阅读说明：本技术 一种改进型现浇cfg桩与其复合地基结构及其施工方法 (Improved cast-in-place CFG pile and composite foundation structure thereof and construction method thereof ) 是由 刘家赫 于 2020-06-04 设计创作，主要内容包括：一种改进型现浇CFG桩与其复合地基结构及其施工方法,属于建筑领域,所述现浇CFG桩中间水泥浆浇注管,桩底设置有桩底部件,桩底部件上有多个底部连通管,底部连通管端部有压力爆破片,中间水泥浆浇注管延伸至地上,现浇CFG桩阵列设置在地基中,其上端为褥垫层,现浇CFG桩以及褥垫层的混凝土中按比例添加有垃圾混凝土,CFG桩的底部形成有桩底形成有桩底基座,周边形成有树根桩,本发明可有效利用垃圾混凝土形成现浇CFG桩、并在现浇CFG桩周边形成树根桩,进一步降低地基的下沉,强化现浇CFG桩承载强度,拓宽现浇CFG桩使用的土质层。(The invention relates to an improved cast-in-situ CFG pile and a composite foundation structure thereof and a construction method thereof, belonging to the field of buildings, wherein a middle cement slurry pouring pipe of the cast-in-situ CFG pile is provided with a pile bottom part, the pile bottom part is provided with a plurality of bottom communicating pipes, the end parts of the bottom communicating pipes are provided with pressure rupture discs, the middle cement slurry pouring pipe extends to the ground, a cast-in-situ CFG pile array is arranged in the foundation, the upper end of the cast-in-situ CFG pile is a mattress layer, garbage concrete is proportionally added into the concrete of the cast-in-situ CFG pile and the mattress layer, the bottom of the CFG pile is provided with a pile bottom base, and the periphery of the CFG pile is provided with a tree root pile.)

1. The utility model provides a cast-in-place CFG stake of improved generation, cast-in-place CFG stake is used in the foundation structure of compound CFG stake, its characterized in that: the bottom of the cast-in-place CFG pile is provided with a pile bottom component, the periphery of a cast-in-place CFG pile main body is provided with an intermediate communicating pipe and a positioning ring, the pile bottom component and the intermediate communicating pipe are connected and communicated with an intermediate cement slurry pouring pipe, the bottom of the cast-in-place CFG pile is formed by the pile bottom component and is formed by a pile bottom, a pile bottom base is formed by cement slurry, the periphery of the CFG pile main body is formed by a tree root pile by cement slurry, the cast-in-place CFG pile is formed by cement, fly ash, gravel, sand, garbage concrete, graphene and boron graphene, and the cement, the fly ash, the gravel: the weight percentage of the boron-alkene is 35-42 percent, 10-15 percent and 10-15 percent: 8-12%: 0.8-1.5%: 0.01 to 0.5 percent.

2. The utility model provides a cast-in-place CFG stake of improved generation and composite foundation structure thereof, includes the rubbish concrete, its characterized in that: the CFG pile is a cast-in-place CFG pile, the cast-in-place CFG pile is cast in a long spiral drilling hole, an intermediate cement slurry pouring pipe in the height direction is arranged in the long spiral drilling hole, a pile bottom part is arranged at the pile bottom of the cast-in-place CFG pile, a plurality of bottom communicating pipes are arranged on the pile bottom part, the inner ends of the bottom communicating pipes are connected and communicated with an axial cement slurry pouring pipe, the inner ends of the bottom communicating pipes extend to the periphery of the pile bottom part, the diameter of the bottom communicating pipes is smaller than or equal to the diameter of the long spiral drilling hole, a pressure bursting sheet is arranged at the end part of the bottom communicating pipes, the axial cement slurry pouring pipe is communicated and communicated with the intermediate cement slurry pouring pipe in the cast-in-place CFG pile in a butt joint mode, the intermediate cement slurry pouring pipe is arranged on the intermediate cement slurry pouring pipe, the intermediate, the concrete of the cast-in-place CFG pile and the mattress layer is added with garbage concrete in proportion, the bottom of the cast-in-place CFG pile is provided with a pile bottom, a pile bottom base is formed by cement paste, and the periphery of the CFG pile main body is provided with a tree root pile by the cement paste.

3. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 2, wherein: be provided with middle grout pouring pipe in the cast-in-place CFG stake, be provided with a plurality of middle communicating pipes according to a take the altitude on the middle grout pouring pipe direction of height, middle grout pouring pipe is connected the intercommunication with a plurality of middle communicating pipes, and middle communicating pipe outer end is provided with the pressure rupture disk.

4. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 2, wherein: the pile bottom part is a cylindrical part, a single-layer or double-layer inverted cone-shaped part, an acute angle-shaped annular triangular step is formed on the periphery between an upper layer structure and a lower layer structure in the double-layer inverted cone-shaped structure, a pressure rupture disc at the end of a bottom communicating pipe is arranged on the periphery of an inclined edge of the triangular step part according to a certain graduation, and the bottom communicating pipe is connected and communicated with a middle cement slurry pouring pipe in the vertical direction.

5. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 2, wherein: the axial grout pouring pipe of the pile bottom component is provided with an internal thread at the upper end in communication, the lower end of the middle grout pouring pipe is provided with an external thread, and the external thread at the lower end of the middle grout pouring pipe is in threaded connection with the internal thread of the pile bottom component.

6. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 2, wherein: the pile bottom base and tree root pile composition comprises 85-95% of cement, 4-15% of hemp cut, 0.5-2% of graphene and 0.01-0.5% of boron alkene by weight ratio.

7. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 3, wherein: the end parts of the intermediate communicating pipes are provided with positioning rings, round holes are formed in the peripheries of the positioning rings, and the end parts of the intermediate communicating pipes are arranged in the round holes.

8. An improved cast-in-situ CFG pile and its composite foundation structure as claimed in claim 3, wherein: and the included angles between the bottom communicating pipes or the middle communicating pipes and the cement paste pouring pipes are within 0-180 degrees.

9. The construction method of the improved cast-in-place CFG pile and the composite foundation structure thereof as claimed in claims 1-9 comprises the following steps:

1) long spiral drill holes and CFG concrete pile bottoms are arrayed on the foundation according to the size required by the design by using a long spiral drilling machine,

2) welding and connecting an intermediate communicating pipe and a positioning ring thereof on an intermediate cement slurry pouring pipe according to the designed height;

3) connecting a threaded connecting part of the inverted cone component, an inverted cone threaded connecting part of the inverted cone component with a double-layer structure or a threaded connecting port of the inverted cone component with a single-layer structure on the pile bottom component by a threaded connecting connector;

4) arranging a pile bottom part connected with an intermediate cement slurry pouring pipe, an intermediate communicating pipe and a positioning ring thereof to the bottom of the long spiral drilling hole;

5) the weight percentage of cement, fly ash, broken stone, sand, garbage concrete, graphene and boron alkene is 35-42 percent to 10-15 percent: 8-12%: 0.8-1.5%: 0.01-0.5 percent, stirring the concrete, and pouring the concrete into the long spiral drilling hole;

6) stirring cement sizing materials according to the weight ratio of 85-95% of cement, 4-15% of hemp knives and 0.5-2% of graphene, and grouting in the intermediate cement slurry pouring pipe by using grouting equipment;

7) after the pressure in the intermediate cement slurry pouring pipe 35 reaches a certain pressure, the pressure rupture disc at the end part of the bottom communicating pipe 36a is extruded and crushed, a pressure gauge of the slurry in the intermediate cement slurry pouring pipe on the grouting equipment indicates that the pressure is reduced, the cement slurry is extruded to the gap at the periphery of the cast-in-place CFG pile, when the pressure rises again to a certain degree, the pressure rupture disc at the end part of the intermediate communicating pipe of the cast-in-place CFG pile is extruded and the cement slurry is extruded to the periphery of the cast-in-place CFG pile;

8) forming a pile bottom base at the bottom of the cast-in-place CFG pile, forming a tree root pile on the outer side of the periphery of the cast-in-place CFG pile, and extruding cement paste from the bottom surface of the periphery of the cast-in-place CFG pile when the pressure exceeds the pressure of the front two sides;

9) paving a mattress layer added with garbage concrete on the inter-pile soil and the cast-in-place CFG pile to form a garbage concrete CFG mattress layer;

10) and finishing the whole composite foundation structure of the cast-in-situ CFG pile.

Technical Field

The invention relates to a CFG (cement fly-ash gravel) and pile composite foundation structure and a construction method thereof, in particular to an improved cast-in-place CFG pile, a composite foundation structure and a construction method thereof, belonging to the field of buildings.

Background

Bond strength piles are representative of composite foundations, and are used in high-rise and super high-rise buildings. The CFG pile is a cement fly ash gravel pile for short (namely, cement fly ash gravel pile). It is a composite foundation formed by high-bonding-strength piles formed by mixing cement, fly ash, broken stone, stone chips or sand with water, and soil between piles and mattress layers. The CFG pile composite foundation is connected with the foundation through the mattress layer, and whether the pile end falls on a common soil layer or a hard soil layer, the soil between the piles can be guaranteed to participate in the work all the time. Because the strength and modulus of the pile body are larger than those of the soil between the piles, the stress of the pile top is larger than the surface stress of the soil between the piles under the action of load. The piles can transmit the borne load to a deeper soil layer and correspondingly reduce the load borne by soil among the piles. Therefore, the bearing capacity of the composite foundation is improved and the deformation is reduced under the action of the pile, and in addition, the CFG pile is not provided with ribs, and the pile body utilizes industrial waste fly ash as an admixture, so that the construction cost is greatly reduced.

The construction of the cement fly ash gravel pile should select corresponding construction technology according to design requirements and field conditions, and should be executed according to the current relevant national specifications: (1) the long spiral drilling pouring pile is suitable for the cohesive soil, silt and artificial filling foundation above the underground water level; (2) slurry wall protection, drilling and pouring to form a pile, which is suitable for the foundation distributed by cohesive soil, silt, sandy soil, artificial filling, gravel soil and weathered rock stratum; (3) long spiral drilling, and forming piles by pumping mixture in pipes, which is suitable for foundations such as cohesive soil, silt, sand and the like, and places with strict requirements on noise and slurry pollution; and (4) the immersed tube is poured into a pile, and the pile is suitable for artificial filling of cohesive soil, silt soil and mucky soil and a foundation without a dense thick sand layer. Because the traditional CFG pile is limited by the soil quality of the foundation, and is not used in any address condition, if the soil quality of the pile bottom is soft, the foundation sinking phenomenon can occur, particularly, in recent years, with the development of urban buildings to high-rise buildings, the requirement on the foundation is higher and higher, how to apply the CFG pile to the foundations of various geology and prevent the foundation from sinking is a new subject, in addition, because the existing CFG pile is mostly cast-in-place, the transportation problem of the raw materials such as sand stone, cement and the like or the concrete which is mixed into the cement exists, if the CFG pile is transported to a newly opened building plate far away from the urban area, but if the CFG pile is limited by transportation vehicles and the like in the urban area, certain difficulty can be brought to the construction, in addition, the construction period of the cast-in-place CFG pile is long, in addition to the factors such as environmental protection, the construction time can be delayed, for some projects with tight construction, ensuring the construction progress is a very important issue.

A mattress layer is a method for solving the problem of uneven foundation in a CFG composite foundation. When building is on rock foundation and clay foundation, it adopts bedding layer (graded sand stone) on the rock foundation.

In addition, with the current advance of urbanization and the improvement of shed areas, a large amount of concrete waste is generated, which brings great environmental load, and in order to protect the environment, a plurality of units are limited to a certain extent in the research on recycling of concrete waste and the popularization and application process of concrete waste, which is a major subject faced at present.

Previously, a prefabricated hollow pipe structure for forming a tree root pile and a pile bottom base with patent number 20182185697.8 was published, the bottom of the first prefabricated hollow pipe foundation pile was provided with an inverted cone structure with a downward cone tip, and fig. 5 is a schematic diagram of a longitudinal section structure of a prefabricated hollow pipe provided with an intermediate cement slurry pouring pipe. Fig. 6 is a schematic view of a horizontal sectional structure taken along a-a in fig. 5. Prefabricated hollow tube as the foundation pile comprises many, many prefabricated hollow tubes include prefabricated hollow tube 31 of first root and many in the middle of in addition prefabricated hollow tube 32, 33 is the pipe wall of prefabricated hollow tube, 40 is the connecting portion of prefabricated hollow tube, be provided with middle grout pouring pipe 35 in the middle of the prefabricated hollow tube in 34, the prefabricated hollow tube 31 bottom of first root is provided with the decurrent back taper part 30 of awl point, the cone peripheral distribution of back taper part 30 has a plurality of pressure rupture discs 37, a plurality of pressure rupture discs 37 that distribute on the back taper part 30 respectively with the middle grout pouring pipe 35 of the middle setting of cavity 34 in the middle of the prefabricated hollow tube between be connected with a plurality of communicating pipes respectively, promptly: the outer ends of the bottom communicating tubes 36a are respectively connected with the pressure rupture discs 37 on the inverted conical part in a sealing way; meanwhile, a plurality of pressure rupture discs 37 are arranged on the same height of the outer periphery of the prefabricated hollow pipe 32, the pressure rupture discs 37 are connected and communicated with a cement paste pouring pipe communicating pipe 35 in the prefabricated hollow pipe 32 through an intermediate communicating pipe 35b, the outer ends of a plurality of intermediate communicating pipes 36b are respectively in sealing connection with the plurality of pressure rupture discs 37, cement paste is poured through the cement paste pouring pipe 35, so that the plurality of pressure rupture discs 37 distributed on the periphery of the inverted cone-shaped component 30 and the plurality of pressure rupture discs 37 arranged on the same height of the periphery of the prefabricated hollow pipe 32 are ruptured, a pile bottom base 41 is formed at the bottom of the outer side of the periphery of the inverted cone-shaped component 30, and a tree root pile 42 is formed at the outer side of the periphery of the prefabricated.

The prefabricated hollow pipe foundation pile body is communicated with the pressure rupture disk on the periphery of the pile body through the cement slurry pouring pipe in the vertical direction and the communicating pipe, and a pile bottom base and a tree root pile can be formed on the pile bottom and the periphery of the pile body.

Graphene as a new material has various characteristics in various fields, and can be applied to various fields, and a team of the university of uk egkset designs a technology, graphene sheets are suspended in water, then the water is mixed with traditional concrete components (such as cement and aggregate), and tests show that compared with ordinary concrete, the concrete added with graphene has the advantages that the compressive strength is improved by 146%, the bending tensile strength is improved by 79.5%, and the water seepage rate is reduced by nearly 400%. The increased strength and water resistance should allow structures made with concrete to last longer. This means that their production without the need to frequently replace the cement used in the concrete is a major source of carbon dioxide emissions. Particularly, in recent years, with the mass production of graphene in China, the price of Chinese cabbage falls from the original daily price, and the graphene also has a certain application in concrete.

The boron alkene is a two-dimensional plane structure formed by boron elements, and the energy band structure and the novel quantum effect of the Dirac cone are endowed by the unique two-dimensional hexagonal honeycomb structure. Following graphene, scientists desire to find more two-dimensional materials with superior properties. The boron graphene, known as graphene "brothers", has properties that are similar to and exceed those of graphene, and its applications are constantly being developed.

At present, a CFG pile is a cast-in-place structure, and how to meet the use requirements in more geological conditions, how to improve the bearing strength of the CFG pile, reinforce the disturbed soft soil at the bottom of the CFG pile in a drill hole, prevent the foundation sinking phenomenon, and reduce the load of the CFG pile and the sinking of the foundation is a new subject in the construction process.

Disclosure of Invention

Aiming at the problems that the existing CFG pile is limited by the soil quality of a foundation in the construction process, and the bearing strength and the sinking rate are to be further improved, the invention provides an improved cast-in-situ CFG pile and a composite foundation structure thereof, aiming at effectively utilizing garbage concrete to form the cast-in-situ CFG pile and form a tree root pile at the periphery of the cast-in-situ CFG pile, further reducing the sinking of the foundation, strengthening the bearing strength of the CFG pile and widening the soil layer used by the CFG pile.

The technical scheme of the invention is as follows: the utility model provides an improved generation cast-in-place CFG stake, cast-in-place CFG stake is used in the foundation structure of compound CFG stake, the bottom of cast-in-place CFG stake is provided with pile foot part, cast-in-place CFG stake main part periphery is provided with middle communicating pipe and holding ring, pile foot part, middle communicating pipe and middle grout pouring pipe connection intercommunication, cast-in-place CFG stake bottom utilizes pile foot part to be formed with the pile foot and utilizes grout to be formed with the pile foot base, CFG stake main part periphery utilizes grout to be formed with the root stake, cast-in-place CFG stake comprises cement, fly ash, rubble, sand, rubbish concrete, graphite alkene, boron alkene, cement: fly ash: rubble: sand: rubbish concrete: graphite alkene: the weight percentage of the boron-alkene is 35-42 percent, 10-15 percent and 10-15 percent: 8-12%: 0.8-1.5%: 0.01 to 0.5 percent.

An improved cast-in-situ CFG pile and a composite foundation structure thereof comprise garbage concrete, wherein the CFG pile is a cast-in-situ CFG pile, the cast-in-situ CFG pile is cast in a long spiral drill hole, an intermediate cement slurry casting pipe in the height direction is arranged in the long spiral drill hole, a pile bottom part is arranged at the pile bottom of the cast-in-situ CFG pile, a plurality of bottom communicating pipes are arranged on the pile bottom part, the inner ends of the bottom communicating pipes are connected and communicated with an axial cement slurry casting pipe, the inner ends of the bottom communicating pipes extend to the periphery of the pile bottom part, the diameter of each bottom communicating pipe is smaller than or equal to the diameter of the long spiral drill hole, a pressure bursting sheet is arranged at the end part of each bottom communicating pipe, the axial cement slurry casting pipe is communicated with the intermediate cement slurry casting pipe in the cast-in-situ CF, the method comprises the following steps that a plurality of cast-in-place CFG pile arrays are arranged in a foundation, a mattress layer is laid at the upper end of each cast-in-place CFG pile, garbage concrete is added into concrete of the cast-in-place CFG piles and the mattress layer in proportion, pile bottoms are formed at the bottoms of the cast-in-place CFG piles, pile bottom bases are formed by utilizing cement paste, and root piles are formed at the periphery of a CFG pile main body by utilizing the cement paste;

further, an intermediate cement slurry pouring pipe is arranged in the cast-in-place CFG pile, a plurality of intermediate communicating pipes are arranged at a certain height in the height direction of the intermediate cement slurry pouring pipe, the intermediate cement slurry pouring pipe is connected and communicated with the intermediate communicating pipes, and a pressure rupture disc is arranged at the outer end of each intermediate communicating pipe;

further, the pile bottom part is a cylindrical part, a single-layer or double-layer inverted cone-shaped part, an acute angle-shaped annular triangular step is formed on the periphery between an upper layer structure and a lower layer structure in the double-layer inverted cone-shaped structure, a pressure rupture disc at the end of a bottom communicating pipe is arranged on the periphery of the bevel edge of the triangular step part according to a certain graduation, and the bottom communicating pipe is connected and communicated with a middle cement slurry pouring pipe in the vertical direction;

further, the upper end of the axial cement slurry pouring pipe of the pile bottom component is provided with internal threads, the lower end of the intermediate cement slurry pouring pipe is provided with external threads, and the external threads at the lower end of the intermediate cement slurry pouring pipe are in threaded connection with the internal threads of the pile bottom component;

further, the pile bottom base and the tree root pile composition comprise 85-95% of cement, 4-15% of hemp cut, 0.5-2% of graphene and 0.01-0.5% of boron alkene by weight ratio;

furthermore, positioning rings are arranged at the end parts of the intermediate communicating pipes, round holes are formed in the peripheries of the positioning rings, and the end parts of the intermediate communicating pipes are arranged in the round holes;

furthermore, the included angle between the bottom communicating pipes or the middle communicating pipes and the cement paste pouring pipes is within 0-180 degrees.

The construction method of the improved cast-in-place CFG pile and the composite foundation structure thereof is as follows:

1) long spiral drill holes and CFG concrete pile bottoms are arrayed on the foundation according to the size required by the design by using a long spiral drilling machine,

2) welding and connecting an intermediate communicating pipe and a positioning ring thereof on an intermediate cement slurry pouring pipe according to the designed height;

3) connecting a threaded connecting part of the inverted cone component, an inverted cone threaded connecting part of the inverted cone component with a double-layer structure or a threaded connecting port of the inverted cone component with a single-layer structure on the pile bottom component by a threaded connecting connector;

4) arranging a pile bottom part connected with an intermediate cement slurry pouring pipe, an intermediate communicating pipe and a positioning ring thereof to the bottom of the long spiral drilling hole;

5) the weight percentage of cement, fly ash, broken stone, sand, garbage concrete, graphene and boron alkene is 35-42 percent to 10-15 percent: 8-12%: 0.8-1.5%: 0.01-0.5 percent, stirring the concrete, and pouring the concrete into the long spiral drilling hole;

6) stirring cement sizing materials according to the weight ratio of 85-95% of cement, 4-15% of hemp knives, 0.5-2% of graphene and 0.01-0.5% of boron alkene, and grouting in the intermediate cement slurry pouring pipe by using grouting equipment;

7) after the pressure in the intermediate cement slurry pouring pipe 35 reaches a certain pressure, the pressure rupture disc at the end part of the bottom communicating pipe 36a is extruded and crushed, a pressure gauge of the slurry in the intermediate cement slurry pouring pipe on the grouting equipment indicates that the pressure is reduced, the cement slurry is extruded to the gap at the periphery of the cast-in-place CFG pile, when the pressure rises again to a certain degree, the pressure rupture disc at the end part of the intermediate communicating pipe of the cast-in-place CFG pile is extruded and the cement slurry is extruded to the periphery of the cast-in-place CFG pile;

8) forming a pile bottom base at the bottom of the cast-in-place CFG pile, forming a tree root pile on the outer side of the periphery of the cast-in-place CFG pile, and extruding cement paste from the bottom surface of the periphery of the cast-in-place CFG pile when the pressure exceeds the pressure of the front two sides;

9) paving a mattress layer added with garbage concrete on the inter-pile soil and the cast-in-place CFG pile to form a garbage concrete CFG mattress layer;

10) and finishing the whole composite foundation structure of the cast-in-situ CFG pile.

The invention has the following positive effects: the pile bottom part is arranged at the pile bottom of the cast-in-place CFG pile 10, so that the pile bottom part is favorable for being connected and communicated with the intermediate cement slurry pouring pipe to form a channel for pouring cement slurry, particularly, a bottom communicating pipe and a pressure rupture disc are arranged in the pile bottom part, the cement slurry can pass through the intermediate cement slurry pouring pipe and the bottom communicating pipe arranged in the pile bottom part, the pressure rupture disc is crushed under the action of pressure, the cement slurry is extruded to the pile bottom and the periphery of the cast-in-place CFG pile, and a pile bottom base is formed at the periphery of the pile bottom of the cast-in-place CFG pile; the plurality of intermediate communicating pipes are arranged in the height direction of the intermediate cement paste pouring pipe at certain intervals, and the positioning rings with holes are arranged outside the end parts of the plurality of intermediate communicating pipes, so that the intermediate cement paste pouring pipe can be prevented from displacing in the pouring process; the middle cement paste pouring pipe is arranged in the cast-in-place CFG pile, so that the stirred cement paste is pressed down by using special cement paste extrusion equipment from the ground, a pile bottom base and peripheral tree root piles are formed at the bottom and the periphery of the cast-in-place CFG pile, the sinking of the cast-in-place CFG pile can be prevented, and the application range of the cast-in-place CFG pile composite foundation can be further expanded; the garbage concrete is mixed and used in the cast-in-place CFG pile and the mattress layer according to the proportion, so that the pollution of the garbage concrete to the environment can be reduced, and the waste utilization is realized; the invention can effectively utilize garbage concrete to form the cast-in-situ CFG pile, reduce the environmental pollution caused by the garbage concrete, further reduce the sinking of the foundation by forming the tree root pile at the periphery of the CFG pile, widen the utilization geology of the cast-in-situ CFG pile, strengthen the bearing strength of the CFG pile and ensure the quality of the building.

Drawings

FIG. 1 is a schematic view of the overall cross-sectional structure of the present invention.

Fig. 2 is a schematic top view of the intermediate communication pipe.

Fig. 3 is a schematic structural view of a cylindrical pile bottom part.

FIG. 4 is a schematic cross-sectional view of a double-layered inverted conical member.

FIG. 5 is a schematic diagram of the longitudinal section of a prefabricated hollow tube provided with an intermediate cement slurry pouring tube.

Fig. 6 is a schematic view of a horizontal cross-section along a-a in fig. 5.

Description of reference numerals: the cast-in-place CFG pile comprises a cast-in-place CFG pile 10, a mattress layer 11, pile soil 12, a pile bottom part 13, a positioning ring 14, a double-layer inverted cone part 15, an inverted cone part threaded connection part 15a, a cylindrical part 16, a threaded connection part 16a, an inverted cone part 30, a first prefabricated hollow pipe 31, a middle prefabricated hollow pipe 32, a pipe wall 33, a prefabricated hollow pipe middle inner cavity 34, a middle cement paste pouring pipe 35, an axial cement paste pouring pipe 35aa, a bottom communicating pipe 36a, a middle communicating pipe 36b, a pressure rupture disc 37, a pile bottom base 41 and a tree root pile 42.

Detailed Description

The following describes in detail a specific embodiment of the present invention with reference to the drawings.

The technical scheme of the invention is that an improved cast-in-situ CFG pile is applied to the cast-in-situ CFG pile, a pile bottom part 13 is arranged at the bottom of a cast-in-situ CFG pile 10, an intermediate communicating pipe 36b is arranged on the periphery of the main body of the cast-in-situ CFG pile 10, the pile bottom part 13 and the intermediate communicating pipe 36b are connected and communicated with an intermediate cement slurry pouring pipe 35, a pile bottom formed by the pile bottom part of the cast-in-situ CFG pile is provided with a pile bottom base 41 formed by cement slurry, a tree root pile 42 formed by the periphery of the main body of the CFG pile is provided with cement slurry, pulverized fuel ash, gravel, sand, garbage concrete and graphene, wherein the cement, the pulverized fuel ash, the gravel, the garbage concrete and the graphene are as: the weight percentage of the boron-alkene is 35-42 percent, 10-15 percent and 10-15 percent: 8-12%: 0.8-1.5%: 0.01 to 0.5 percent.

Embodiments of an improved cast-in-place CFG pile

Wherein, the cement, the fly ash, the broken stone and the sand are used as raw materials in the prior art.

The data of the bearing strength and the sinking rate are comprehensive indexes after the pile bottom base and the tree root pile are added, and the hardness improvement rate is the comparison of the test result of the test block performed under a special testing machine and the test result of the test block in the prior art.

The garbage concrete is prepared by crushing the existing concrete blocks into particles with different sizes between gravel and sand by using a concrete crusher in the prior art, and pouring the concrete formed by adding water into a hole formed by a long spiral drill.

An improved cast-in-situ CFG pile 10 and its composite foundation structure, FIG. 1 is a schematic view of the overall cross-sectional structure of the present invention. The composite foundation structure comprises garbage concrete, the CFG pile is a cast-in-place CFG pile 10, the cast-in-place CFG pile 10 is cast in a long spiral drill hole, a middle cement slurry casting pipe 35 in the height direction is arranged in the long spiral drill hole, a pile bottom part 13 is arranged at the pile bottom of the cast-in-place CFG pile 10, a plurality of bottom communicating pipes 36a are arranged on the pile bottom part 13, the inner ends of the bottom communicating pipes 36a are connected and communicated with an axial cement slurry casting pipe 35a, the inner end of each bottom communicating pipe 36a extends to the periphery of the pile bottom part 13, the diameter of each bottom communicating pipe 36a is smaller than or equal to the diameter of a long spiral drill hole, a pressure bursting sheet 37 is arranged at the end part of each bottom communicating pipe 36a, the axial cement slurry casting pipe 35a is in butt joint communication with the middle cement slurry casting pipe 35 in the cast-in-, the middle cement paste pouring pipe 35 extends to the ground, the cast-in-place CFG pile 10 is arranged in the foundation in an array mode, 12 is soil between piles, a mattress layer 11 is laid at the upper end of the cast-in-place CFG pile 10, garbage concrete is added into the concrete of the cast-in-place CFG pile 10 and the mattress layer 11 in proportion, a pile bottom base 41 is formed at the bottom of the cast-in-place CFG pile 10 through cement paste, and a tree root pile 42 is formed on the periphery of a CFG pile main body through cement paste.

Fig. 2 is a schematic top view of the intermediate communication pipe. An intermediate cement paste pouring pipe 35 is arranged in a long spiral drilling hole of the cast-in-place CFG pile 10, a plurality of intermediate communicating pipes 36b are arranged in the height direction of the intermediate cement paste pouring pipe 35 at certain intervals, the intermediate communicating pipes 36b are one layer or multiple layers, the intermediate cement paste pouring pipe 35 is arranged in the cast-in-place CFG pile 10, the intermediate cement paste pouring pipe 35 is connected and communicated with the intermediate communicating pipes 36b, and a pressure rupture disc 37 is arranged at the outer end of each intermediate communicating pipe 36 b.

The pile bottom part 13 is a cylindrical part 16, an inverted cone part 15 with a double-layer structure or an inverted cone part with a single-layer structure, a threaded connection part of an inverted cone part 15a is arranged, and a threaded connection part 16a is arranged.

The two parts form an annular triangular step with an acute angle shape, the periphery of the bevel edge of the triangular step part is provided with a pressure rupture disc 37 at the pipe end of a bottom communicating pipe 36a according to a certain graduation, and the bottom communicating pipe 36a is communicated with an intermediate cement slurry pouring pipe 35 in the vertical direction in a connecting way. In any of these configurations, the axial cement slurry pouring pipe 35a is provided in the middle, the axial cement slurry pouring pipe 35a is connected to the bottom communicating pipe 36a leading to the outer periphery, and the pressure rupture disk 37 is provided at the end of the bottom communicating pipe 36 a.

In the present embodiment, the cylindrical member 16 is cast and processed, the manufacturing cost is relatively low, and the double-layered inverted cone member 15 or the single-layered inverted cone member has versatility with the prestressed hollow pillar, solid CFG of the prior application.

Fig. 3 is a schematic structural view of a cylindrical pile bottom component, and fig. 4 is a schematic sectional structural view of a double-layer inverted-cone-shaped component, wherein an inner thread is arranged at the upper end of the axial cement slurry pouring pipe 35a of the pile bottom component 13 in a communication mode, an outer thread is arranged at the lower end of the intermediate cement slurry pouring pipe 35, and the outer thread at the lower end of the intermediate cement slurry pouring pipe 35 is in threaded connection with the inner thread of the pile bottom component 13.

The end portions of the intermediate communication pipes 36b are provided with positioning rings, the peripheries of the positioning rings are provided with round holes, and the end portions of the intermediate communication pipes 36b are arranged in the round holes.

The pile bottom base and root pile composition comprises 85-95% of cement, 4-15% of hemp cut, 0.5-2% of graphene and 0.01-0.5% of boron alkene by weight ratio, when in use, water is added, slurry is mixed, a special slurry extruder in the prior art is utilized, a middle cement slurry pouring pipe 35 extrudes a crushing pressure blasting sheet, and the crushing pressure blasting sheet is extruded to the pile bottom or the periphery of a cast-in-situ CFG pile to respectively form the pile bottom base and the root pile. The toughness of the cement can be improved by adding the hemp cut into the cement, the hardness of the cement can be further improved by adding the graphene, and the bearing capacity of the cast-in-situ CFG pile is enhanced.

The included angle between the plurality of bottom communication pipes 36a or the plurality of intermediate communication pipes 36b and the plurality of intermediate communication pipes 36b is within 0 to 180 °.

Although an intermediate grout pouring pipe 35 is used in the present embodiment, the grout pouring pipe may be provided in any longitudinal direction within the cast-in-place CFG pile 10.

Although circular cast-in-place CFG piles are used in the present embodiment, polygonal structures can be formed, but it is relatively difficult to perforate the ground.

The hemp knife can be replaced by asbestos, glass limit and cloth fiber.

An improved cast-in-place CFG pile and a composite foundation structure thereof and a construction method thereof are disclosed, wherein the improved cast-in-place CFG pile and the composite foundation structure thereof are as described above, and the construction method comprises the following steps:

1) long spiral drill holes and CFG concrete pile bottoms are arrayed on the foundation according to the size required by the design by using a long spiral drilling machine,

2) an intermediate communicating pipe 36b and a positioning ring 14 thereof are welded and connected on an intermediate cement slurry pouring pipe 35 according to the designed height;

3) the threaded connection part 16a of the inverted cone-shaped part 13, the inverted cone-shaped part threaded connection part 15a of the inverted cone-shaped part 15 with a double-layer structure or the threaded connection port of the inverted cone-shaped part with a single-layer structure are connected with the pile bottom part 13 through a threaded connection connecting piece, and an intermediate cement paste pouring pipe 35 is connected with the threaded connection port of the inverted cone-shaped part with the single-layer structure through a thread;

4) arranging the pile bottom part 13 connected with the intermediate cement slurry pouring pipe 35, the intermediate communicating pipe 36b and the positioning ring 14 thereof to the bottom of the long spiral drilling hole;

5) the weight percentage of cement, fly ash, broken stone, sand, garbage concrete, graphene and boron alkene is 35-42 percent to 10-15 percent: 8-12%: 0.8-1.5%: 0.01-0.5 percent, stirring the concrete, and pouring the concrete into the long spiral drilling hole;

6) stirring cement sizing materials according to the weight ratio of 85-95% of cement, 4-15% of hemp knives and 0.5-2% of graphene, and grouting into the intermediate cement slurry pouring pipe 35 by using grouting equipment;

7) after the pressure in the intermediate cement slurry pouring pipe 35 reaches a certain pressure, the pressure rupture disc 37 at the end part of the bottom communicating pipe 36a is squeezed and broken, the pressure gauge of the slurry in the intermediate cement slurry pouring pipe 35 on the grouting equipment indicates that the pressure is reduced, the cement slurry is squeezed into the gap at the periphery of the cast-in-place CFG pile 10, when the pressure rises to a certain degree again, the pressure rupture disc 37 at the end part of the intermediate communicating pipe 36b of the cast-in-place CFG pile 10 is squeezed and broken, and the cement slurry is squeezed to the periphery of the cast-in-place CFG pile;

8) a pile bottom base 41 is formed at the bottom of the cast-in-situ CFG pile 10, a tree root pile 42 is formed on the outer side of the periphery of the cast-in-situ CFG pile 10, and cement paste is extruded from the bottom surface of the periphery of the cast-in-situ CFG pile 10 when the pressure exceeds the pressure of the front two sides;

9) paving a mattress layer 11 added with garbage concrete on the inter-pile soil 11 and the cast-in-situ CFG pile 10 to form a garbage concrete CFG mattress layer 11;

10) and finishing the whole composite foundation structure of the cast-in-situ CFG pile.

According to the invention, the pile bottom part 13 is arranged at the pile bottom of the cast-in-place CFG pile 10, so that the connection with the intermediate cement slurry pouring pipe 35 is facilitated, a cement slurry pouring channel is formed, particularly, the bottom communicating pipe 36a and the pressure rupture disc 37 are arranged inside the pile bottom part 13, the cement slurry can be communicated with the bottom communicating pipe 36a arranged inside the pile bottom part 13 through the intermediate cement slurry pouring pipe 35, the pressure rupture disc 37 is crushed under the action of pressure, the cement slurry is extruded to the periphery of the pile bottom of the cast-in-place CFG pile 10, and the pile bottom base 41 is formed at the periphery of the pile bottom of the cast-in-place CFG pile 10; the plurality of intermediate communicating pipes 36b are arranged in the height direction of the intermediate cement paste pouring pipe 35 at certain intervals, and positioning rings with holes are arranged outside the end parts of the plurality of intermediate communicating pipes 36b, so that the intermediate cement paste pouring pipe 35 can be prevented from displacing in the pouring process, in addition, the plurality of intermediate communicating pipes 36b are arranged, the plurality of intermediate communicating pipes 36b are connected, communicated and positioned with the intermediate cement paste pouring pipe 35, cement paste can flow along the intermediate communicating pipes 36b through the intermediate communicating pipes and the intermediate communicating pipes, and after pressure crushes the pressure rupture discs 37 at the end parts of the plurality of intermediate communicating pipes 36b, peripheral root piles 42 can be formed at the periphery of the cast-in-situ CFG pile 10; the middle cement paste pouring pipe 35 is arranged in the cast-in-place CFG pile 10, so that cement paste can be pressed down from the ground by using special cement paste extrusion equipment, and a pile bottom base 41 and a peripheral tree root pile 42 are respectively formed at the bottom and the periphery of the CFG pile, so that the cast-in-place CFG pile 10 can be prevented from sinking, and the application range of the composite foundation of the cast-in-place CFG pile 10 can be further expanded; the garbage concrete is mixed and used in the cast-in-place CFG pile 10 and the mattress layer 11 according to the proportion, so that the pollution of the garbage concrete to the environment can be reduced, and the waste utilization is realized; by adding graphene and boron alkene into concrete and cement slurry, the tensile strength and hardness of the cast-in-situ CFG pile 10, the pile bottom base 41 and the peripheral root pile 42 can be improved, the bearing capacity of the cast-in-situ CFG pile is further improved, the sinking speed is reduced, and the height of the lower layer is reduced. The invention can effectively utilize the garbage concrete to form the cast-in-situ CFG pile 10, reduce the environmental pollution caused by the garbage concrete, further reduce the sinking of the foundation by forming the tree root pile 42 at the periphery of the cast-in-situ CFG pile 10, widen the utilization geology of the cast-in-situ CFG pile 10, strengthen the bearing strength of the CFG pile 10 and ensure the quality of the building.