Underground structure shallow excavation anti-floating remediation structure
By arranging precast slab structures and cross beams above the basement roof slab, the problems of high investment and complex construction in existing basement anti-buoyancy design are solved, achieving a fast and economical anti-buoyancy effect, which is applicable to existing or newly built basements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGJIANG SURVEY PLANNING DESIGN & RES CO LTD
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-21
AI Technical Summary
Existing anti-buoyancy design methods for basements involve high investment, complex construction, and high risks, especially during urban renewal processes when rising groundwater levels lead to frequent problems.
The precast slab structure is adopted. The precast slab structure is arranged by shallow excavation above the basement roof slab. One end of the precast slab is supported at the junction of the basement side wall and the roof slab, and the other end is supported in the soil. Combined with the cross beam belt and the cantilever structure of the bottom slab, additional buoyancy resistance is provided.
Provides additional buoyancy resistance, reduces construction complexity and investment, shortens construction time, maintains waterproof integrity, reduces impact on the surrounding environment, and is suitable for existing or new basements.
Smart Images
Figure CN224531762U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of underground engineering technology, specifically to a shallow excavation anti-buoyancy remedial structure for underground structures. Background Technology
[0002] The development of underground space in urban core areas can efficiently utilize limited land resources and achieve intensive development of three-dimensional space. One of the key challenges in the design of basements within underground structures is anti-buoyancy design. In recent years, due to the gradual improvement of urban renewal, the rising groundwater level has led to a surge in basement problems such as cracking and shear failure. Therefore, anti-buoyancy remediation of basements is of practical significance in addressing this situation.
[0003] Currently, there are two main approaches to anti-buoyancy design for basements: 1. Install anti-buoyancy anchors inside the basement to achieve anti-buoyancy remediation; 2. During use, continuously dewater the basement to control the anti-buoyancy water level and achieve anti-buoyancy remediation.
[0004] The above anti-buoyancy methods require the use of basement space or the addition of dewatering equipment, resulting in higher investment, more complex construction, and a tighter construction area. They also increase the risk to nearby buildings and structures. Utility Model Content
[0005] The purpose of this utility model is to provide a shallow excavation anti-buoyancy remedial structure for underground structures, which can solve the technical problems of high investment, complex construction and high risk of existing basement anti-buoyancy methods.
[0006] To achieve the above objectives, this utility model provides the following technical solution: This utility model discloses a shallow excavation anti-buoyancy remedial structure for underground structures, including a basement and an anti-buoyancy structure. The basement is located inside the underground structure, and the anti-buoyancy structure is connected to the basement. The basement has a hollow cavity structure, and its exterior includes a top slab, side walls, and a bottom slab. The two ends of the side walls are connected to the top slab and the bottom slab, respectively. The anti-buoyancy structure includes a precast slab structure, which is arranged above the top slab. One end of the precast slab structure is supported at the junction of the basement side wall and the top slab, and the other end is supported in the soil of the underground structure.
[0007] As a preferred embodiment, the precast slab structure includes a precast slab body and a crossbeam band, wherein the crossbeam band is arranged at the upper and lower ends of the precast slab body and / or inside the precast slab body. The additional crossbeam band ensures the safety and stability of the force transmission system.
[0008] Furthermore, the cross beam band includes at least one horizontal beam and one vertical beam, the horizontal beam being arranged along the width direction of the precast slab body and the vertical beam being arranged along the length direction of the precast slab body.
[0009] Furthermore, the precast slab structure is arranged continuously or intermittently along the outer contour of the basement.
[0010] As a preferred embodiment, the anti-buoyancy structure further includes a cantilevered bottom slab structure, which is an outward extension of the basement bottom slab. The extension is integrally connected with the bottom slab and the side walls, and the thickness of the extension is greater than the thickness of the bottom slab and the side walls, respectively.
[0011] As a preferred embodiment, the basement also includes a roof slab haunch, which is located at the junction of the basement roof slab and the side walls. This can reduce local stress concentration at abrupt changes in cross-section.
[0012] The beneficial effects of this utility model are: This utility model provides a shallow excavation anti-buoyancy remedial structure for underground structures, which can solve the technical problems of high investment, complex construction and high risk of existing basement anti-buoyancy methods.
[0013] The precast slab structure used in the described technical solution provides additional buoyancy resistance to the basement, ensuring the buoyancy stability of existing or newly built basements. Only shallow excavation on the top slab is required to provide significant buoyancy resistance to existing basements, minimizing repeated excavation, reducing environmental impact, significantly shortening the construction period, and promoting energy conservation and environmental protection. This invention can also be used for newly built basements, suitable for projects with limited space for adjacent underground structures. The precast slab structure can be prefabricated in sections without the need for on-site pouring; it can be directly placed on the top slab after being transported to the site, enabling rapid construction. The precast slab structure only needs to be placed on the top slab without connection to it, thus preserving the waterproof integrity of the basement structure.
[0014] Enhanced buoyancy resistance: The precast slab structure and the soil cover above it increase the weight and provide additional buoyancy resistance.
[0015] Simplified construction: Precast slabs can be prefabricated in the factory and directly placed and installed on site, without the need for on-site pouring or complex anchoring.
[0016] Waterproof integrity is maintained: the precast slab rests only on the top slab and is not connected to the top slab to avoid damaging the waterproof layer.
[0017] Reduce repeated excavation: Only one shallow excavation is needed, reducing earthwork and disturbance.
[0018] Minimal impact on the surrounding environment: shallow excavation depth reduces noise, vibration, and damage.
[0019] Shorten construction period: Precast slabs can be manufactured in the factory and installed quickly on site.
[0020] Energy conservation and environmental protection: reducing resource consumption and emissions.
[0021] Wide applicability: Suitable for existing or newly built basements, especially for projects with limited space.
[0022] This invention is of great significance in researching a shallow excavation anti-buoyancy remedial measure and its construction method. It provides anti-buoyancy force by placing a precast slab on top of the shallow excavation and then backfilling with soil. It has the advantage of simple construction and can be extended to various complex existing or newly built underground projects. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of Embodiment 1 of the present utility model.
[0024] Figure 2 This is a structural schematic diagram of Embodiment 2 of the present invention.
[0025] Figure 3 for Figure 2 Structural diagram of the basement and the cantilevered structure of the foundation slab.
[0026] Figure 4 This is a structural schematic diagram of Example 1 of the crossbeam belt.
[0027] Figure 5 This is a schematic diagram of the structure of Embodiment 2 of the crossbeam belt.
[0028] Figure 6 This is a structural schematic diagram of Example 3 of the crossbeam belt.
[0029] Figure 7 This is a schematic diagram of the structure of Example 4 of the crossbeam belt.
[0030] In the picture: 0 Ground line; 1 Underground structure; 2 Underground retaining piles; 3 Basement; 3 Side wall; 3-1 Top slab haunch; 3-2 Bottom slab cantilever structure; 3-4 Top slab; 3-5 Bottom slab; 4 Precast slab body; 4-1 Slope excavation line; 4-2 Cross beam band; Anti-buoyancy structure: precast slab structure (precast slab body, cross beam belt), and cantilevered bottom slab structure. Detailed Implementation
[0031] To make the technical problem solved by this utility model, the technical solution adopted, and the technical effect achieved clearer, the technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the accompanying drawings, not all of them.
[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Specifically, the terms "first position" and "second position" refer to two different positions.
[0033] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0034] This utility model aims to propose a shallow excavation anti-buoyancy remedial structure for underground structures, which is used to solve the technical problem of anti-buoyancy remediation for underground structures, and provides a construction method for a precast slab structure to realize this anti-buoyancy remediation.
[0035] This utility model relates to a shallow excavation anti-buoyancy remedial structure for underground structures. The precast slab structure is located above the basement roof slab, with part of it supported at the junction of the basement sidewalls and the roof slab, and part of it supported in the soil. The soil cover weight above the precast slab structure can provide anti-buoyancy force for the basement; half of this weight can be taken as the additional anti-buoyancy force in the calculation. This utility model can be used to remediate the anti-buoyancy of existing underground structures. Simply shallow excavation to above the roof slab and embedding the precast slab structure can increase the soil cover weight of the basement and provide anti-buoyancy force. This utility model can also be used to remediate the anti-buoyancy of newly built underground structures, replacing the cantilevered base slab to provide anti-buoyancy force.
[0036] This utility model provides a shallow excavation anti-buoyancy remedial structure for underground structures, including a basement 3 and an anti-buoyancy structure. The basement 3 is located inside the underground structure, and the anti-buoyancy structure is connected to the basement 3.
[0037] The basement 3 has a hollow internal structure, and its outer perimeter includes a top slab 3-4, side walls 3-1, a bottom slab 3-5, and a top slab axle 3-2. The two ends of the side walls 3-1 are connected to the top slab 3-4 and the bottom slab 3-5, respectively. The top slab axle 3-2 is located at the junction of the basement's top slab 3-4 and side walls 3-1. The top slab axle 3-2 can reduce local stress concentration at the abrupt change in cross-section. The top slab axle 3-2 is located at the junction of the basement's top slab and side walls to reduce local stress concentration at the abrupt change in cross-section.
[0038] The anti-buoyancy structure includes a precast slab structure, which is arranged above the top slab 3-4. One end of the precast slab structure is supported at the junction of the basement side wall 3-1 and the top slab 3-4, and the other end is supported in the soil of the underground structure. The precast slab structure includes a precast slab body 4 and a cross beam band 4-2, which is arranged at the upper end, lower end, and / or inside the precast slab body 4. The cross beam band 4-2 includes at least one horizontal beam and one vertical beam. The horizontal beam is arranged along the width direction of the precast slab body 4, and the vertical beam is arranged along the length direction of the precast slab body 4. The additional cross beam band 4-2 can ensure the safety and stability of the force transmission system. The precast slab structure is arranged continuously or intermittently along the outer contour of the basement 3.
[0039] The precast slab structure is arranged continuously along the outer contour of the basement, or it can be arranged intermittently and flexibly according to the actual situation of the underground space. The precast slab structure uses C30 concrete with a P6 waterproof rating, prefabricated in a factory. It can be set in 3-5 meter sections depending on the size of the basement and transportation convenience. After transportation to the site, shallow excavation is carried out for placement, resulting in a fast construction cycle and minimal impact on the surrounding environment. The thickness of the precast slab structure is 300mm, and cross beams can be added based on stress calculations to ensure the safety and stability of the force transmission system. During the lowering of the precast slab structure, the waterproofing system of the basement roof slab and side walls should not be damaged.
[0040] The anti-buoyancy structure also includes a bottom plate cantilever structure 3-3, which is an outward extension of the basement bottom plate 3-5. The extension is integrally connected with the bottom plate 3-5 and the side wall 3-1, and the thickness of the extension is greater than the thickness of the bottom plate 3-5 and the side wall 3-1, respectively.
[0041] The present invention will be further described below with reference to specific embodiments in conjunction with the accompanying drawings. These examples do not constitute a limitation of the present invention and are not intended to restrict the scope of protection of the present invention. All equivalent modifications made in accordance with the requirements of the present invention are within the scope of protection of the present invention.
[0042] Example 1: like Figure 1As shown in the schematic diagram of the anti-buoyancy remedial structure of Embodiment 1 of this utility model, an anti-buoyancy remedial structure for shallow excavation of underground structures includes an underground structure 1; underground retaining piles 2; a basement 3; side walls 3-1; a top slab armhole 3-2; a precast slab body 4; and a slope excavation line 4-1. The basement 3 is located below the ground line 0. The basement 3 includes a top slab 3-4, side walls 3-1, a bottom slab 3-5, and a top slab armhole 3-2. The two ends of the side walls 3-1 are connected to the top slab 3-4 and the bottom slab 3-5, respectively. A shallow pit is excavated above the top slab 3-4. One side is supported by the underground retaining piles 2 adjacent to the underground structure 1, and the other side is excavated along the slope excavation line 4-1 on the top slab 3-4 of the basement. The precast slab body 4 is arranged above the top slab 3-4. One end of the precast slab body 4 is supported at the junction of the basement side wall 3-1 and the top slab 3-4, and the other end is supported in the soil of the underground structure. In this embodiment, the precast slab body 4 serves as the main anti-buoyancy structure, providing significant anti-buoyancy force for the basement. The precast slab structure can be prefabricated in sections without the need for on-site casting; it can be directly placed on the roof slab after being transported to the site, allowing for quick construction. The precast slab structure only needs to be placed on the roof slab 3-4 without needing to be connected to it, thus preserving the waterproof integrity of the basement structure.
[0043] Example 2: like Figure 2 , 3 As shown in the schematic diagram of the anti-buoyancy remedial structure of Embodiment 2 of this utility model, it includes an underground structure 1; underground retaining piles 2; basement 3; side wall 3-1; top slab haunch angle 3-2; bottom slab cantilever structure 3-3; precast slab 4; and slope excavation line 4-1.
[0044] Figure 3 This is a schematic diagram of the basement and the cantilevered structure of the basement slab. Basement 3 is located below ground level 0 and includes a top slab 3-4, side walls 3-1, a base slab 3-5, and a top slab abutment 3-2. The two ends of side walls 3-1 are connected to the top slab 3-4 and the base slab 3-5, respectively. The cantilevered structure 3-3 is an outward extension of the basement base slab 3-5, integrally connected to the base slab 3-5 and side walls 3-1. The thickness of the extension is greater than the thickness of both the base slab 3-5 and the side walls 3-1. The cantilevered structure 3-3 is arranged along the outer contour of the basement 3.
[0045] A shallow pit is excavated above the top slab 3-4, with one side supported by underground retaining piles 2 adjacent to the underground structure 1, and the other side excavated along the slope excavation line 4-1 on the basement top slab 3-4. The precast slab body 4 is arranged above the top slab 3-4, with one end of the precast slab body 4 supported at the junction of the basement side wall 3-1 and the top slab 3-4, and the other end supported in the soil of the underground structure.
[0046] In this embodiment, the precast slab body 4 and the cantilevered base slab structure 3-3 together serve as an anti-buoyancy structure, providing significant anti-buoyancy force for the basement. The precast slab structure can be prefabricated in sections without the need for on-site casting; it can be directly placed on the roof slab after being transported to the site, allowing for quick construction. The precast slab structure only needs to be placed on the roof slab 3-4 without needing to be connected to it, thus preserving the waterproof integrity of the basement structure. The cantilevered base slab structure 3-3 is integrally formed with the basement; by setting a groove, it extends the outer contour of the base slab, increasing the weight of the backfill soil, thereby achieving the purpose of anti-buoyancy remediation.
[0047] Figure 4-7 The diagram shows four embodiments of the cross beam strip. The cross beam strip 4-2 is arranged at the upper end, lower end, and / or inside the precast slab body 4 to ensure the safety and stability of the force transmission system. The cross beam strip 4-2 includes at least one horizontal beam and one vertical beam. The horizontal beam is arranged along the width direction of the precast slab body 4, and the vertical beam is arranged along the length direction of the precast slab body 4.
[0048] Figure 4 This is a structural schematic diagram of Embodiment 1 of the cross beam strip. The cross beam strip is arranged at the upper or lower end of the precast slab body 4, and the cross beam strip includes two horizontal beams and two vertical beams arranged vertically.
[0049] Figure 5 This is a schematic diagram of the structure of Embodiment 2 of the cross beam strip. The cross beam strip is arranged at the upper or lower end of the precast slab body 4, and the cross beam strip includes two horizontal beams and three vertical beams arranged vertically.
[0050] Figure 6 This is a schematic diagram of the structure of Embodiment 3 of the cross beam strip. The cross beam strip is arranged inside the precast slab body 4, and the cross beam strip includes two horizontal beams and two vertical beams arranged vertically.
[0051] Figure 7 This is a schematic diagram of the structure of Embodiment 4 of the cross beam strip. The cross beam strip is arranged inside the precast slab body 4, and includes two horizontal beams and three vertical beams arranged vertically.
[0052] Taking an existing basement with an adjacent underground structure as an example, this implementation plan only requires shallow excavation to the top of the roof slab to increase buoyancy resistance. The construction method for implementing this utility model solution is as follows: First, a shallow pit is excavated above the basement roof slab 3-4. One side is supported by the underground retaining piles 2 of the adjacent underground structure 1, and the other side is excavated on a slope on the basement roof slab 3-4. When the excavation reaches 300mm above the basement roof slab 3-4, manual excavation is switched to avoid damaging the waterproofing of the roof slab 3-4.
[0053] Then, the precast concrete slab 4 is lowered. Considering that the base of the precast concrete slab 4 is backfill soil, it can be directly placed on the basement roof slab 3-4 and the backfill soil.
[0054] Finally, backfilling the surface of the precast concrete slab 4 with soil will provide additional buoyancy resistance for the basement 3.
[0055] This invention provides significant anti-buoyancy support to existing basements through shallow excavation on the top slab, minimizing repeated excavation, reducing environmental impact, significantly shortening construction time, and promoting energy conservation and environmental protection. It can also be used for new basements, particularly suitable for projects with limited space for adjacent underground structures. Employing a precast slab structure, which can be prefabricated in sections without on-site pouring, the slabs are transported to the site and directly placed on the top slab, enabling rapid construction. The precast slabs only need to be placed on the top slab without connection, thus preserving the waterproof integrity of the basement structure. This invention solves the technical problems of high investment, complex construction, and high risk associated with existing basement anti-buoyancy methods, offering the advantage of simple construction and applicability to various complex existing or new underground projects.
[0056] The parts not described in detail are all existing technologies that are generally accepted in the industry. It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims of this utility model.
Claims
1. A shallow excavation anti-buoyancy remedial structure for underground structures, characterized in that: Includes a basement (3) and an anti-buoyancy structure, wherein the basement (3) is located within the underground structure and the anti-buoyancy structure is connected to the basement (3); The basement (3) has a hollow structure inside and includes a top slab (3-4), side walls (3-1), and a bottom slab (3-5) on the outside. The two ends of the side walls (3-1) are connected to the top slab (3-4) and the bottom slab (3-5) respectively. The anti-buoyancy structure includes a precast slab structure, which is arranged above the top slab (3-4). One end of the precast slab structure is supported at the junction of the basement side wall (3-1) and the top slab (3-4), and the other end is supported in the soil of the underground structure.
2. The shallow excavation anti-buoyancy remedial structure for underground structures according to claim 1, characterized in that: The precast slab structure includes a precast slab body (4) and a cross beam belt (4-2), which is arranged at the upper end, lower end and / or inside the precast slab body (4).
3. The shallow excavation anti-buoyancy remedial structure for underground structures according to claim 2, characterized in that: The cross beam strip (4-2) includes at least one horizontal beam and one vertical beam. The horizontal beam is arranged along the width direction of the precast slab body (4), and the vertical beam is arranged along the length direction of the precast slab body (4).
4. The shallow excavation anti-buoyancy remedial structure for underground structures according to claim 3, characterized in that: The precast slab structure is arranged continuously or intermittently along the outer contour of the basement (3).
5. The anti-buoyancy remedial structure for shallow excavation of underground structures according to claim 1, characterized in that: The anti-buoyancy structure also includes a bottom plate cantilever structure (3-3), which is an outward extension of the basement bottom plate (3-5). The extension is integrally connected with the bottom plate (3-5) and the side wall (3-1), and the thickness of the extension is greater than the thickness of the bottom plate (3-5) and the side wall (3-1).
6. A shallow excavation anti-buoyancy remedial structure for underground structures according to any one of claims 1 to 5, characterized in that: The basement (3) also includes a top plate axle angle (3-2), which is located at the junction of the top plate (3-4) and the side wall (3-1) of the basement.