Soft underlying layer reinforcing structure and construction method thereof
By setting a deep pit structure and horizontal holes on the side walls of the weak sub-surface layer and performing horizontal grouting, the problems of high cost and difficult to control when dealing with weak sub-surface layer in the prior art are solved, and the effect of effectively improving the foundation bearing capacity is achieved.
Patent Information
- Application Number
- CN202411925310.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-25
- Publication Date
- 2025-02-28
AI Technical Summary
The prior art uses a high cost to use the replacement method when dealing with weak sub-lying layers, while vertical pressure grouting or other pile-type methods will disturb the upper soil layer and the effect will be difficult to control.
By setting a deep pit structure on one side of the weak sub-lying layer to be reinforced and horizontal holes are drilled on the side wall of the deep pit structure, grouting the horizontal holes is used to improve the soil mechanical properties of the weak sub-lying layer.
This method can effectively improve the soil mechanical properties of the weak sub-siding layer, meet the requirements of foundation bearing capacity, and avoid disturbances and high costs to the upper soil layer.
Smart Images
Figure CN119531343A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of building engineering construction, and in particular to a weak underlying layer reinforcement structure and a construction method thereof. Background Art
[0002] In the construction of building projects, it is often discovered after excavation that there is a weak underlying layer in part of the base, and its bearing capacity does not meet the design requirements.
[0003] There are two common ways to deal with this situation:
[0004] The first method is replacement filling, that is, to excavate the soil layer that meets the requirements on the upper part of the base and the weak underlying layer underneath, and then backfill with materials with high bearing capacity; the second method is to use vertical pressure grouting or other pile types to eliminate the influence of the weak underlying layer.
[0005] The applicant has found that the prior art has at least the following technical problems:
[0006] For method 1, if the area of the underlying layer is large, the cost will be high; for method 2, the upper soil layer that meets the requirements will be disturbed, and the treatment effect on the weak underlying layer is also difficult to control.
[0007] Therefore, there is an urgent need for a weak underlying layer reinforcement structure and a construction method thereof to solve the above technical problems. Summary of the invention
[0008] The purpose of the present invention is to provide a reinforcement structure for a weak underlying layer and a construction method thereof, so as to solve the technical problems that the replacement filling method in the prior art is expensive if the area of the underlying layer is large, and the use of vertical pressure grouting or other pile types to eliminate the influence of the weak underlying layer will disturb the upper soil layer that meets the requirements, and the treatment effect on the weak underlying layer is also difficult to control. The many technical effects that can be produced by the preferred technical solution among the many technical solutions provided by the present invention are described in detail below.
[0009] To achieve the above object, the present invention provides the following technical solutions:
[0010] The present invention provides a weak underlying layer reinforcement structure, comprising:
[0011] A deep pit structure is arranged on one side of the weak underlying layer to be reinforced, and the depth of the pit bottom of the deep pit structure is lower than the bottom surface of the weak underlying layer;
[0012] A horizontal hole is drilled along the side wall of the deep pit structure toward the weak underlying layer, and a grouting pipe is arranged in the horizontal hole for grouting the horizontal hole through the grouting pipe;
[0013] Backfill material is used to backfill the deep pit structure.
[0014] Preferably, the horizontal holes are arranged in a plurality of rows along the vertical direction, and a plurality of the horizontal holes are arranged in each row.
[0015] Preferably, two adjacent rows of horizontal holes are staggered in the vertical direction.
[0016] Preferably, the side wall of the deep pit structure close to the weak underlying layer is inclined, and the cross section gradually decreases from the top of the deep pit structure to the bottom of the pit.
[0017] Preferably, the area size of the maximum cross section of the deep pit structure does not exceed 30 square meters.
[0018] A construction method for the above-mentioned weak underlying layer reinforcement structure comprises the following steps:
[0019] S1: Determine the location of the deep pit structure;
[0020] S2: excavating the deep pit structure, the depth of which fully exposes the weak underlying layer;
[0021] S3: marking the positions of the horizontal holes on the side wall of the deep pit structure and drilling the horizontal holes;
[0022] S4: placing a grouting device in the deep pit structure, arranging a grouting pipe in the horizontal hole, and grouting the horizontal hole;
[0023] S5: withdraw the grouting equipment and backfill the deep pit structure.
[0024] Preferably, placing grouting equipment in the deep pit structure, arranging grouting pipes in the horizontal holes, and grouting the horizontal holes comprises: grouting gradually upwards from the bottom row of horizontal holes.
[0025] Preferably, the step of placing a grouting device in the deep pit structure, arranging a grouting pipe in the horizontal hole, and grouting the horizontal hole further comprises:
[0026] If the upper soil layer of the weak underlying layer is thin, grouting shall be carried out in the upper row of horizontal holes of the weak underlying layer at a grouting pressure not greater than that of the lowest row of horizontal holes;
[0027] After the reinforcement strength increases, grouting is gradually injected upwards from the bottom row of horizontal holes.
[0028] Preferably, determining the location of the deep pit structure includes:
[0029] The location of the deep pit structure to be excavated is determined based on the plane range of the weak underlying layer and the horizontal length of the horizontal grouting.
[0030] The weak underlying layer reinforcement structure provided by the present invention is achieved by arranging a deep pit structure on one side of the weak underlying layer to be reinforced, and drilling horizontal holes in the weak underlying layer through the side walls of the deep pit structure, thereby horizontally grouting the weak underlying layer to improve the soil mechanical properties of the weak underlying layer, thereby meeting the bearing capacity requirements of the foundation.
[0031] The construction method of the weak underlying layer reinforcement structure provided by the present invention is particularly suitable for the case where there is a local deep pit in the area to be treated. If there is no local deep pit, a local deep pit can be excavated as needed. The depth of the deep pit structure should be able to fully expose the weak underlying layer, and then a horizontal grouting device is arranged in the local deep pit to perform horizontal grouting operations to improve the soil mechanical properties of the weak underlying layer, thereby meeting the requirements of the foundation bearing capacity. After the grouting is completed, the unnecessary local deep pit is backfilled with materials with high bearing capacity. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0033] Figure 1 It is a structural schematic diagram of an embodiment of a weak underlying layer reinforcement structure of the present invention;
[0034] Figure 2 is a cross-sectional view of the weak underlying layer reinforcement structure of the present invention;
[0035] Figure 3 It is a flow chart of the construction method of the weak underlying layer reinforcement structure of the present invention.
[0036] In the figure: 10, deep pit structure; 101, pit bottom; 102, pit top; 20, horizontal hole; 30, weak underlying layer; 301, bottom surface; 40, foundation bottom; 50, temporary local deep pit bottom. DETAILED DESCRIPTION
[0037] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.
[0038] Figure 1 2 is a schematic diagram of the main structure of this embodiment. Figure 2 is a cross-sectional view of this embodiment, such as Figure 1 and Figure 2 As shown, the present invention provides a weak underlying layer reinforcement structure, including a deep pit structure 10, a horizontal hole 20 and backfill materials.
[0039] The deep pit structure 10 is arranged on one side of the weak underlying layer 30 to be reinforced. During construction, the plane range of the weak underlying layer 30 needs to be determined first, and the position of the temporary local deep pit structure 10 to be excavated is determined according to the plane range and the horizontal length of the horizontal grouting, so as to set the horizontal hole 20 from one side of the deep pit structure 10 and grout the horizontal hole 20.
[0040] Specifically, in this embodiment, the horizontal hole 20 is drilled along the side wall of the deep pit structure 10 toward the weak underlying layer 30, and a grouting pipe is arranged in the horizontal hole 20, and grouting is injected into the horizontal hole 20 through the grouting pipe;
[0041] Furthermore, the depth of the pit bottom 101 of the deep pit structure 10 is lower than the bottom surface 301 of the weak underlying layer 30, so as to fully expose the weak underlying layer 30. After the grouting is completed, the deep pit structure 10 is backfilled with backfill materials to complete the construction work.
[0042] This weak underlying layer reinforcement structure is achieved by setting a deep pit structure 10 on one side of the weak underlying layer 30 to be reinforced, and drilling horizontal holes 20 in the weak underlying layer 30 through the side wall of the deep pit structure 10, thereby horizontally grouting the weak underlying layer 30 to improve the soil mechanical properties of the weak underlying layer 30, thereby meeting the bearing capacity requirements of the foundation.
[0043] As an optional embodiment, the horizontal holes 20 are arranged in multiple rows along the vertical direction, and each row is provided with multiple horizontal holes 20. In this embodiment, preferably, two adjacent rows of horizontal holes 20 are arranged staggered in the vertical direction. In this arrangement, grouting can be repeated multiple times as needed until the requirements are met, and the reinforcement effect of the weak underlying layer 30 can be ensured.
[0044] As an optional embodiment, the side wall of the deep pit structure 10 close to the weak underlying layer 30 is inclined, and the cross section gradually decreases from the pit top 102 to the pit bottom 101 of the deep pit structure 10.
[0045] By setting the deep pit structure 10 as a conical structure, on the one hand, it is easy to excavate; on the other hand, the structural strength of the side wall close to the weak underlying layer 30 can be ensured to facilitate subsequent construction operations. During construction, only the weak underlying layer is reinforced, but the soil layer that meets the requirements is basically not disturbed.
[0046] As an optional embodiment, the area size of the maximum cross section of the deep pit structure 10 does not exceed 30 square meters.
[0047] During grouting construction, the grouting equipment is placed in the deep pit structure 10, and the maximum cross-sectional area of the deep pit structure 10 is set not to exceed 30 square meters. While ensuring that all the soft underlying layers 30 are exposed, it is necessary to ensure that the grouting equipment has sufficient operating space.
[0048] like Figure 3 As shown, this embodiment also provides a construction method for the above-mentioned weak underlying layer reinforcement structure, comprising the following steps:
[0049] S1: Determine the location of the deep pit structure;
[0050] Specifically, the planar range of the weak underlying layer 30 is first determined, and the location of the temporary local deep pit structure 10 to be excavated is determined based on the planar range and the horizontal length of the horizontal grouting.
[0051] S2: excavating a deep pit structure 10, the depth of the deep pit structure 10 completely exposes the weak underlying layer 30;
[0052] In this embodiment, a temporary local deep pit is excavated, and the plane size of each temporary local deep pit should not exceed 30m 2 The depth is based on completely exposing the weak underlying layer, while taking into account the operating space of the equipment.
[0053] S3: marking the positions of the horizontal holes on the side wall of the deep pit structure 10 and drilling the horizontal holes;
[0054] Specifically, during construction, the points for horizontal grouting are marked on the side walls of the weak underlying layer 30 exposed by the deep pit structure 10, and then horizontal holes are drilled.
[0055] S4: placing grouting equipment in the deep pit structure 10, arranging grouting pipes in the horizontal holes, and grouting the horizontal holes; including: horizontal grouting in the weak underlying layer according to the grouting sequence until all grouting is completed.
[0056] The grouting sequence generally starts with the bottom row of horizontal holes 20, and then gradually moves upward until all grouting is completed.
[0057] It should be noted that if the soil layer that meets the requirements above the weak underlying layer 30 is relatively thin, grouting should be performed in the upper row of horizontal holes 20 of the weak underlying layer 30 at a grouting pressure not greater than that of the lowest row of horizontal holes 20; and after the reinforcement strength increases, grouting should be gradually performed upwards from the lowest row of horizontal holes 20.
[0058] S5: Remove the grouting equipment and backfill the deep pit structure 10 with materials that meet the requirements.
[0059] This construction method of the weak underlying layer reinforcement structure is particularly suitable for the situation where there is a local deep pit in the area to be treated. If there is no local deep pit, a local deep pit can be excavated as needed. The depth of the deep pit structure 10 should be able to fully expose the weak underlying layer, and then a horizontal grouting device is arranged in the local deep pit to perform horizontal grouting operations to improve the soil mechanical properties of the weak underlying layer 30, so as to meet the requirements of the foundation bearing capacity. After the grouting is completed, the unnecessary local deep pit is backfilled with materials with high bearing capacity.
[0060] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.
Claims
1. A weak underlying layer reinforcement structure, characterized in that: include: A deep pit structure is arranged on one side of the weak underlying layer to be reinforced, and the depth of the pit bottom of the deep pit structure is lower than the bottom surface of the weak underlying layer; A horizontal hole is drilled along the side wall of the deep pit structure toward the weak underlying layer, and a grouting pipe is arranged in the horizontal hole for grouting the horizontal hole through the grouting pipe; Backfill material is used to backfill the deep pit structure.
2. The weak underlying layer reinforcement structure according to claim 1 is characterized in that: The horizontal holes are arranged in a plurality of rows along the vertical direction, and each row is provided with a plurality of the horizontal holes.
3. The weak underlying layer reinforcement structure according to claim 2 is characterized in that: Two adjacent rows of horizontal holes are arranged alternately in the vertical direction.
4. The weak underlying layer reinforcement structure according to any one of claims 1 to 3, characterized in that: The side wall of the deep pit structure close to the weak underlying layer is inclined, and the cross section gradually decreases from the top of the deep pit structure to the bottom of the pit.
5. The weak underlying layer reinforcement structure according to any one of claims 1 to 3, characterized in that: The maximum cross-sectional area of the deep pit structure does not exceed 30 square meters.
6. A construction method for a weak underlying layer reinforcement structure according to any one of claims 1 to 5, characterized in that: The steps include: S1: Determine the location of the deep pit structure; S2: excavating the deep pit structure, the depth of which fully exposes the weak underlying layer; S3: marking the positions of the horizontal holes on the side wall of the deep pit structure and drilling the horizontal holes; S4: placing a grouting device in the deep pit structure, arranging a grouting pipe in the horizontal hole, and grouting the horizontal hole; S5: withdraw the grouting equipment and backfill the deep pit structure.
7. The construction method of the weak underlying layer reinforcement structure according to claim 6 is characterized by: The step of placing grouting equipment in the deep pit structure, arranging grouting pipes in the horizontal holes, and grouting the horizontal holes comprises: grouting gradually upwards from the bottom row of horizontal holes.
8. The construction method of the weak underlying layer reinforcement structure according to claim 7 is characterized in that: The step of placing a grouting device in the deep pit structure, arranging a grouting pipe in the horizontal hole, and grouting the horizontal hole also includes: If the upper soil layer of the weak underlying layer is thin, grouting shall be carried out in the upper row of horizontal holes of the weak underlying layer at a grouting pressure not greater than that of the lowest row of horizontal holes; After the reinforcement strength increases, grouting is gradually injected upwards from the bottom row of horizontal holes.
9. The construction method of the weak underlying layer reinforcement structure according to claim 6 is characterized in that: Determining the location of the deep pit structure includes: The location of the deep pit structure to be excavated is determined based on the plane range of the weak underlying layer and the horizontal length of the horizontal grouting.