upwards, and if so, taking a reinforcing measure for the reinforcement cage.

Background

In the building field, the cast-in-situ bored pile is the foundation of all buildings, the quality of the cast-in-situ bored pile directly influences the quality of the whole building, and the whole building can be inclined or even collapsed if the cast-in-situ bored pile is not manufactured. Therefore, the construction period and the quality of the cast-in-place pile in the building are strictly controlled. Then, the existing cast-in-situ bored pile construction method is complex and difficult, and causes a certain delay to the construction progress.

In view of the above, there is a need to provide a new method for constructing a bored pile foundation, which solves or at least alleviates the above technical drawbacks.

Disclosure of Invention

The invention provides a construction method of a bored pile foundation, and aims to solve the technical problems of complex construction method and high construction difficulty of the bored pile foundation in the prior art.

In order to achieve the above object, the present invention provides a bored pile foundation construction method, including:

leveling the ground near the construction site, and determining the position of a pile point;

embedding pile casings around the pile points;

drilling the pile point position by using a drilling machine;

checking and cleaning holes drilled in the drill holes;

hoisting a reinforcement cage into the hole;

pouring concrete into the hole by using a guide pipe;

and dismantling the guide pipe, and carrying out nondestructive testing on the pile foundation.

Optionally, the embedding of casing around the pile point position:

the slope of the protecting cylinder is less than 1%, and the diameter of the protecting cylinder is larger than that of the drill bit of the drilling machine and exceeds a preset value.

Optionally, the step of performing a drilling operation on the pile point position by using a drilling machine includes:

starting a slurry pump, and preparing slurry with a preset proportion;

landing a drill bit, starting the drill bit to rotate, and lifting the drill bit after the drill bit is filled with mud;

removing silt in the drill bit;

and closing the valve of the drill bit, rotating the drill bit back to the pile point position, and descending the drill bit to continue drilling.

Optionally, the step of inspecting and cleaning the hole drilled by the drill hole comprises:

manufacturing a hole detector by using a steel reinforcement cage, wherein the outer diameter of the hole detector is equal to the diameter of the hole, and the length of the hole detector is 4-6 times of the diameter of the hole;

when the deviation of the bent hole, the inclined hole or the shrinkage hole from the preset range is detected, re-drilling is needed;

and cleaning sediments in the holes.

Optionally, the step of hoisting the reinforcement cage into the hole includes:

adopting a section-by-section hoisting framework to be in place, horizontally hoisting the framework at two points, and hoisting the framework into the hole by an upper hoisting point after the framework is upright;

wherein, the length of each section of the reinforcement cage is 14-16 m, and the joint of the reinforcement cage adopts single-side lap welding.

Optionally, the step of pouring concrete into the hole by using the conduit comprises the following steps:

installing a guide pipe, so that the distance between the guide pipe and the bottom of the hole is within a first preset range;

and carrying out a water pressurizing test and a lifting test on the guide pipe.

Optionally, the first preset range is 30cm to 40 cm.

Optionally, the bored pile foundation construction method further includes a manual bored pile, and a safeguard measure is required before the manual bored pile, and the safeguard measure includes:

the electric welding pipe is adopted to carry out well mouth protection at the hole digging position, and the brick building protection at the hole position is higher than the ground surface so as to prevent the hole from collapsing caused by the fact that the ground flows into the hole when meeting water.

Optionally, the step of pouring concrete into the hole by using the guide pipe further comprises the following steps:

determining the mixing proportion of the concrete to ensure that the concrete has good workability;

adding a high-efficiency retarding water reducer into concrete;

and detecting the thickness of the sediment, and if the thickness of the sediment exceeds the design requirement, cleaning the hole again.

Optionally, after the step of adding the high efficiency retarding water reducing agent into the concrete, the step of detecting the sediment thickness, and before the step of clearing the hole again if the sediment thickness exceeds the design requirement, the method further includes:

pouring concrete into the hole, slowly pouring when the concrete in the guide pipe is not full, and keeping the bottom end of the guide pipe embedded 2-6 m below the concrete surface;

and observing whether the reinforcement cage floats upwards, and if so, taking a reinforcing measure for the reinforcement cage.

In the technical scheme of the invention, the construction method of the bored pile foundation comprises the steps of leveling the ground near a construction site and determining the position of a pile point; embedding pile casings around the pile points; drilling the pile point position by a drilling machine; checking and cleaning holes drilled in the drill holes; hoisting a reinforcement cage into the hole; pouring concrete into the hole by using a guide pipe; and (4) dismantling the guide pipe, and carrying out nondestructive testing on the pile foundation. The invention has the advantages of simple construction scheme and small construction difficulty.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic flow chart of a method for constructing a bored pile foundation according to a first embodiment of the present invention;

FIG. 2 is a schematic flow chart of a bored concrete pile foundation construction method according to a second embodiment of the present invention;

FIG. 3 is a schematic flow chart of a bored concrete pile foundation construction method according to a third embodiment of the present invention;

FIG. 4 is a schematic flow chart illustrating a method for constructing a bored pile foundation according to a fourth embodiment of the present invention;

fig. 5 is a schematic flow chart of a bored pile foundation construction method according to a fifth embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that all the directional indicators (such as the upper and lower … …) in the embodiment of the present invention are only used to explain the relative position relationship, movement, etc. of the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

Moreover, the technical solutions in the embodiments of the present invention may be combined with each other, but it is necessary to be able to be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent, and is not within the protection scope of the present invention.

Referring to fig. 1, according to a first embodiment of the present invention, there is provided a bored pile foundation construction method including:

s100, leveling the ground near a construction site, and determining the position of a pile point;

s200, embedding a pile casing around the pile point;

s300, drilling the pile point position by using a drilling machine;

s400, checking and cleaning holes drilled in the drill holes;

s500, hoisting the reinforcement cage into the hole;

s600, pouring concrete into the hole by using a guide pipe;

s700, removing the guide pipe, and carrying out nondestructive testing on the pile foundation.

In the above embodiment, the pile foundation is drilled piles of phi 125 and phi 150cm, the drilling machine is used for model selection according to the conditions of pile foundation distribution, field geological conditions, designed pile diameter, pile length and the like, and rotary drilling and manual hole digging are adopted to form holes. Before the construction of the drilled pile, the drilled site is cleaned, an excavator is adopted to level the walking access way of the drilling machine, and the excavator is used to level the original surface. After accurately discharging a cross control pile of the drilling pile, performing pile casing embedding work, after pile casing and locking construction is completed, guiding a leveling point elevation to the top surfaces of the pile casing and the locking, and marking by red paint, wherein the top surface is 30cm higher than the ground during pile casing and locking construction. And (3) constructing a settling pond between each pier and each platform and near the center line of the line, wherein the settling circulation pond is arranged on the principle that the mud slag settling capacity can meet the drilling requirement and the environment is protected. And finishing the checking and correcting of the size of the drill bit. The bottom of the drilling machine should be flatly padded and kept stable so as not to generate deviation and sinking, and the bottom of the drilling machine should pass through a plumb line of an upper sliding wheel rim of the drilling frame. And then, after the hole is inspected and cleaned, hoisting a reinforcement cage into the hole, pouring concrete into the hole by using the guide pipe to manufacture a cast-in-place pile, dismantling the guide pipe and carrying out nondestructive testing on the pile foundation. The embodiment has the advantages of simple construction scheme and low construction difficulty.

Further, in burying pile casing around the pile point position:

the slope of the protecting cylinder is less than 1%, and the diameter of the protecting cylinder is larger than the diameter of the drill bit of the drilling machine and exceeds a preset value. Specifically, the diameter of the casing is larger than the diameter size of the drill bit by 40 cm; the position deviation of the top surface of the pile casing is required to be not more than 5cm, and the inclination of the pile casing is required to be not more than 1%.

Referring to fig. 2, according to the second embodiment of the present invention, the step of performing a drilling operation for a pile point position using a drilling machine includes:

s301, starting a slurry pump, and preparing slurry with a preset proportion;

s302, landing the drill bit, starting the drill bit to rotate, and lifting the drill bit after the drill bit is filled with mud;

s303, removing silt in the drill bit;

s304, closing the valve of the drill bit, rotating the drill bit back to the pile point position, and descending the drill bit to continue drilling.

Specifically, the drilling process includes several small steps:

1) before drilling, whether various machines and tools are in good state and whether slurry preparation is sufficient is checked. And (4) whether the hydroelectric pipeline is smooth or not so as to ensure the normal operation.

2) Before formal drilling, a slurry pump is started to prepare proper slurry.

3) The drill bit lands on the ground, the drill bit is rotated to start drilling, the drill bit is pressurized and drilled by the dead weight of the drill bit, the drill bit is rotated and extruded, the drill bit is lifted after the drill bit is filled with slurry, and the slurry is timely supplemented and a water head is kept in the lifting process of the drill bit.

And (5) unloading the mud and sand in the drill bit after the drill bit is lifted out. And closing the valve of the drill bit, rotating the drill bit back to the drilling place, fixing the upper end of the rotating body, and descending the drill bit to continue drilling.

4) And after drilling is finished, cleaning the hole for the first time and removing sediments at the bottom of the hole.

5) The drilling operation is continuously carried out without interruption. For stopping drilling, a protective cover is added on the hole opening, and the drill bit is lifted out of the hole channel to prevent burying drilling, and simultaneously, the height of the mud surface in the hole and the specific gravity and viscosity of the mud are kept to meet the requirements.

6) Before drilling, drawing a geological section diagram at a hole position, hanging the geological section diagram on a drill floor, and using the geological section diagram as a reference for selecting proper drill bits, bit pressure, drilling speed and mud proportion for different soil layers. And often paying attention to soil layer changes, fishing slag samples at the soil layer changes to identify the soil layers, checking the slag samples with the designed stratum in a recording table, and filling a drilling recording table in the drilling process.

7) In the drilling process, the loss and the leaked slurry are timely supplemented to be 1.0 to 1.5m higher than the water level outside the hole or the underground water level; the slurry concentration in the drilled hole is ensured, and quality accidents such as hole collapse and hole shrinkage are prevented.

8) After the drilling is finished, the hole condition is checked by using a hole checking device, so that accidents such as hole bending and the like are prevented, and the verticality of the pile foundation is ensured to meet the requirement.

9) When the distance between the drill hole and the designed elevation is 1 m, the drilling speed and the depth are controlled, the excessive drilling is prevented, and geological data are verified to judge whether the drill hole enters the designed bearing stratum or not.

10) And when the drilling depth meets the design requirement, checking the hole depth, the hole diameter and the hole shape.

Referring to fig. 3, according to a third embodiment of the present invention, the step of inspecting and cleaning the hole drilled by drilling comprises:

s401, manufacturing a hole detector by using a steel reinforcement cage, wherein the outer diameter of the hole detector is equal to the diameter of the hole, and the length of the hole detector is equal to 4-6 times of the diameter of the hole;

s402, when the deviation of the bent hole, the inclined hole or the shrinkage hole from a preset range is detected, re-drilling is needed;

and S403, cleaning sediments in the holes.

After the depth of the pile reaches the design requirement, the indexes of the pile diameter, the verticality and the like must be checked and well recorded. The diameter and the verticality of the pile are checked by a hole checking device which is made of a steel reinforcement cage, the outer diameter of the hole checking device is equal to the designed hole diameter, and the length of the hole checking device is equal to 4-6 times of the hole diameter. And if the conditions of hole bending, inclined hole, hole shrinkage and the like are serious, re-drilling is needed. The ballast thickness must be controlled within specification or design requirements. And after the steel bar is qualified, the steel bar cage is started to be put.

Further, the step of hanging the reinforcement cage into the hole comprises:

adopting a section-by-section hoisting framework to be in place, horizontally hoisting the framework at two points, and hoisting the framework into the hole by an upper hoisting point after the framework is upright;

wherein, the length of each section of the reinforcement cage is 14-16 m, and the joint of the reinforcement cage adopts single-side lap welding.

Specifically, the steel reinforcement cage is manufactured according to design drawings and construction specification requirements, the ears are symmetrically welded around the steel reinforcement cage to serve as pile foundation protective layers, the positioning of the steel reinforcement cage is guaranteed, enough protective layers are arranged, and at least 4 lengthened steel bars are welded on the top section of the steel reinforcement cage to fix the steel reinforcement cage. The binding and welding process of the reinforcement cage is strictly executed according to design requirements and construction specifications in construction.

After the reinforcement cage is manufactured, the reinforcement cage is transported to the site, and the reinforcement cage can be timely lifted by the drill frame and can also be placed by a crane for a drilling machine. In order to ensure the quality of the formed hole, the time of placing the steel reinforcement cage must be shortened, the length of the steel reinforcement cage is increased as much as possible, the longer steel reinforcement cage is manufactured in sections, each section is about 15m long, and a joint of the steel reinforcement cage adopts single-side lap welding (10 Dd). In order to prevent the reinforcement cage from being placed eccentrically and ensure the thickness of a concrete protective layer, a group of positioning reinforcements is arranged every 2 m. When the steel reinforcement cage is hoisted, the framework is hoisted in place section by section according to the serial number of the hanging plate. Two points are horizontally lifted, and the framework is lifted into the hole by the upper lifting point after being erected.

Referring to fig. 4, according to a fourth embodiment of the present invention, the pouring of concrete into the hole using the guide tube comprises the steps of:

s601, installing a guide pipe to enable the distance between the guide pipe and the bottom of the hole to be within a first preset range;

and S602, performing a water pressurizing test and a lifting test on the guide pipe.

The first preset range is 30 cm-40 cm.

The concrete pouring adopts a lower conduit to pour underwater, and the pouring conduit adopts a rapid bayonet vertical lifting conduit with the diameter not less than 250 mm. The guide pipe is assembled before being used, the length is required by pre-splicing according to the hole depth, the distance between the bottom and the hole bottom is 30-40 cm, the guide pipe has enough rigidity and strength, a water pressing test is carried out before and after the guide pipe is used for a period of time, and whether the water-insulation plug can pass smoothly is tested. The water pressure in the watertight test is not less than 1.3 times of the pressure of the depth of water in the hole; the water pressure test is determined according to the maximum pressure which may occur during construction. The guide pipes are provided with scales and numbers from bottom to top, and a lifting test is carried out before filling.

Further, the construction method of the bored pile foundation further comprises the steps of manually digging a hole pile, wherein protective measures are required before the manually digging the hole pile, and the protective measures comprise the following steps:

the electric welding pipe is adopted to carry out well mouth protection at the hole digging position, and the brick building protection at the hole position is higher than the ground surface so as to prevent the hole from collapsing caused by the fact that the ground flows into the hole when meeting water.

And in the construction process of the manual hole digging pile, well mouth protection is carried out by using electric welding pipes, and the hole opening part is protected by brick masonry and is 30cm higher than the ground surface so as to prevent the ground rainwater from flowing into the hole to cause hole collapse. When the manual hole digging pile is excavated and constructed, a worker can go in and out the hole digging pile by using the crawling ladder to operate, the crawling ladder is firmly fixed with the hole wall, meanwhile, in order to prevent the collapse of the hole wall, the quality inspection of the wall protection of the hole wall is enhanced, the concrete of the wall protection and the concrete of the pile foundation have the same grade, the concrete is intensively mixed, and the unqualified wall protection is constructed again. Various effective protective measures are taken in the construction operation, measures such as ventilation, illumination, dust prevention, water prevention, temperature reduction, harmful gas prevention and the like are taken, the environmental sanitation is protected, the labor protection is enhanced, labor protection articles and tools are distributed and used according to the regulations, and the health and the production safety of constructors are ensured.

For problems possibly occurring in construction, the countermeasures comprise the following steps:

water leakage treatment

Because the bored concrete pile closes on the riverbed, and the hole depth is more than 20m moreover, the excavation in-process, the phenomenon that the seepage water yield is bigger than normal has probably appeared in pile foundation upper portion gravel layer, and my department combines the scene reality, takes following treatment:

i, strong drainage, and a water pump with high drainage capacity is adopted.

And II, plugging, namely plugging a water leakage channel by adopting cement and water glass on the premise of forced drainage, so that the water leakage amount is reduced.

And III, when the retaining wall concrete is poured, the cement dosage and the mixing amount of the accelerator are properly increased, and the early strength of the concrete is improved. Drain holes are randomly arranged to reduce the side pressure.

Second, collapse caused by loose structure

Because the pile foundation area is basically positioned at the riverbed part, holes are not easy to form, and the hole wall is loose and easy to collapse, aiming at the situation, the following measures are adopted for processing and controlling:

and I, shortening the depth of the retaining wall and accelerating the frequency of support.

And II, adopting a temporary wood plate support or reinforcing steel bar net piece support measure at the periphery of the boundary of the retaining wall, and increasing the construction safety factor.

Referring to fig. 5, according to the fifth embodiment of the present invention, the pouring of concrete into the hole using the guide tube further comprises the steps of:

s6001, determining the mixing proportion of the concrete to ensure that the concrete has good workability;

s6002, adding a high-efficiency retarding water reducing agent into concrete;

s6003, detecting the thickness of the sediments, and if the thickness of the sediments exceeds the design requirement, cleaning the holes again.

And (3) pouring concrete in time, and if the time is too long, sediment needs to be measured again, and the sediment thickness exceeds the design requirement and needs to be cleaned again. The concrete must have good workability and the mix ratio should be determined by testing. In order to prevent serious accidents caused by the long time of the underwater concrete in the pouring process and the concrete solidification, the concrete can be doped with the high-efficiency slow-setting water reducing agent to delay the solidification time, improve the workability of the concrete and save the cement. And (5) intensively stirring the concrete, and pumping and pouring.

Further, after the step of adding the high-efficiency retarding water reducing agent into the concrete, the sediment thickness is detected, and before the step of clearing the holes again if the sediment thickness exceeds the design requirement, the method further comprises the following steps:

pouring concrete into the hole, slowly pouring when the concrete in the guide pipe is not full, and keeping the bottom end of the guide pipe embedded 2-6 m below the concrete surface;

and observing whether the reinforcement cage floats upwards, and if so, taking a reinforcing measure for the reinforcement cage.

The method comprises the steps of accurately calculating the volume of first-tray concrete before first-batch concrete pouring, manufacturing a funnel meeting the volume of bottom-sealing concrete, ensuring that the bottom sealing is smooth, and carrying out normal pouring after the success of the bottom sealing is confirmed. The pouring process is strictly carried out according to the standard, and various detections such as concrete quality, conduit embedding depth and the like are carried out at any time so as to ensure the smoothness of the whole pouring process.

When the concrete in the conduit is not full, the casting is performed slowly to prevent the high-pressure air bag from being formed in the conduit and the conduit from being pressed and leaked. The bottom end of the guide pipe is buried 2-6 m below the concrete surface all the time, and the guide pipe is strictly forbidden to be lifted out of the concrete surface.

And in the concrete pouring process, observing whether the reinforcement cage floats upwards, or else, taking a reinforcing measure.

Towards the end of the pour, the height of the concrete column in the conduit is relatively reduced, the concrete pressure in the conduit is reduced, and the mud consistency of the borehole outside the conduit is increased and the specific gravity is increased. If the concrete is difficult to lift, water can be added into the holes to dilute the slurry, so that the specific gravity of the slurry is reduced, and the pouring work is smoothly carried out.

After the pouring is finished, the elevation of the concrete surface of the pile top is accurately measured by using the measuring rope, and the excess pouring allowance is considered according to the standard requirement.

Secondly, still include to reinforcing bar cage come-up precaution and treatment process:

firstly, when the drilling depth reaches the designed elevation, the rotation of the drilling machine is not stopped immediately, but idling (the drilling rod is hung, the hole depth is not increased) is carried out for a period of time, the mud in the mud pit and the mud in the hole are circulated uninterruptedly during the period, and the mud in the mud pit cannot be too thin, the density is not less than 1.2, and the construction of the next procedure, namely the drilling rod pulling and the installation of a conduit for pouring underwater concrete can be carried out until the mud is uniformly adjusted and the mud blocks are crushed.

Secondly, the requirements of concrete are as follows: controlling the concrete slump of the underwater poured pile foundation to be 18-22 cm; the concrete for pouring the pile foundation is required to have good workability and fluidity, so that the concrete can be well 'slushy' in the pouring process.

When pouring underwater concrete, when concrete touches the reinforcing bar, will pour the speed of concrete and suitably slow down, treat that the concrete of pouring highly exceeds reinforcing bar cage bottom surface 1 ~ 2 meters time, the pouring speed of concrete is quickened again, and at this moment the concrete in the stake has wrapped up reinforcing bar cage, and reinforcing bar cage will not come up again.

Fourthly, welding barbs on the main reinforcement of the reinforcement cage to prevent the reinforcement cage from floating upwards. 3 ~ 4 "barbs" are welded to the same cross-section of steel reinforcement cage, and every cage establishes twice.

The upper end of the reinforcement cage is fixed on the protective cylinder through a hanging rib, can bear part of jacking force, and has the function of preventing the reinforcement cage from rising.

Sixthly, the reinforcement cage is not far away from the wellhead, and is prevented by sleeving a plurality of steel pipes on the reinforcement stirrup at the top end and then fixing the reinforcement stirrup on a retaining cylinder and other fixtures by an S hook.

And seventhly, floating cage treatment measures:

a. when the pile foundation concrete is poured, the change condition of the hanging ribs for hanging the steel bar cage is observed, if the hanging ribs are upwards gun, the steel bar cage is already floated, at the moment, measures are taken immediately, namely, the pouring speed of the concrete is slowed down, the guide pipe is repeatedly lifted slowly and falls quickly by a crane on a drilling machine, namely, the floated steel bar cage is brought back to the poured concrete slowly, the buried depth of the guide pipe and the level of the poured concrete are accurately calculated, and the concrete pouring elevation and the buried depth of the guide pipe are mastered at any time. The guide pipe can not be pulled out of the concrete surface due to the floating cage problem, so that the pile is broken.

b. If the reinforcement cage still can not descend, only can pull out the cage and heavily bore the processing.

Although the embodiment of the present invention has been shown and described, the scope of the present invention is not limited thereto, it should be understood that the above embodiment is illustrative and not to be construed as limiting the present invention, and that those skilled in the art can make changes, modifications and substitutions to the above embodiment within the scope of the present invention, and that these changes, modifications and substitutions should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

In the present invention, the terms "first", "second", "third", "fourth" and "fifth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, and those skilled in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.