Combined anti-floating construction structure

Abstract

The combined type anti-floating construction structure comprises a bottom plate, an uplift pile and anti-floating anchor rods, the top of the uplift pile and the tops of the anti-floating anchor rods are fixedly connected with the bottom plate, the anti-floating anchor rods are arranged on the outer side of the uplift pile in the circumferential direction, and a reinforcement cage of the uplift pile and anchor rod steel bars of the anti-floating anchor rods are connected into a whole in the bottom plate. The anti-floating reinforced combined structure has the beneficial effects that the anti-floating capacity can be effectively improved, and the stability of an underground structure is enhanced; the anti-buoyancy force can be better dispersed through the inclination angle and the arrangement mode of the anchor rods, the pressure on a single anchoring body is reduced, the applicability is improved, and the engineering cost is reduced to a certain extent.

Description

Technical Field

[0001] The present application belongs to the technical field of building construction, and specifically relates to a combined anti-floating construction structure. Background Art

[0002] With the rapid development of urban construction, the scale and number of underground projects are increasing. Due to the change of groundwater level and the buoyancy of groundwater, the floating risk faced by underground structures is becoming increasingly prominent. There are various measures to prevent underground structures from floating, including anti-pullout piles, anti-floating anchors (cables), weighting, thickening of basement floors, drainage and precipitation, etc. Among them, the most commonly used are anti-pullout piles and anti-floating anchors.

[0003] Pull-out piles generate large anti-buoyancy through their own weight and the friction between the pile body and the foundation soil. They are particularly suitable for anti-buoyancy of underground structures in areas with high groundwater levels. They can be applied to various geological conditions, including soft soil, hard soil, sandy soil and rock foundations, and their construction technology is mature, with high stability and durability. However, the construction period of pull-out piles is long, the construction process is complex, the overall cost is high, and they have certain impacts on the surrounding environment, such as noise, vibration and soil disturbance. Especially when constructing in densely populated urban areas, additional environmental protection measures need to be taken, which increases the complexity and cost of construction.

[0004] The length and angle of anti-floating anchor rods can be adjusted according to specific geological conditions and engineering requirements. They are flexible to deploy and highly adaptable. At the same time, the material cost is low, no large-scale machinery and equipment are required during the construction process, the construction speed is fast, and the impact on the surrounding environment is small. However, the anti-floating ability of anchor rods is limited. In areas with high groundwater levels or large buoyancy, anchor rods alone may not provide sufficient anti-floating force. It is necessary to increase the number of anchor rods or combine other anti-floating measures. The anti-floating effect of anchor rods in soft soil or loose soil layers is poor, and it is easy to slip or fail. The applicable geological conditions are limited, maintenance is difficult, and rust or failure may occur during long-term use.

[0005] Therefore, the use of a single anti-floating form may have certain advantages under certain specific conditions, but it has obvious disadvantages in terms of anti-floating capacity, construction limitations, economy, long-term stability and scope of application. In order to achieve the best anti-floating effect and economic benefits, it is usually necessary to combine multiple anti-floating technologies and select the most appropriate anti-floating solution based on specific engineering requirements and geological conditions.

[0006] To address the above problems, a combined anti-floating construction structure is proposed by combining anti-pullout piles with anchor rods to achieve the best anti-floating effect and economic benefits. While improving the anti-floating bearing capacity, it also achieves fast and efficient construction and reduces the project cost. Utility Model Content

[0007] The purpose of the present application is to provide a combined anti-floating construction structure to improve the anti-floating ability of underground structures and solve the limitations of a single anti-floating structure.

[0008] The purpose of this application is achieved through the following technical solutions:

[0009] A combined anti-floating construction structure comprises a base plate, anti-pullout piles and anti-floating anchor rods. The tops of the anti-pullout piles and the tops of the anti-floating anchor rods are fixedly connected to the base plate. A plurality of anti-floating anchor rods are arranged on the circumferential outside of the anti-pullout piles. The steel cage of the anti-pullout piles and the anchor steel bars of the anti-floating anchor rods are connected as a whole in the base plate.

[0010] Furthermore, the anti-pullout piles are arranged vertically, and the anti-floating anchor rods are arranged inclinedly.

[0011] Furthermore, the anti-floating anchor rod has an inclination angle of 5° to 15° relative to the vertical line.

[0012] Furthermore, the anti-floating anchor rods are evenly arranged on the circumferential outer side of the pull-out piles, the projection of the anti-floating anchor rods on the horizontal plane is the radial direction of the pull-out piles, and the angle between two adjacent anti-floating anchor rods is the same as the projection angle on the horizontal plane.

[0013] Furthermore, the included angle between the two adjacent anti-floating anchor rods is projected on the horizontal plane at 120° or 90°.

[0014] Furthermore, the base plate includes a cushion layer, a first waterproof coiled material layer, a waterproof protective layer and a base layer which are arranged layer by layer from bottom to top.

[0015] Furthermore, the pull-out pile comprises a pile body and a steel cage inside the pile body, and the top end of the steel cage extends into the bottom plate.

[0016] Furthermore, the anti-floating anchor comprises an anchor body and anchor reinforcement in the anchor body, the top end of the anchor reinforcement extends into the bottom plate, and positioning ribs are arranged circumferentially outward along the lower section of the anchor reinforcement.

[0017] Furthermore, the anti-floating anchor includes a second waterproof membrane layer, a waterproof sleeve, a waterproof paste, a sealing strip and anchor reinforcement. The second waterproof membrane layer is located at the anchor hole mouth, and the upper layer of the second waterproof membrane layer is provided with a waterproof sleeve, which is filled with waterproof paste. The anchor reinforcement passes through the second waterproof membrane layer and is located inside the waterproof sleeve. The waterproof paste is wrapped around the anchor reinforcement, and the anchor reinforcement is provided with a sealing strip located above the waterproof sleeve.

[0018] Furthermore, the anchor rod reinforcement is welded to the reinforcement cage through the bent portion at the top.

[0019] The beneficial effects of the present application are as follows: a combined structure of anti-floating reinforcement is provided, which can effectively improve the anti-floating ability and enhance the stability of the underground structure; the inclination angle and arrangement of the anchor rod enable it to better disperse the anti-floating force, reduce the pressure on a single anchor body, and improve the applicability, thereby reducing the engineering cost to a certain extent.

[0020] The aforementioned main scheme of the present application and its further options can be freely combined to form multiple schemes, all of which are schemes that can be adopted and claimed for protection in the present application; and in the present application, (non-conflicting options) can also be freely combined with each other and with other options. After understanding the present scheme, those skilled in the art can understand that there are many combinations based on the prior art and common knowledge, all of which are technical schemes to be protected by the present application, and they are not exhaustively listed here. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of this application.

[0022] Figure 2 It is a schematic diagram of the anti-floating anchor structure of the present application.

[0023] In the figure: 1-base plate, 2-pull-out pile, 3-anti-floating anchor; 101-cushion, 102-first waterproof membrane layer, 103-waterproof protective layer, 104-foundation layer, 201-pile body, 202-steel cage, 301-second waterproof membrane layer, 302-waterproof sleeve, 303-waterproof paste, 304-sealing strip, 305-anchor steel bar, 306-positioning rib, 307-bending portion, 308-anchor body. DETAILED DESCRIPTION

[0024] The present application is further described below in conjunction with specific embodiments and drawings.

[0025] refer to Figure 1 and Figure 2 As shown, a combined anti-floating construction structure includes a bottom plate 1 and an anti-floating structure under the bottom plate 1, wherein the anti-floating structure includes an anti-pullout pile 2 arranged vertically on the foundation and a plurality of anti-floating anchor rods 3 driven obliquely into the foundation at a certain angle.

[0026] The pull-out pile 2 is a cast-in-place pile, which is formed by mechanically drilling and then hanging a steel cage 202 and pouring underwater concrete. The anti-floating anchor rod 3 is a hot-rolled threaded steel bar. The top of the pull-out pile 2 and the top of the anti-floating anchor rod 3 are both fixedly connected to the bottom plate 1, specifically, they are integrally poured by concrete.

[0027] A plurality of anti-floating anchor rods 3 are arranged on the circumferential outer side of the pull-out piles 2. The pull-out piles 2 are arranged vertically, and the pull-out piles 2 are used to perform anti-floating effect in the center to form an overall vertical anti-floating force. The anti-floating anchor rods 3 are arranged obliquely, and the anti-floating anchor rods 3 are used to perform anti-floating effect in the circumferential direction to form an overall inclined (vertical and horizontal) anti-floating force. The two cooperate to form an overall anti-floating structure.

[0028] The anti-floating anchor rods 3 are evenly arranged on the circumferential outer side of the pull-out pile 2, and the inclination angle of the anti-floating anchor rods 3 relative to the vertical perpendicular line is 5° to 15°. The projection of the anti-floating anchor rods 3 on the horizontal plane is the radial direction of the pull-out pile 2, and the angle between two adjacent anti-floating anchor rods 3 is the same in the horizontal plane projection angle. Preferably, the angle between two adjacent anti-floating anchor rods 3 is 120° (three, trident arrangement) or 90° (four, cross arrangement) in the horizontal plane projection angle.

[0029] Specifically, four anti-floating anchor rods 3 form a group, and the four anchor rods in each group form a quadrangular pyramid structure. The inclination angle between the four anti-floating anchor rods 3 relative to the vertical line is 5-15°; the projection of two adjacent anti-floating anchor rods on the horizontal plane forms an angle of 90°.

[0030] The steel cage 202 of the pull-out pile 2 and the anchor steel bar 305 of the anti-floating anchor 3 are connected as a whole in the base plate 1, that is, not only the pull-out pile 2 and the anti-floating anchor 3 are connected as a whole through the concrete of the base plate 1, but also the steel bars inside the two are connected as a whole, thereby improving the overall force effect.

[0031] The bottom plate 1 includes a cushion layer 101, a first waterproof roll material layer 102, a waterproof protective layer 103 and a base layer 104 arranged layer by layer from bottom to top. The cushion layer 101 is made of concrete, and a waterproof coating plus a first waterproof roll material layer 102 is arranged thereon. The first waterproof roll material layer 102 adopts a self-adhesive polymer modified asphalt waterproof roll material, and the upper layer of the waterproof roll material is provided with fine stone concrete as a waterproof protective layer 103. The cushion layer 101, the first waterproof roll material layer 102 and the waterproof protective layer 103 are constructed first, and then the concrete is constructed to form the base layer 104, so as to connect the pull-out pile 2 and the anti-floating anchor rod 3 as a whole.

[0032] The pull-out pile 2 includes a pile body 201 and a steel cage 202 in the pile body 201. The pile body 201 is a concrete structure. The top of the steel cage 202 extends into the foundation layer of the bottom plate 1. The pull-out pile has a pile diameter of 800 mm and a pile length of 25 m. It is excavated by mechanical drilling and poured with underwater concrete. The concrete pouring on the pile top should exceed the design elevation by more than 1 m, and then be carefully chiseled off to expose a clean and dense concrete surface. The concrete strength grade is C35 (underwater concrete).

[0033] The steel cage 202 is connected by sleeves. The number of steel bar joints in the same section does not exceed 1 / 2 of the total number, and the joint spacing is greater than 600mm. The mechanical connection joint grade is Class I. A group of positioning steel bars is set every 2m, and each group of 4 steel bars is evenly arranged around the reinforcing hoop. After the bored pile foundation is formed and cleaned, the thickness of the sediment at the bottom of the hole is not more than 50mm.

[0034] The anti-floating anchor rod 3 includes a second waterproof coiled material layer 301, a waterproof sleeve 302, a waterproof paste 303, a sealing strip 304, an anchor rod reinforcement 305, a positioning rib 306, a bending portion 307 and an anchor body 308. The anchor body 308 is a concrete structure. The lower section of the anchor rod reinforcement 305 is located in the anchor body 308. The top of the anchor rod reinforcement 305 extends into the foundation layer of the bottom plate 1. The positioning rib 306 is arranged on the outer side of the circumference of the lower section of the anchor rod reinforcement 305 to facilitate the centering of the reinforcement in the anchor hole. The anchor rod adopts positioning brackets or positioning hoops and other measures to ensure the position of the anchor rod in the anchor hole. A grouting conduit is arranged in the bracket. The length requirement can meet the grouting length from the bottom of the hole upward in sequence. The anchor rod reinforcement anti-corrosion layer covers the entire length of the anchor rod and penetrates into the bottom plate anchor rod from the top of the anchor rod.

[0035] The anchor bar 305 is 3φ25HRB400E grade hot-rolled threaded steel bar, with a minimum rock penetration length of 6.5m. The positioning steel pipe adopts a welded pipe with a diameter of 40mm and a length of 100mm. The main bars are spot welded into bundles at a spacing of 1500mm. The positioning steel bars (diameter 6mm) are spot welded with the anchor bar steel bars at a spacing of 1500mm to keep the anchor body parallel and ensure that the anchor is in the center of the anchor hole. The grouting pipe is 20mm, and the length is required to meet the grouting length from the bottom of the hole to the top. It is tied together with the anchor body, and a cut is made at the bottom of about 0.5m to facilitate the outflow of slurry. The grouting pipe should be lowered to the bottom of the hole together with the rod body, and the grouting pipe port should be kept 100mm from the bottom of the hole. After the drilling is completed and the hole is cleaned, the prepared steel bars and grouting pipes are lowered into the hole to the designed depth with an error of no more than 10cm. The grouting pipe port is 20 to 30cm away from the bottom of the hole.

[0036] The second waterproof membrane layer 301 is located at the anchor hole, and a waterproof cover 302 is provided on the upper layer of the second waterproof membrane layer 301. The waterproof cover 302 is filled with waterproof paste 303. The anchor rod steel bars 305 pass through the second waterproof membrane layer 301 and are located inside the waterproof cover 302. The waterproof paste 303 wraps the anchor rod steel bars 305. The anchor rod steel bars 305 are provided with a sealing strip 304 located above the waterproof cover 302.

[0037] Specifically, a waterproof rubber ring is provided on the second waterproof membrane layer, and the anti-floating anchor rod passes through the ring hole, and the gap is filled and sealed with asphalt waterproof paste. A water-expandable sealing strip with the same hole diameter as the anchor rod is provided on each single anchor rod of the base plate.

[0038] The anchor rod reinforcement 305 is welded to the reinforcement cage 202 through the bending portion 307 at the top. At the same time, the anchor rod reinforcement 305 is also connected to the foundation reinforcement through the bending portion 307 at the top. The connection between the anchor rod and the reinforcement in the foundation layer is welded to ensure that the rod body is firmly and tightly connected to the foundation layer and the pull-out pile.

[0039] The workflow of this application:

[0040] First, the anti-pullout pile is constructed, and then the anchor rod is constructed after the pile is formed. When constructing the anti-pullout pile, the mud wall is used to form the hole. The casing should be buried before drilling. The top surface of the casing should be 2m higher than the construction water level or groundwater level, and should be 0.3m higher than the construction ground. When drilling, the water level in the hole should be more than 0.5m higher than the bottom of the casing or 1.5-2m above the groundwater level. After the drilling of the anti-pullout pile is completed, the hole should be cleaned in time, the hole should be checked, the steel cage should be hoisted and the guide tube should be lowered. After the second hole cleaning, underwater concrete is poured, and the concrete strength grade is C35. The steel cage is connected by a sleeve, and the joint spacing is greater than 600mm. The mechanical connection joint grade is Class I. A group of positioning steel bars is set every 2m, and each group of 4 steel bars is evenly arranged around the reinforcing hoop. The concrete pouring on the top of the pile should exceed the design elevation by more than 1m, and then it should be carefully chiseled off to expose the clean and dense concrete surface.

[0041] When constructing anti-floating anchors, the drilling rig should be placed in place according to the designed angle, and the anchor hole drilling depth should not be less than the designed length. Every 4 anti-floating anchors form a mesh structure, the vertical inclination angle of the drilling hole is 10°, and the horizontal plane is set at 90°. After the anti-floating anchor drilling is completed, the hole should be cleaned in time, and the prepared rod body should be lowered into the hole. It is required to be lowered to the designed depth with an error of no more than 100mm. The anchor body is 3φ25HRB400E grade hot-rolled threaded steel bar, with a rock entry length of 6.5m. The positioning steel pipe uses a welded pipe with a diameter of 40mm and a length of 100mm to spot weld the main reinforcement into a bundle at a spacing of 1500mm. The positioning steel bar (diameter 6mm) is spot welded to the anchor steel bar with a spacing of 1500mm to keep the anchor body parallel and ensure that the anchor is in the center of the anchor hole. The grouting pipe is 20mm, and the length is required to meet the grouting length from the bottom of the hole to the top. It is tied together with the anchor body, and a hole is cut at the bottom about 0.5m to facilitate the outflow of slurry. The grouting pipe should be lowered to the bottom of the hole together with the rod body, and the port of the grouting pipe should be kept 100mm from the bottom of the hole. The anchor rod body is placed manually. The steel bars should be degreased and rusted, and the surface of the anchor rod stress steel bars should be treated with zinc-based coating liquid for anti-corrosion. Pipe pulling: The drilling rig is used to pull the pipe. When pulling the pipe, it should be ensured that the steel bars are not pulled out with the pipe, and the remaining length of the steel bars should be checked at any time. Pressure grouting: The grouting material is M30 pure cement slurry, the water-cement ratio is 0.4~0.60 pure cement slurry, the grouting pressure is 0.5~1MPa, and the grouting pipe should be inserted 50cm from the bottom of the hole. When grouting, when thick slurry emerges from the hole mouth, the grouting should be suspended, and the slurry should be re-pressed before the initial setting. When the thick slurry emerges again, the grouting should be stopped. In order to ensure the construction quality, the anchor top filling grouting should be over-cast by 300mm, and this over-cast part should be chiseled off when the foundation layer is constructed. Pull-out test: Pull-out test should be carried out 28 days after pressure grouting is completed. Waterproofing: Clean the anchor pile head and carry out waterproofing of anti-floating anchor rods together with waterproofing of the building foundation layer.

[0042] After the curing period is over and the test is passed, the steel bars of the anchor body are bent vertically (90 degrees) in each 120-degree direction with a portable bending machine and connected to the top steel bars of the pull-out pile. After the above work is completed, the foundation layer construction can be carried out.

[0043] The aforementioned basic examples and their further selected examples can be freely combined to form multiple embodiments, all of which are embodiments that can be adopted and claimed for protection in this application. In the scheme of this application, each selected example can be arbitrarily combined with any other basic examples and selected examples.

[0044] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A combined anti-floating construction structure, comprising a base plate (1), anti-pulling piles (2) and anti-floating anchor rods (3), characterized in that: The top of the pull-out pile (2) and the top of the anti-floating anchor rod (3) are both fixedly connected to the base plate (1), a plurality of anti-floating anchor rods (3) are arranged on the circumferential outer side of the pull-out pile (2), and the steel cage (202) of the pull-out pile (2) and the anchor rod steel bars (305) of the anti-floating anchor rod (3) are connected as a whole inside the base plate (1).

2. The combined anti-floating construction structure according to claim 1 is characterized in that: The anti-pullout piles (2) are arranged vertically, and the anti-floating anchor rods (3) are arranged obliquely.

3. The combined anti-floating construction structure according to claim 2 is characterized in that: The inclination angle of the anti-floating anchor rod (3) relative to the vertical line is 5° to 15°.

4. The combined anti-floating construction structure according to claim 2 or 3, characterized in that: The anti-floating anchor rods (3) are evenly arranged on the circumferential outer side of the pull-out pile (2), the projection of the anti-floating anchor rods (3) on the horizontal plane is the radial direction of the pull-out pile (2), and the angle between two adjacent anti-floating anchor rods (3) on the horizontal plane projection is the same.

5. The combined anti-floating construction structure according to claim 4 is characterized in that: The included angle between the two adjacent anti-floating anchor rods (3) is 120° or 90° when projected on the horizontal plane.

6. The combined anti-floating construction structure according to claim 1 is characterized in that: The base plate (1) comprises a cushion layer (101), a first waterproof coiled material layer (102), a waterproof protective layer (103) and a base layer (104) which are arranged layer by layer from bottom to top.

7. The combined anti-floating construction structure according to claim 1 or 6, characterized in that: The anti-pulling pile (2) comprises a pile body (201) and a steel cage (202) inside the pile body (201), and the top end of the steel cage (202) extends into the bottom plate (1).

8. The combined anti-floating construction structure according to claim 1 is characterized in that: The anti-floating anchor rod (3) comprises an anchor body (308) and anchor rod reinforcement (305) in the anchor body (308), the top end of the anchor rod reinforcement (305) extends into the bottom plate (1), and a positioning rib (306) is arranged on the circumferential outer side of the lower section of the anchor rod reinforcement (305).

9. The combined anti-floating construction structure according to claim 1 or 8, characterized in that: The anti-floating anchor rod (3) comprises a second waterproof coiled material layer (301), a waterproof sleeve (302), a waterproof paste (303), a sealing strip (304) and an anchor rod reinforcement (305). The second waterproof coiled material layer (301) is located at the anchor hole mouth. The upper layer of the second waterproof coiled material layer (301) is provided with a waterproof sleeve (302). The waterproof sleeve (302) is filled with a waterproof paste (303). The anchor rod reinforcement (305) passes through the second waterproof coiled material layer (301) and is located inside the waterproof sleeve (302). The waterproof paste (303) is wrapped around the anchor rod reinforcement (305). The anchor rod reinforcement (305) is provided with a sealing strip (304) located above the waterproof sleeve (302).

10. The combined anti-floating construction structure according to claim 1 or 8, characterized in that: The anchor rod reinforcement (305) is welded to the reinforcement cage (202) via the bent portion (307) at the top.

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