CN114673141A - Sand layer geological pile foundation hole bottom grouting device and construction method - Google Patents

Abstract

A sand bed geological pile foundation hole bottom grouting device and a construction method thereof are disclosed, wherein the device comprises: the steel reinforcement cage, a plurality of water pockets, a plurality of fixed guiding mechanism, a plurality of water injection ooff valve. The arrangement directions of the water bags are consistent with that of the reinforcement cage by installing a plurality of fixed guide mechanisms in the reinforcement cage; injecting water into the water bags through the water injection switch valves, and smearing engine oil on the surfaces of the water bags after the water injection is finished so as to be convenient for subsequent demoulding and taking out; installing the reinforcement cage with the plurality of water bags to the drilled pile hole, and performing concrete pouring on the pile foundation; after the pile foundation concrete reaches the design age, taking out the pile foundation concrete after water is discharged from the water bags to form a plurality of pore channels; and finally, grouting is completed for the plurality of pore channels. Compared with the traditional construction method of the grouting pipe through the embedded steel pipe, the embodiment of the invention recycles the water bag, saves steel, avoids the quality problem caused by the fact that grouting cannot be carried out due to blockage of the grouting pipe, and also accelerates the construction progress.

Description

Sand layer geological pile foundation hole bottom grouting device and construction method

Technical Field

The invention relates to the field of building construction, in particular to a sand layer geological pile foundation hole bottom grouting device and a construction method.

Background

The pile foundation is the main means and form of the deep foundation of the building, and the cast-in-situ bored pile can be made into a large-size pile to be drilled into a deep soil layer, can provide large bearing capacity and the like, and is widely applied to the field of the building foundation. Because of the inherent defects of the hole forming process of the bored pile foundation, particularly in coastal beach sand layer geology, the thickness of the sediment at the bottom of the pile after hole forming can not meet the design and standard requirements, therefore, the foundation treatment grouting technology is introduced into the pile foundation in China, and the measure of implementing pressure grouting on the pile end, namely the pile foundation post-grouting technology, is adopted. The post-grouting technology for pile foundation is characterized by that after the pile is formed, a pre-buried grouting device is used, after the pile body has reached a certain strength, the high-pressure grouting pump is used to inject cement paste, and the hole bottom sediment is solidified, so that the inherent defects of traditional process can be eliminated, and the bearing capacity of the pile can be raised.

The conventional post-grouting technology for the pile foundation is a pre-embedded seamless steel pipe, and after the pile body concrete reaches a certain strength, hole bottom grouting is carried out through the pre-embedded steel pipe. However, in the actual construction process, when the pile foundation is subjected to underwater concrete pouring, a large amount of concrete cement paste often enters the embedded seamless steel pipe to block the steel pipe, so that grouting can not be performed through the embedded steel pipe in the later period, and the sediment at the bottom of the hole can not be cured to influence the quality of the pile foundation, so that the bearing capacity of the pile foundation cannot meet the design requirements, the installation and operation are difficult, the embedded steel pipe has the defects of high cost, long construction period and the like.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a hole bottom grouting device for a sand layer geological pile foundation, which solves the problems that the technical quality requirement of the existing pile foundation post-grouting technology of pre-embedded seamless steel pipes is difficult to reach the standard and the installation and operation are difficult.

The invention further provides a sand layer geological pile foundation hole bottom grouting construction method.

According to the embodiment of the first aspect of the invention, the sand layer geological pile foundation hole bottom grouting device comprises:

a reinforcement cage;

each water bag comprises a water storage part and a water injection part, the water storage part is arranged along the axial direction of the reinforcement cage, and the water injection part is positioned at the top of the water bag;

the fixed guide mechanisms are arranged on the inner side of the reinforcement cage and connected with main reinforcements of the reinforcement cage, and are used for limiting the positions of the water bags in the reinforcement cage;

and the water injection switch valves are connected with the water injection parts in a one-to-one correspondence manner.

The sand layer geological pile foundation hole bottom grouting device provided by the embodiment of the invention at least has the following technical effects: the arrangement directions of the water bags are consistent with that of the reinforcement cage by installing a plurality of fixed guide mechanisms in the reinforcement cage; injecting water into the water bags through the water injection switch valves by using high-pressure water injection equipment, and smearing engine oil on the surfaces of the water bags after water injection is finished so as to demold and take out the water bags subsequently; installing the reinforcement cage with the plurality of water bags to the drilled pile hole, and performing concrete pouring on the pile foundation; when the pile foundation concrete reaches the design age, taking out the pile foundation concrete after water is discharged from the water bags through the water injection switch valves to form a plurality of pore channels; and finally, grouting is completed for the plurality of pore passages. Compared with the traditional construction method of the grouting pipe through the embedded steel pipe, the embodiment of the invention recycles the water bag, saves steel, avoids the quality problem caused by the fact that grouting cannot be carried out due to blockage of the grouting pipe, and also accelerates the construction progress.

According to some embodiments of the present invention, the plurality of fixed guide mechanisms are uniformly divided into a plurality of fixed guide units, the plurality of fixed guide units are arranged at intervals in the vertical direction inside the reinforcement cage, and each of the fixed guide mechanisms in each of the fixed guide units is located on the same horizontal plane and is arranged in a ring shape at equal intervals.

According to some embodiments of the present invention, the plurality of fixed guide mechanisms are a plurality of 30mm inner diameter iron rings, each of the iron rings is made of a steel bar with an inner diameter of 6mm, and the plurality of iron rings are welded to the plurality of main bars.

According to some embodiments of the invention, the plurality of water pockets are a plurality of cylinders with a diameter of 20 mm.

According to some embodiments of the invention, each of the water bags is of a polyurethane polymer film structure.

According to some embodiments of the invention, the interior of each of the water bladders is subjected to a water injection pressure that is greater than a concrete pouring pressure.

According to some embodiments of the present invention, the water injection switching valves are respectively disposed at top ends of the water injection parts.

According to the embodiment of the second aspect of the invention, the sand layer geological pile foundation hole bottom grouting construction method comprises the following steps:

excavating a reservoir and a sedimentation tank;

measuring and lofting the pile foundation and embedding a steel casing;

drilling a stratum, and installing the sand layer geological pile foundation hole bottom grouting device in any embodiment of the first aspect of the invention into a drilled pile hole;

carrying out concrete pouring on the pile foundation;

and grouting the bottom of the hole.

The sand layer geological pile foundation hole bottom grouting construction method provided by the embodiment of the invention at least has the following technical effects: a drainage system is formed by excavating the reservoir and the sedimentation tank, so that the cyclic utilization of water resources is ensured; the hole piles are protected by embedding the steel pile casings, so that hole collapse is prevented, and the construction progress and the construction safety are prevented from being influenced; the sand layer geological pile foundation hole bottom grouting device is installed to a drilled pile hole, and concrete pouring is carried out on a pile foundation; when the pile foundation concrete reaches the design age, taking out the pile foundation concrete after water is discharged from the water bags through the water injection switch valves to form a plurality of pore channels; and finally, grouting a plurality of pore channels. Compared with the traditional construction method of the grouting pipe through the embedded steel pipe, the embodiment of the invention recycles the water bag, saves steel, avoids the quality problem caused by the fact that grouting cannot be carried out due to blockage of the grouting pipe, and also accelerates the construction progress.

According to some embodiments of the invention, the sand layer geological pile foundation hole bottom grouting device is obtained by the following steps:

manufacturing a reinforcement cage, wherein the reinforcement cage is composed of a plurality of main reinforcements and a plurality of stirrups;

manufacturing a plurality of iron rings with the inner diameter of 30mm, wherein each iron ring is composed of a plurality of steel bars with the inner diameter of 6mm, and the plurality of iron rings are welded on the plurality of main bars on the inner side of the steel bar cage;

selecting a water bag, wherein the water bag is a cylinder with the diameter of 20mm and is made of a polyurethane polymer film structure;

injecting water into the water bags by using an external high-pressure water injection device through a plurality of water injection switch valves until water storage parts of the water bags are full of water, and stopping injecting the water;

and coating engine oil on the outer surfaces of the water bags, and placing the water bags in the iron rings.

According to some embodiments of the invention, the grouting of the bottom of the hole comprises the steps of:

discharging the water in the water bags through the water injection switch valves;

taking out a plurality of water bags from the sand layer geological pile foundation hole bottom grouting device;

cleaning a plurality of pore passages formed by the pile foundation after the water bags are taken out;

and performing hole bottom grouting on the plurality of the pore channels.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural diagram of a sand bed geological pile foundation hole bottom grouting device in an embodiment of the invention;

FIG. 2 is a schematic structural view of a water bladder and a water injection on-off valve according to an embodiment of the present invention;

FIG. 3 is a top view of the reinforcement cage, water bladder and stationary guide mechanism of an embodiment of the present invention;

FIG. 4 is a flow chart of a sand layer geological pile foundation hole bottom grouting construction method according to the embodiment of the invention.

Reference numerals:

a reinforcement cage 100, a main reinforcement 110, a stirrup 120,

A water bag 200, a water storage part 210, a water injection part 220,

A fixed guide mechanism 300,

A water injection on-off valve 400.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality means two or more. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly defined, terms such as set, mounted, connected, disconnected and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the terms in the present invention in combination with the specific contents of the technical solutions.

A sand layer geological pile foundation hole bottom grouting device according to an embodiment of the first aspect of the invention is described below with reference to fig. 1 to 4.

The sand bed geological pile foundation hole bottom grouting device of the embodiment of the invention comprises:

a reinforcement cage 100;

the water storage part 210 is arranged along the axial direction of the reinforcement cage 100, and the water injection part 220 is positioned at the top of the water bag 200;

the plurality of fixed guide mechanisms 300 are all arranged on the inner side of the reinforcement cage 100 and are connected with the main reinforcements 110 of the reinforcement cage 100, and the plurality of fixed guide mechanisms 300 are used for limiting the positions of the plurality of water bags 200 in the reinforcement cage 100;

and a plurality of water injection switching valves 400 connected to the plurality of water injection parts 220 in a one-to-one correspondence.

Referring to fig. 1 to 3, the reinforcement cage 100 is a long cylinder in appearance, a plurality of parallel main reinforcements 110 form a cylinder ring, and a plurality of stirrups 120 are wound around the cylinder ring formed by the plurality of main reinforcements 110, so as to form the reinforcement cage 100 with a stable structure; the upper end portion of the main reinforcement 110 is a bent portion, which is exposed above the ground surface when the reinforcement cage 100 is used; the plurality of fixed guide mechanisms 300 are uniformly distributed on the plurality of main ribs 110 so as to ensure that the plurality of water bags 200 are arranged in the vertical direction and consistent with the arrangement direction of the reinforcement cage 100; when the hole bottom grouting device for the sand layer geological pile foundation is used, the main body of the reinforcement cage 100 and the water storage parts 210 of the plurality of water bags 200 are below the ground surface of the sand layer geology, and the bending parts of the reinforcement cage 100 and the water injection parts 220 of the plurality of water bags 200 are above the ground surface of the sand layer geology, so that constructors can conveniently place or take out the reinforcement cage 100 and the water bags 200 and the like for related operations; each water filling switching valve 400 is provided at the water filling part 220 of each water bladder 200 to facilitate the construction worker to fill and drain the water bladder 200.

Specifically, the construction method utilizing the sand bed geological pile foundation hole bottom grouting device provided by the embodiment of the invention specifically comprises the following steps: the sand bed geology of the underground is drilled, the sand bed geology pile foundation hole bottom grouting device is installed to a drilled pile hole, water can be injected into the water bags 200 through the water injection switch valves 400 no matter before the device is installed to the pile hole or after the device is installed to the pile hole, and meanwhile engine oil needs to be smeared on the surfaces of the water bags 200 in advance before the water bags 200 are placed on the reinforcement cage 100. And when the concrete of the pile foundation reaches the design age, namely after the concrete is solidified, draining the water bags 200 and taking out the water bags from the device to form a plurality of pore channels, and finally grouting the pore channels to finish the construction.

According to the hole bottom grouting device for the sand layer geological pile foundation, the plurality of fixed guide mechanisms 300 are arranged in the reinforcement cage 100, so that the arrangement directions of the plurality of water bags 200 are consistent with that of the reinforcement cage 100; injecting water into the water bags 200 through the water injection switch valves 400 by using high-pressure water injection equipment, and smearing engine oil on the surfaces of the water bags 200 after water injection is finished so as to demold and take out the water bags 200; installing the reinforcement cage 100 in which the plurality of water bags 200 are placed to the drilled pile hole, and performing concrete pouring on the pile foundation; when the pile foundation concrete reaches the design age, taking out the water bags 200 after water is discharged from the water injection switch valves 400 to form a plurality of pore channels; and finally, grouting is completed for the plurality of pore passages. Compared with the traditional construction method of the grouting pipe through the embedded steel pipe, the embodiment of the invention recycles the water bag 200, saves steel, avoids the quality problem caused by the fact that grouting cannot be carried out due to blockage of the grouting pipe, and also accelerates the construction progress.

In some embodiments of the present invention, the plurality of fixed guide mechanisms 300 are uniformly grouped into a plurality of fixed guide units in number, the plurality of fixed guide units are disposed at intervals in the vertical direction inside the reinforcement cage 100, and each fixed guide mechanism 300 in each fixed guide unit is located at the same horizontal plane and is disposed in a ring shape at equal intervals.

Referring to fig. 3, in a top view, for example, one fixed guiding unit inside the reinforcement cage 100 is composed of two fixed guiding mechanisms 300 (in some embodiments, one fixed guiding unit may be composed of more fixed guiding mechanisms 300), and the two fixed guiding mechanisms 300 are annular and symmetrically arranged in appearance. Referring to fig. 1, a plurality of fixed guide units are disposed at intervals in a vertical direction in which the reinforcement cage 100 is disposed, and the fixed guide mechanism 300 in each fixed guide unit is in the same plane. Therefore, the plurality of fixing guide mechanisms 300 are regularly disposed at the inner side of the reinforcement cage 100 to ensure the stability of the fixing guide function of the plurality of water pockets 200.

In some embodiments of the present invention, the plurality of fixed guide mechanisms 300 are a plurality of 30mm inner diameter iron rings, each made of a steel bar having an inner diameter of 6mm, and the plurality of iron rings are welded to the plurality of main bars 110.

Specifically, the fixing guide mechanism 300 can be ensured to have a good fixing effect by using an iron ring. In some embodiments, the fixed guide 300 may also be made of alloy, stainless steel, composite materials; meanwhile, the fixing guide mechanism 300 can be adjusted to be an annular buckle on the annular basis, so that the water bag 200 can be placed in the reinforcement cage 100 conveniently.

In some embodiments of the present invention, the plurality of water pockets 200 are a plurality of cylinders having a diameter of 20 mm.

Specifically, referring to fig. 2, the water bladder 200 is shaped after water is injected, and can maintain the appearance of a cylinder, but due to the difference in material, when the water bladder 200 is not injected with water, if the water bladder 200 is made of a material with relatively stronger hardness, the water bladder 200 itself can maintain the shape of a cylinder; if the water bladder 200 is made of a relatively less rigid material, it may be difficult for the water bladder 200 to present a distinct cylindrical shape in appearance.

In some embodiments of the present invention, each water bladder 200 is formed of a polyurethane polymer film.

Specifically, the polyurethane polymer film structure has the advantages of thermoplasticity, high strength, large elongation, good rebound resilience, wear resistance, oil resistance, aging resistance, low temperature resistance and the like, so that the requirements of the water bag 200 on relevant indexes to be met in the construction process are met.

In some embodiments of the present invention, the interior of each water bladder 200 is subjected to a water injection pressure that is greater than the concrete pouring pressure.

Specifically, the conventional method is to form the hole by using a seamless steel pipe, and the hardness of the seamless steel pipe is obviously stronger than that of the concrete structure, so that the formation of the hole can be ensured. Similarly, for the water bag 200 used in the embodiment of the present invention, the hardness after water injection should be stronger than that of the concrete structure, and specifically, the water injection pressure inside the water bag 200 should be higher than the concrete pouring pressure to ensure the formation of the pore channel.

In some embodiments of the present invention, a plurality of water injection switching valves 400 are respectively disposed at the top ends of the plurality of water injection parts 220.

Specifically, referring to fig. 2, the water filling on-off valve 400 is disposed at the top end of the water filling part 220 of the water bladder 200, which is more suitable for the operation flow implementation of the construction personnel. In some embodiments, the water filling switching valve 400 may also be disposed at a side of the water filling part 220.

According to the second aspect of the invention, the sand layer geological pile foundation hole bottom grouting construction method comprises the following steps:

excavating a reservoir and a sedimentation tank;

measuring and lofting the pile foundation and embedding a steel casing;

drilling a stratum, and installing a sand layer geological pile foundation hole bottom grouting device in any one embodiment of the first aspect of the invention into a drilled pile hole;

carrying out concrete pouring on the pile foundation;

and grouting the bottom of the hole.

Specifically, referring to fig. 1 to 4, sites are arranged as required to make construction preparations, and a sedimentation tank and a reservoir are excavated to make a drainage system and ensure recycling of water resources; measuring a pile foundation, lofting a pile position, and burying a steel casing around the pile position; drilling a stratum where the sand layer geology is located, and after drilling is completed, placing the sand layer geological pile foundation hole bottom grouting device in the embodiment of the invention into a pile hole (before the device is placed, water can be injected into the water bag 200 and placed into the reinforcement cage 100, or after the device is placed, water can be injected into the water bag 200 and placed into the reinforcement cage 100); and then, pouring concrete, and taking out the sand layer geological pile foundation hole bottom grouting device to complete hole bottom grouting after the concrete solidification strength meets the design standard.

According to the sand bed geological pile foundation hole bottom grouting construction method, the water storage tank and the sedimentation tank are excavated to form a drainage system, so that the cyclic utilization of water resources is ensured; the hole piles are protected by embedding the steel pile casings, so that hole collapse is prevented, and the construction progress and the construction safety are prevented from being influenced; the sand layer geological pile foundation hole bottom grouting device is installed to a drilled pile hole, and concrete pouring is carried out on a pile foundation; when the pile foundation concrete reaches the design age, taking out the water bags 200 after water is discharged from the water injection switch valves 400 to form a plurality of pore channels; and finally, grouting a plurality of pore channels. Compared with the traditional construction method of the grouting pipe through the embedded steel pipe, the embodiment of the invention recycles the water bag 200, saves steel, avoids the quality problem caused by the fact that grouting cannot be carried out due to blockage of the grouting pipe, and also accelerates the construction progress.

In some embodiments of the invention, the sand layer geological pile foundation hole bottom grouting device is obtained by the following steps:

manufacturing a reinforcement cage 100, wherein the reinforcement cage 100 is composed of a plurality of main reinforcements 110 and a plurality of stirrups 120;

manufacturing a plurality of iron rings with the inner diameter of 30mm, wherein each iron ring is composed of a plurality of steel bars with the inner diameter of 6mm, and the plurality of iron rings are welded on a plurality of main bars 110 on the inner side of a steel bar cage 100;

selecting a water bag 200, wherein the water bag 200 is a cylinder with the diameter of 20mm and is made of a polyurethane polymer film structure;

injecting water into the plurality of water bags 200 through the plurality of water injection switch valves 400 by using an external high-pressure water injection device, and stopping injecting water until the water storage parts 210 of the plurality of water bags 200 are full of water;

the outer surfaces of the water bags 200 are coated with engine oil and placed in the iron rings.

Specifically, in the process of manufacturing the reinforcement cage 100, when a raw material of a reinforcement enters a field, a factory quality certificate or a factory inspection report should be attached, appearance inspection should be performed, reinforcements that are not qualified in appearance inspection should be removed in time, and it is checked whether a mark on each bundle or disc of reinforcements is the same as the model and batch number of the factory quality certificate, and whether the specification and model meet design requirements. A plurality of main reinforcements 110, stirrups 120 and reinforcing ribs are welded into a reinforcement cage 100 framework according to a design drawing, the reinforcement cage is assembled on site, the position is accurate, the welding is firm, the formed framework is stacked in an overhead mode, the formed framework can be used after being qualified through quality inspection and supervision inspection, and hidden inspection records are made carefully. Meanwhile, when the external high-pressure water injection device is connected to the water injection switch valve 400, the water bag 200 needs to be injected with water after the calculated pressure value meets the standard. And applying engine oil to the outer surfaces of the water bags 200 so as to be convenient for later demolding and taking out.

In some embodiments of the invention, the grouting of the hole bottom comprises the following steps:

discharging the water in the plurality of water pockets 200 through the plurality of water injection on-off valves 400;

taking out a plurality of water bags 200 from the sand layer geological pile foundation hole bottom grouting device;

cleaning a plurality of pore passages formed by the pile foundation after the water bags 200 are taken out;

and performing hole bottom grouting on the plurality of the pore channels.

Specifically, after the strength of the pile foundation concrete reaches a design value, hole bottom grouting can be performed. Firstly, part of the water in the water bag 200 is discharged through the water filling switch valve 400 at the top of the water bag 200, the pressure in the water bag 200 is eliminated, and then the water bag 200 is pumped out. Then chiseling the pile head to the designed elevation, adopting a high-pressure water cleaning water bag 200 to pump away the hole channel reserved in the pile foundation, and finally carrying out hole bottom grouting through the hole channel. Wherein, the two grouting pipes adopt circulating grouting during grouting, the grouting water cement ratio is 0.6:1 to 0.8:1, the final hole pressure is 3.5 to 5MPa, and the grouting amount is about 2.5 t.

To better facilitate understanding by those skilled in the art, a preferred embodiment of the present invention is provided as follows:

(1) excavating a reservoir and a sedimentation tank:

the construction site is reasonably arranged according to design requirements, and the site is leveled, sundries are removed, soft soil is replaced, and ramming is carried out compactly. And digging drainage ditches around the hole openings, and preparing a drainage system. When a driving route is planned, keeping a certain distance between the access and the drilling position; so as to avoid influencing the stability of the hole wall; the temporary spoil needs to be stacked beyond 5m away from the hole, the pressure of the hole wall cannot be increased, and the spoil can be transferred to a spoil site in time.

And (4) conveying the slurry by a slurry pump and a slurry discharge pipe. Digging pits outside 2 meters of the side line of the pile hole to serve as a sedimentation tank and a reservoir, wherein the size of the sedimentation tank and the reservoir meets the requirements of sediment and slurry change of the pile, the size of the sedimentation tank and the size of the reservoir are both 4m (length) multiplied by 3m (width) multiplied by 3m (height), the sedimentation tank and the reservoir are isolated by sand bags, and slurry is precipitated and then flows into the reservoir through isolation to ensure the cyclic utilization of water resources.

(2) Measuring and lofting the pile foundation and embedding a steel casing:

firstly, checking and checking the coordinate base points, the leveling base points and the measurement data thereof provided by a design unit, and introducing the checking and checking into a construction site. And then measuring the central position of each drilled pile by using a total station according to the design, wherein the center of the drill bit or the drill rod is overlapped with the center of the steel casing. The periphery of the steel casing is provided with 2-4 pile protectors, cement mortar is used for reinforcement, an obvious mark is arranged, and the center position of the pile is measured by a cross method at any time. Pile position lofting, the position lofting of pile foundation is carried out according to "from whole to local principle", when the elevation lofting of driling, should in time carry out the recheck to the elevation of lofting. And accurately lofting the position of each pile point by using a total station, and controlling the error of the pile point within the standard requirement.

The embedded steel protection cylinder is made of 8-10 mm steel plates, and the inner diameter of the embedded steel protection cylinder is required to be as follows: selecting an embedded steel pile casing with the diameter 200mm larger than the designed drilled pile according to requirements; the length of the protective cylinder is not less than 2000 mm. The embedding is accurate and stable, the deviation between the center and the center of the pile position is not more than 5cm, the inclination is not allowed to be more than 1% of the depth of the pile, and the embedding inclination can be measured by the levelness of the horizontal plate.

(3) Drilling construction:

and positioning the drilling machine, wherein a total station instrument is required to be used for measurement in the positioning process, the center of the drill bit is required to be aligned to the center of the steel casing, the hole position is required to be rechecked at any time in the drilling process, the center of the hole position is ensured to be consistent with the design center of the pile foundation, otherwise, the reason is required to be searched, and the deviation is corrected in time.

When drilling in the hole opening stage, more clay is put in the hole, a proper amount of flaky stones with the particle size not larger than 15cm are added, low-stroke punching and smashing are carried out to make slurry, and the specific gravity of the slurry is controlled to be 1.1-1.3. And when the drill reaches 0.5-1.5 m, backfilling the clay. Continue to pound with low stroke. This is repeated two or three times, and repeated several times if necessary. If the water loss phenomenon is found in the punching process, water should be immediately supplemented and clay should be put in. If the slurry is too thick and the footage is slow, the slurry should be pumped and changed; during drilling, the hole position is checked at any time until the hole position is drilled to the designed stratum.

When the drilling depth reaches the design requirement, the hole depth, the hole diameter and the hole shape are inspected by using the measuring rope and the hole inspection device immediately, the drilled hole is cleaned through water circulation of the water inlet pipe and the slurry discharge pipe, the thickness of the sediment at the bottom of the hole is inspected after the hole cleaning is completed, and after the design requirement is met, the supervision engineer is informed to approve the drilled hole, and the subsequent installation of the reinforcement cage 100 can be prepared after the supervision engineer approves the drilled hole.

(4) The sand bed geological pile foundation hole bottom grouting device manufactured by the embodiment of the first aspect of the invention comprises the following steps:

specifically, in the process of manufacturing the reinforcement cage 100, when a raw material of a reinforcement enters a field, a factory quality certificate or a factory inspection report should be attached, appearance inspection should be performed, reinforcements that are not qualified in appearance inspection should be removed in time, and it is checked whether a mark on each bundle or disc of reinforcements is the same as the model and batch number of the factory quality certificate, and whether the specification and model meet design requirements.

A plurality of main reinforcements 110, stirrups 120 and reinforcing ribs are welded into a reinforcement cage 100 framework according to a design drawing, the reinforcement cage is assembled on site, the position is accurate, the welding is firm, the formed framework is stacked in an overhead mode, the formed framework can be used after being qualified through quality inspection and supervision inspection, and hidden inspection records are made carefully.

Begin to make fixed guiding mechanism 300, the 30 mm's of internal diameter hoop of making a plurality of internal diameter 6mm reinforcing bar, the hoop welds on the main muscle 110 of steel reinforcement cage 100, the interval is 2m from top to bottom between the hoop, the hoop is not arranged to the bent part on the main muscle 110 top of steel reinforcement cage 100, the hoop that is located the lowest is apart from steel reinforcement cage 100 bottom 50cm, two sets of fixed guiding mechanism 300 of steel reinforcement cage 100 installation at least, two at least fixed guiding units promptly, every fixed guiding mechanism 300 in every fixed guiding unit is at the inboard symmetrical welding installation of steel reinforcement cage 100.

(5) Installing the sand layer geological pile foundation hole bottom grouting device into a drilled pile hole:

after the framework of the reinforcement cage 100 is transported to the position near the hole site, the framework is hoisted in sections, the upper main reinforcement 110 and the lower main reinforcement 110 are aligned, the upper axis and the lower axis of the reinforcement cage 100 are consistent, the lap joint positions of the main reinforcements 110 are staggered by more than 50%, and the adjacent two sections of the framework of the reinforcement cage 100 are connected in a welding manner. After the reinforcement cage 100 is placed into the hole, the total station rechecks that the center line deviation of the reinforcement cage 100 is within an allowable range, uses phi 28 thick steel bars as positioning steel bars, is welded and fixed with the protective sleeve in a cross shape along the outer edge of the reinforcement cage 100, positions the reinforcement cage 100, and can prevent the steel cage from floating upwards or deviating during concrete pouring.

(6) And (3) injecting water into the water bag and installing:

the water bag 200 adopts the cylindrical polyurethane polymer membrane structure of diameter 20mm, and inside can bear the water injection pressure and should be greater than concrete perfusion pressure value under water, and the water bag 200 top is provided with water injection ooff valve 400, and water injection ooff valve 400 is connected to outside high pressure water injection device, gives withstand voltage water bag 200 water injection according to the calculated pressure value. And after the water is injected, the machine oil is coated on the outer surface of the water bag 200, so that later-stage demoulding is facilitated. Finally, the water bag 200 is inserted into the fixing and guiding device.

(7) Carrying out concrete pouring on the pile foundation:

the concrete pouring is called underwater concrete pouring, and before the underwater concrete pouring, hole cleaning treatment is carried out on hole bottom sediments, and the concrete pouring can be carried out after the requirements are met. Arranging a special person to measure the buried depth of the guide pipe and the height difference of the concrete pouring surface inside and outside the pipe during concrete pouring; the minimum quantity of the first batch of bottom sealing concrete can meet the requirement that the first embedding depth of the guide pipe is more than 1.0m, after the first batch of concrete enters a hole, the concrete is continuously poured, the embedding depth of the guide pipe is ensured to be 2.0-6.0 m, if the embedding depth of the guide pipe exceeds 6m, the guide pipe is sequentially dismantled from the direction opposite to the hole opening, the embedding depth of the guide pipe is ensured to meet the requirement when the pipe is dismantled, the height difference between the concrete in the hole and the hole opening is measured by applying a measuring rope before the pipe is dismantled every time, and the pipe dismantling length is determined by calculation. And controlling the extracting speed of the conduit, and strictly lifting the conduit out of the concrete pouring surface. After the bottom sealing concrete is finished, measures for slowing down the concrete inlet hole are adopted during pouring, so that the steel reinforcement framework is prevented from floating upwards. The underwater concrete pouring is higher than the designed elevation by 0.5 m.

(8) Grouting the pile bottom of the pore channel:

and when the strength of the pile foundation concrete reaches a design value, grouting at the bottom of the hole can be carried out. Firstly, part of the water in the water bag 200 is discharged through the water filling switch valve 400 at the top of the water bag 200, the pressure in the water bag 200 is eliminated, and then the water bag 200 is pumped out. Then the pile head is chiseled to the designed elevation, the hole channel reserved on the pile foundation after the high-pressure water cleaning water bag 200 is pumped away is adopted, and finally hole bottom grouting is carried out through the hole channel. Wherein, the two grouting pipes adopt circulating grouting during grouting, the grouting water cement ratio is 0.6:1 to 0.8:1, the final hole pressure is 3.5 to 5MPa, and the grouting amount is about 2.5 t.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like 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 do not necessarily 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.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. The utility model provides a sand bed geological pile foundation hole bottom slip casting device which characterized in that includes:

a reinforcement cage;

each water bag comprises a water storage part and a water injection part, the water storage part is arranged along the axial direction of the reinforcement cage, and the water injection part is positioned at the top of the water bag;

the fixing and guiding mechanisms are arranged on the inner side of the reinforcement cage and connected with main reinforcements of the reinforcement cage, and are used for limiting the positions of the water bags in the reinforcement cage;

and the water injection switch valves are connected with the water injection parts in a one-to-one correspondence manner.

2. The sand layer geological pile foundation hole bottom grouting device according to claim 1, characterized in that a plurality of the fixed guide mechanisms are uniformly divided into a plurality of fixed guide units according to the number, the fixed guide units are arranged at intervals in the vertical direction on the inner side of the reinforcement cage, and each of the fixed guide mechanisms in each of the fixed guide units is positioned on the same horizontal plane and arranged in a ring shape at equal intervals.

3. The sand layer geological pile foundation hole bottom grouting device according to claim 1 or 2, characterized in that a plurality of the fixed guide mechanisms are a plurality of 30mm inner diameter iron rings, each of the iron rings is made of 6mm inner diameter steel bars, and the plurality of iron rings are welded with a plurality of the main bars.

4. The sand geological pile foundation hole bottom grouting device of claim 1, wherein the plurality of water bags are a plurality of cylinders with the diameter of 20 mm.

5. The sand layer geological pile foundation hole bottom grouting device as claimed in claim 1 or 4, wherein each water bag is of a polyurethane polymer film structure.

6. The sand geological pile foundation hole bottom grouting device of claim 1, wherein the water injection pressure borne by the interior of each water bag is greater than the concrete injection pressure.

7. The sand layer geological pile foundation hole bottom grouting device according to claim 1, wherein a plurality of water injection switch valves are respectively arranged at the top ends of a plurality of water injection parts.

8. A sand bed geological pile foundation hole bottom grouting construction method is characterized by comprising the following steps:

excavating a reservoir and a sedimentation tank;

measuring and lofting the pile foundation and embedding a steel casing;

drilling a stratum, and installing the sand layer geological pile foundation hole bottom grouting device according to any one of claims 1 to 7 into the drilled pile hole;

carrying out concrete pouring on the pile foundation;

and grouting the bottom of the hole.

9. The sand layer geological pile foundation hole bottom grouting construction method according to claim 8, characterized in that the sand layer geological pile foundation hole bottom grouting device is obtained by the following steps:

manufacturing a reinforcement cage, wherein the reinforcement cage is composed of a plurality of main reinforcements and a plurality of stirrups;

manufacturing a plurality of iron rings with the inner diameter of 30mm, wherein each iron ring is composed of a plurality of steel bars with the inner diameter of 6mm, and the plurality of iron rings are welded on the plurality of main bars on the inner side of the steel bar cage;

selecting a water bag, wherein the water bag is a cylinder with the diameter of 20mm and is made of a polyurethane polymer film structure;

injecting water into the water bags by using an external high-pressure water injection device through a plurality of water injection switch valves until water storage parts of the water bags are full of water, and stopping injecting the water;

and coating engine oil on the outer surfaces of the water bags, and placing the water bags in the iron rings.

10. The sand layer geological pile foundation hole bottom grouting construction method according to claim 9, wherein the grouting of the hole bottom comprises the following steps:

discharging the water in the water bags through the water injection switch valves;

taking out a plurality of water bags from the sand layer geological pile foundation hole bottom grouting device;

cleaning a plurality of pore passages formed by the pile foundation after the water bags are taken out;

and performing hole bottom grouting on the plurality of the pore channels.

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